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Title:
AGENT FOR NUCLEATION OF POLYOLEFIN AND ELIMINATION OF FOULING IN A GAS PHASE POLYMERISATION REACTOR
Document Type and Number:
WIPO Patent Application WO/2015/021948
Kind Code:
A1
Abstract:
An agent for elimination of formation of polyolefin powder fouling on walls of gas-phase polymerization reactors and their recycles and for preparation of a nucleated polyolefin directly during polymerization of 1-olefins on Ziegler-Natta catalysts. This agent remains dispersed in the polyolefin material and it acts as a nucleator. It comprises at least one compound prepared by the reaction of an organoaluminium with a compound based on derivatives of amides of aliphatic or aromatic carboxylic acids

Inventors:
SKOUMAL MIROSLAV (CZ)
JAKUBEC TOMAS (CZ)
HOZA ADAM (CZ)
POSPISIL LADISLAV (CZ)
Application Number:
PCT/CZ2014/000087
Publication Date:
February 19, 2015
Filing Date:
August 11, 2014
Export Citation:
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Assignee:
POLYMER INST BRNO SPOL S R O (CZ)
International Classes:
C07F5/06; C08F2/44; C08F10/00
Domestic Patent References:
WO2012045288A12012-04-12
WO2009157770A12009-12-30
WO2009010413A12009-01-22
WO2004072168A22004-08-26
WO2003102069A12003-12-11
WO2012045288A12012-04-12
Foreign References:
US3489736A1970-01-13
EP0005215A21979-11-14
US5026795A1991-06-25
EP0366823A11990-05-09
EP0494316A11992-07-15
CZ281858B61997-03-12
US6111034A2000-08-29
EP1161465A12001-12-12
EP0453116A11991-10-23
EP1448610A12004-08-25
US20050203259A12005-09-15
EP2192133A12010-06-02
EP0940431A11999-09-08
EP2096137A12009-09-02
EP0962489A21999-12-08
EP0557721A21993-09-01
Attorney, Agent or Firm:
DVORAKOVA, Martina (Sedlak Smol, Mendlovo namesti 1a Brno, CZ)
Download PDF:
Claims:
Claims

1. An agent for elimination of formation of polyolefin powder fouling on walls of gas- phase polymerization reactors and their recycles and for preparation of a nucleated polyolefin directly during polymerization of 1-olefins on Ziegler-Natta catalysts characterized in that it comprises at least one compound prepared by the reaction of an organoaiuminium with a compound based on derivatives of amides of aliphatic or aromatic carboxylic acids.

2. The agent according to claim 1 , characterized in that the compound on the basis of derivatives of amides of aliphatic or aromatic carboxylic acids is selected from the group of compounds of general formula I:

wherein k can be an integer of 3 or 4;

Y1 is a residue obtained after elimination of all carboxyl groups from 1,2,3-propanetricarboxyiic acid, 1 ,2,3,4-butanetetracarboxylic acid or 1 ,3,5-benzenetricarboxylic acid,

Y2 are three or four of the same or different groups, independent of each other consisting of H or linear or branched Ci - C-|0 alkyl,

or selected from the group of compounds of general formulas II, III, !V and V:

(II), wherein I1, i2 and I3 or J1, J2 and J3 or K1, K2 and K3 or L , L2 and L3 are independently a linear or branched Ci - C2o alkyl or unsubstituted C3 - Ce cycloalkyl or substituted with 1, 2, 3, or 4 Ci - C4 alkyls,

or selected from the group of compounds of general formula VI, VII and VIM: wherein for compounds of the general formula VI R1 represents the residue after the elimination of hydroxyl groups of saturated or unsaturated aliphatic C3 - C2o dicarboxylic acids or the residue after the elimination of hydroxyl groups of saturated or unsaturated alicyclic C6 - C30 dicarboxylic acids or the residue after the elimination of hydroxyl groups of aromatic C8 - C30 dicarboxylic acids,

R2 and R3 are same or different C3 - C12 cycloalkyls unsubstituted or substituted by one or more radicals selected from the group of aliphatic Ci - C20 alkyls, branched C3 - C20 alkyls; aliphatic C2 - C20 alkenyls, branched C3 - C20 alkenyls, C3 - cycloalkyls and phenyls; or C3 - C12 cycloalkenyls unsubstituted or substituted by one or more radicals selected from the group aliphatic Ci - C20 alkyls, branched C3 - C20 alkyls; aliphatic C2 - C20 alkenyls, branched C3 - C2o alkenyls, C3 - Ci2 cycloalkyls and phenyls,

wherein for compounds of the general formula VII U1 represents the residue from saturated or unsaturated aliphatic C2 - C20 diamines, the residue from alicyclic C4 - C28 diamines, the residue from heterocyclic C - Ci diamines and the residue from aromatic C6 - C28 diamines,

U2 and U3 are same or different C3 - C12 cycloalkyls unsubstituted or substituted by one or more radicals selected from the group of aliphatic Ci - C20 alkyls, branched C3 - C2o alkyls; aliphatic C2 - C20 alkenyls, branched C3 - C2o alkenyls, C3 - C12 cycloalkyls and phenyls; or C3 - C12 cycloalkenyls unsubstituted or substituted by one or more radicals selected from the group aliphatic Ci - C20 alkyls, branched C3 - C20 alkyls; aliphatic C2 - C2o alkenyls, branched C3 - C20 alkenyls, C3 - Ci2 cycloalkyls and phenyls,

wherein for compounds of the general formula VIII V1 represents the residue from saturated or unsaturated aliphatic C2 - C2g amino carboxylic acids, the residue from saturated or unsaturated alicyclic C7 - C13 amino carboxylic acids and residue from aromatic C7 - C15 amino carboxylic acids,

V2 and V3 are same or different substituents and V2 is the same as U2 or U3 for the compounds of the general formula VII and V3 is the same as R2 and R3 for the compounds of the general formula VI.

3. The agent according to claim 1 or 2, characterized in that Y1 for the compound of the general formula I is a residue obtained after elimination of all carboxyl groups from 1 ,2,3-propanetricarboxylic acid, 1 ,2,3,4-butanetetracarboxy!ic acid or

I , 3,5-benzenetricarboxylic acid,

Y2 for the compound of the general formula I is hydrogen or methyl bounded to cyclohexyl in the position 2,

II, I2 and I3 for the compound of the general formula II or J2 and J3 for the compound of the general formula III or K1 for the compound of the general formula IV are independently isopropyl, secondary butyl, tertiary butyl, 1-methylbutyl, 1- methylpentyl, 1 -ethyl penty!, 1 ,1-dimethylpropyl, 2, 2-di methyl propyl, 1 ,1-dimethylbutyl, 1 ,1-dimethylhexyl, 1-ehylpropyl, 1-propylbutyl, 1-methylethenyl, 1-methyl-2-propenyl, 1-methyl-2-butenyl, cyclopentyl or cyclohexyl,

L1, L2 and L3 for the compound of the general formula V or K2 and K3 for the compound of the general formula IV or J3 for the compound of the general formula 111 are independently isopropyl, secondary butyl, tertiary butyl, 1 ,1-dimethylpropyl, 1 ,2-dimethylpropyl, 2,2-dimethy!propyl, tertiary octyl, cyclopentyl, cyclohexyl, 2-methylcyclohexyl, 2,3-dimethyicyclohexyl, 1-ethylcyclohexyl or -adamantyl,

R of the compound with general formula VI is the residue after removal of hydroxyl groups from 1 ,2-ethanedicarboxylic acid, 1 ,3-propanedicarboxylic acid, ,4-butanedicarboxylic acid, 1 ,5-pentanedicarboxylic acid,

1 ,6-hexanedicarboxylic acid, 1 ,7-heptanedicarboxylic acid,

1 ,8-octanedicarboxylic acid, 1 ,4-cyclohexanedicarboxylic acid, ,4-benzenedicarboxylic acid, 1 ,5-naphthalenedicarboxylic acid, biphenyl-4,4'- dicarboxy!ic acid and biphenyl-2,2'-dicarboxylic acid,

R2 and R3 for the compound of the general formula VI are cyclopentyl, cyclohexyl and phenyl unsubstituted or substituted methyl or ethyl, U1 for the compound of the general formula VII is the residue from

1.2- ethandiamine, 1 ,3-propanediamine, 1,4-butanediamine, 1 ,5-pentanediamine, 1 ,6-hexanediamine, 1 ,7-heptanediamine, 1,8-octanediamine, 1 ,4-cyclohexanediamine, 1 ,4-benzenediamine, 1,5-naphthaienediamine, biphenyl- 4,4'-diamine and biphenyl-2,2'-diamine,

U2 and U3 for the compound of the general formula VII are cyclopentyl, cyclohexyl and phenyl unsubstituted or substituted by methyl or ethyl,

V1 for the compound of the general formula VIM is the residue from 2-aminoethanoic acid, 3-aminopropanoic acid, 4-aminobutanoic acid, 5-aminopentanoic acid, 6-aminohexanoic acid, 7-aminoheptanoic acid, 8-aminooctanoic acid,

4- aminocyc!ohexanecarboxylic acid, 4-aminobenzoic acid,

5- aminonaphthalenecarboxylic acid, 4'-amino-4-biphenylcarboxylic acid and 2'-amino-2-biphenylcarboxylic acid,

V2 for the compound of the general formula VIII is the same as U2 and U3 of the compound with general formula VII,

V3 for the compound of the general formula VIII is the same as R2 and R3 for the compound with general formula VI.

4. The agent according to any of claims 1 - 3, characterized in that the compound on the basis of derivatives of amides of aliphatic or aromatic carboxylic acids is N,N',N"-tris(2-methylcyclohexyl)-1 ,2,3-propanetricarboxylic amide, Ν,Ν',Ν''-triscyclohexyM ,2,3-propanetricarboxylic amide, Ν,Ν',Ν''-triscyclohexyl- 1 ,3,5-benzenetricarboxylic amide, N)N',N",N"'-tetra(2-methy[cyclohexyl)-1 ,2,3,4- butanetetracarboxylic amide, N,N',N",N"'-tetracyclohexyl-1 ,2,3,4- butanetetracarboxylic amide, 1,3,5-tris(2,2-dimethylpropaneamino)-benzene, 1,3,5- tris(2-ethylbutaneamino)-benzene, 1 ,3,5-tris(2,2-dimethylbutaneamino)-benzene, 1-isobutaneamino-3,5-bis(pivaloylamino)-benzene, 2,2-dimethy!butaneamido-3,5- bis(pivaloylamino)-benzene, 2,2-dimethy[butaneamido-3,5-bis(pivaloylamino}- benzene, 1 ,3-bis(isobutaneamino)-5-pivaloylaminobenzene,

1.3- bis(isobutaneamino)-5-(2,2-dimethylbutane)aminobenzene, 1 ,3-bis(2,2- dimethy[butaneamino)-5-pivaloylaminobenzene, 1,3-bis(2,2-dimethylbutaneamino)- 5-isobutaneaminobenzene, 1 ,3-bis(2,2-dimethylbutaneamido)-5-(3,3- dimethylbutane)aminobenzene, 5-pivaloylamino-isophthalic acid N,N'-di-t- butandiamide, 5-pivaloylamino-isophthalic acid N,N'-di-cyclohexanediamide, N-t-buty[-3,5-bis(pivaloylamino)benzeneamide, N-cyclopentyI-3,5- bis(pivaloylamino)benzeneamide, N-cyclohexyl-3,5- bis(pivaloylamino)benzeneamide, N-isopropyl-3,5-bis(pivaloylamino)benzeneamide, N-t-butyl-3,5-bis(2,2-dimethylbutaneamino}benzeneamide, N,N'-dicyclohexyl-2,6- naphthalenedicarboxylic, Ν,Ν'-dicycIohexylterephthalamide, N,N'-dicyclohexyl-1 ,4- cyclohexanedicarboxylic, N,N'-dicyclohexyl-4,4'-biphenyldicarboxylic, N,N'-bis(p- methylphenyl)hexanediamide, N,N'-bis(p-ethylphenyl)hexanediamide, Ν,Ν'- bis(cyclohexylphenyl)hexanediamide, N,N'-1,4-phenylbiscyc]ohexanecarboxylic, N,N'-1 ,5-naphthalenebisbenzeneamide, N,N'-1 ,4-cyclohexanebisbenzeneamide and N,N'-1 ,4-cyclohexanebiscyclohexanecarboxylic,

5. The agent according to claim 4, characterized in that the compound on the basis of derivatives of amides of aliphatic or aromatic carboxylic acids is in particular N,N\N"-tris(2-methylcyclohexyl)-1 ,2,3-propanetricarboxylic amide, 1 ,3,5-tris(2,2- dimethylpropaneamino)-benzene and N,N'-dicyclohexyl-2,6- naphthaienedicarboxylic amide.

6. The agent according to claim 1 , characterized in that organoaluminium is trimethylaluminium, triethylaluminium, tripropylaluminium, triisopropylaluminium, tributylaluminium, triisobutylaiuminium, trihexylaluminium, triisohexyialuminium, trioctyl aluminium, tridecyialuminium, dimethylaluminium chloride, diethylaluminium chloride, diisobutylalumtnium chloride, methylaluminium dichloride, ethylaluminium dichloride or isobutylaluminium dichloride.

7. A method of agent preparation according to any of claims 1 to 6, characterized in that it is performed by a reaction of compounds of the genera! formulas I to VIII with organoaluminium before application to the gas-phase polymerization reactor.

8. A method of agent application according to any of claims 1 to 6, characterized in that the agent is added into the polymerization reactor before or during gas-phase polymerization on Ziegler-Natta catalysts.

9. A method of agent application according to any of claims 1 to 6, characterized in that the agent is added into the polymerization reactor as a separate component or in a mixture with the precursor of Ziegler-Natta catalyst or in a mixture with organoa!uminium or in a mixture with external donor if used.

10. The agent according to any of claims 1 to 6, characterized in that it is used during gas-phase homopolymerizations of propylene and ethylene, or during gas-phase statistical copolymerizations of propylene with ethylene, ethylene with 1-butene, propylene with 1-butene, ethylene with 1-hexene, propylene with 1-hexene, or during two-stage polymerizations consisting of homopoiymerization of propylene in the liquid phase followed by homopoiymerization of propylene or ethylene in the gas phase, or homopoiymerization of propylene in the gas or liquid phase followed by statistical copolymerization of propylene with ethylene in the gas phase.

11. The agent according to any of claims 1 to 6, characterized in that it is used in discontinuous and continuous processes and in industrial reactors of HSB type (horizontal stirred bed reactors) or in vertically stirred reactors or reactors with vertically stirred fluid bed of polymer and in continuous reactors including a combination of polymerization in the liquid phase with subsequent polymerization in the gas phase.

Description:
AGENT FOR NUCLEATION OF POLYOLEFIN AND ELIMINATION OF FOULING IN A GAS PHASE POLYMERISATION REACTOR

Field of the Invention

The invention concerns an agent, which eliminate the formation of polyolefin powder fouling on the walls of gas-phase reactors and their recycles during the coordination polymerization of 1 -olefins on Ziegler-Natta catalysts, wherein after polymerization this agent remains dispersed in the polyolefin material and acts as a nudeation agent.

State of the Art

Polyolefins, typically represented by polyethylene (PE) and polypropylene (PP) are substances with very low electrical conductivity. The negative property of these non- conductive dielectric materials (i.e., non-conductive, but capable of carrying an electric charge) is the easy generation of static electricity on their surface. The formation of an electrostatic charge on the surface of polyolefin materials is a frequent problem even during the actual synthesis of this material, particularly in gas-phase reactors polymerizing 1 -olefins on Ziegler-Natta (ZN) catalysts. During these polymerization processes there is intense mutual friction of polymeric particles due to fluid or mechanical mixing, and thus electrostatic charge is generated. The fine polymeric particles on the surface of which a sufficiently large electrostatic charge has accumulated, be it a negative or positive one, are naturally attracted to other surfaces with the opposite polarity, which are often the walls of the polymerization reactors passivated with a thin non-conductive layer of polymer and decomposition products of the catalytic systems, which consist in particular of various oxides and hydroxides of aluminium from the decomposition of the organoaluminium catalyst. Electrostatically charged polymeric particles are deposited on the reactor walls and form continuous layers of non-mixed polymeric powder, which then has a tendency to overheat rapidly as a result of the poor removai of heat generated during the exothermic incorporation of the monomeric units of 1 -olefins into polymeric chains occurring inside these polymeric particles. At the same time this layer of polymeric powder acts as a heat insulator, which has a negative impact on temperature regulation and the control of the entire polymerization process.

As a result of the difficult temperature control of the reactor and overheating of the non-mixed polymeric fouling on the reactor walls, the polymeric powder can melt down and form compact agglomerates, which also from time to time break off the walls. So problems can be expected during the circulation of polymeric powder in the reactor and during its subsequent discharge and processing. Other problems can also be observed in the gradual plugging of the entire cooling system, in particular the narrow passages of the cooler. If the electrostatic charge is not removed from the polymeric particles in time, in extreme cases there can be necessary to shutdown of the reactor. For this reason great attention is given to the matter of eliminating electrostatic charge and elimination of polyolefin powder (typically polyethylene or polypropylene) fouling on the walls of a gas-phase polymerization reactor.

The first patent applications concerning procedures for the elimination of fouling on the walls of polymerization reactors were submitted by Phillips Petroleum Co. for the use of small amounts of mixtures of polysulfone, polyamine and oil-soluble sulphonic acid in suspension and lately also in the gas-phase process of ethylene and ethylene/1-hexene co polymerization, see EP0005215 and US5026795.

From the inorganic compounds the frequently patented substances for eliminating the formation of electrostatic charge are water and oxygen, for example patents EP0366823, EP0494316, CZ281858 and US6111034. Beside H 2 0 and 0 2 the ontell company has patented most other inorganic substances as anti-fouling agents: NH3, NO, H 2 S, CO, COS, CS 2 , C0 2 , EP1161465. All of these substances are effective from the anti-fouling aspect, but it is known that they react with an alkylaluminium cocatalyst and/or directly with the Ziegler-Natta catalyst, which leads to an adverse drop in the catalyst's productivity and adverse changes in the properties of the resulting polymer.

Another group of the anti-fouling substances consists of various organic compounds, such as metallic salts of various organic acids, ethoxylated amines, fatty acid esters, diethanolamides, ethoxylated alcohols, alkyl sulfonates, alkyl phosphates etc., for example pursuant to EP0453116, EP1448610, US20050203259, EP2192133, WO2009157770 and WO2009010413. These are mainly substances containing one or more reactive polar groups, such as -OH, -COOH, -SO3H, -NH 2 , -NH-, -CONH 2 , -CONH-, various alkyl phosphates etc., which react either with the organoaluminium cocatalyst or directly with the Ziegler-Natta catalyst, by which its productivity is reduced just as in the case of inorganic anti-fouling compounds.

The common property of all the aforementioned anti-fouling agents is that they often tend to have a negative impact on the properties of the produced polyolefin, and their residues in the polymeric material have no positive effects. But it is known that the properties of polyolefin materials prepared in the aforementioned gas-phase reactors can subsequently be modified by the application of various organic or inorganic substances. Such substances include nucleation agents, which can significantly improve mechanical or optical properties of crystalline polymer by increasing the number of nuclei.

The important group of nucleation agents are highly effective nucleation agents based on derivatives of amides of aliphatic or aromatic carboxylic acids, described for example in patents WO2004/072168, EP0940431 and EP2096137. Compounds allowing the crystallisation of polypropylene in β-crystalline form described in the patents EP0962489, EP0557721 and WO03/102069 constitute a separate group amongst these highly effective nucleating agents.

It is known that the nucleating ability of the agent is given by the specific size and shape of the primary particles of the nucleation agent, so the removal of secondary agglomerates of the primal particles is a highly important parameter for ensuring good nucleation, because due to their size these agglomerates are not able to nucleate. It is also important to prevent the formation of agglomerates of a nucleation agent during the actual dispersion in the polymer matrix. Well performed dispersion is important especially in the case of agents where only a very small amount, ranging from 0.01 - 1.00 wt%, is added to the polymer material.

Post-reactor dispersal of nucleation agents performed in the conventional manner in an extruder is demanding in terms of power and technology. In order to ensure homogeneity it is often necessary to apply intensive mixing in efficient twin screw extruders or at first to prepare the material with high concentration of nucleation agent in the polymer and then dilute it by further granulation with pure polymer to the required level.

In patent application WO2012/045288 there is a description of the method for the application of these nucleation agents into the polymerization without the deactivation of the polymerization Ziegler-Natta catalyst or decomposition of nucleation agent, which allowed the preparation of polyolefin with very well dispersed nudeation agent and improved mechanical and optical properties.

Summary of the Invention

The aim of the invention is to create an agent for the elimination of formation of polyolefin powder fouling on the walls of gas-phase polymerization reactors and their recycles and for the preparation of nucleated polyolefin directly during the polymerization of 1-olefins on Ziegler-Natta catalysts, the subject-matter of which consists mainly of the fact that it contains at least one compound prepared by the reaction of an organoaluminium with a compound on the basis of derivatives of amides of aliphatic or aromatic carboxylic acids.

After the reaction of nudeation agents based on derivatives of amides of aliphatic or aromatic carboxylic acids with organoaluminium these nudeation agents are capable of effective elimination of powder fouling on the walls of the gas-phase reactor without adverse effect on Ziegler-Natta catalyst activity, thereinafter denoted as ZN catalyst. Simultaneously excellent dispersion of the nudeation agent in the polymeric material is obtained, whereby very good nudeation ability is ensured, which is evinced by improved mechanical and optical properties of the produced polyolefin. The introduction of these anti-fouling substances into the polymerization reactor has positive influence on the operation of the gas-phase reactor and besides this also allows production of polymer with very well dispersed nudeation agent, which reduces the costs for reactor operation and for post-reactor processing of produced polymeric material.

A suitable compound on the basis of derivatives of amides of aliphatic or aromatic carboxylic acids is a compound selected from the group of compounds of the general formula I:

wherein k is an integer of 3 or 4, Y 1 is the residue after the elimination of ail carboxyl groups from propane-1 ,2,3-tricarboxylic acid, 1,2,3,4-butanetetracarboxylic acid or 1,3,5-benzenetricarboxyiic acid, Y 2 are three or four of the same or different groups independent of each other consisting of H or linear or branched Ci - C10 alkyl, preferred is H or methyl bounded to cyclohexyl in position 2.

Other preferred compounds on the basis of derivatives of amides of aliphatic or aromatic carboxylic acids are compounds having a structure of general formulas II, 111, IV and V:

wherein !\ I 2 and I 3 or J 1 , J 2 and J 3 or K , K 2 and K 3 or l_\ L 2 and L 3 are independently linear or branched C-i - C 2 o aikyl or unsubstituted C 3 - C 6 cycloalkyl or substituted with 1 , 2, 3, or 4 Ci - C 4 alkyls. I 1 , I 2 and I 3 or J 2 and J 3 or K 1 are independently preferred isopropyl, secondary butyl, tertiary butyl, 1-methylbutyl, 1-methylpentyl, 1- ethyl pentyl,

1.1- dimethylpropyl, 2,2-dimethylpropyl, 1 ,1 -dimethyl butyl, 1 ,1-dimethylhexyl, 1-ehylpropyl, 1-propylbutyl, 1- methyl ethenyl, 1-methyl-2-propenyl, 1-methyl-2-butenyl, cyclopentyl or cyclohexyl. L 1 , L 2 and L 3 or K 2 and K 3 or J 3 are independently preferred isopropyl, secondary buty!, tertiary butyl, 1 ,1-dimethylpropyl, 1 ,2-dimethylpropyl,

2.2- dimethylpropyl, tertiary octyl, cyclopentyl, cyclohexyl, 2-methylcyclohexyl,

2.3- dimethylcyclohexyl, 1-ethylcyclohexyl or 1-adamantyl.

Other preferred compounds on the basis of derivatives of amides of aliphatic or aromatic carboxylic acids of the general formulas VI, VI! and Vl!l are:

wherein in the case of the general formula VI R 1 represents the residue after the elimination of hydroxyl groups of saturated or unsaturated aliphatic C 3 - C 2 o dicarboxylic acids or the residue after the elimination of hydroxyl groups of saturated or unsaturated alicyclic C 6 - C 30 dicarboxylic acids or the residue after the elimination of hydroxyl groups of aromatic C 8 - C 30 dicarboxylic acids. There is a preference for residues after the removal of hydroxyl groups of 1 ,2-ethanedicarboxylic acid, 1 ,3-propanedicarboxylic acid, 1 ,4-butanedicarboxylic acid, 1,5-pentanedicarboxylic acid, 1 ,6-hexanedicarboxylic acid, 1 ,7-heptanedicarboxylic acid, 1 ,8-octanedicarboxyiic acid,

1.4- cyclohexanedicarboxylic acid, 1 ,4-benzenedicarboxylic acid,

1.5- naphthalenedicarboxilic acid, biphenyl-4,4'-dicarboxylic acid and biphenyl-2,2'- dicarboxylic acid. R 2 and R 3 are same or different C 3 - C12 cycloalkyls unsubstituted or substituted by one or more radicals selected from the group Ci - C20 of aliphatic alkyls, C3 - C20 branched alkyls; C2 - C20 aliphatic alkenyls, C3 - C20 branched alkenyls, C 3 - C12 cycloalkyls and phenyls; or C 3 - C 12 cycloalkenyls unsubstituted or substituted by one or more radicals selected from the group C-i - C 20 aliphatic alkyls, C 3 - C 2 o branched alkyls; C 2 - C 2 o aliphatic alkenyls, C 3 - C 2 o branched alkenyls, C 3 - C-i 2 cycloalkyls and phenyls. There is a preference in particular for cyclopentyl, cyclohexyl and phenyl unsubstituted or substituted by methyl or ethyl.

In the case of the compounds of the general formula VII U represents the residue from saturated or unsaturated aliphatic C 2 - C20 diamines, the residue from alicyclic C 4 - C 2B diamines, the residue from heterocyclic C 4 - Cu diamines and the residue from aromatic C 6 - C 2 s diamines. Preferred are especially residues from 1,2-ethanediamine, 1 ,3-propanediamine, 1 ,4-butanediamine, 1 ,5-pentanediamine, 1 ,6-hexanediamine, 1 ,7-heptanediamine, 1 ,8-octanediamine, 1,4-cyclohexanediamine, 1,4-benzenediamine, 1 ,5-naphthalenediamine, biphenyl-4,4'-diamine and biphenyl-2,2'-diamine. U 2 and U 3 are same or different C 3 - C 12 cycloalkyls unsubstituted or substituted by one or more radicals selected from the group Ci - C20 of aliphatic alkyls, C 3 - C 2 o branched alkyls; C 2 - C 2 o aliphatic alkenyls, 0 3 - (¼ο and branched alkenyls, C 3 - Ci 2 cycloalkyls and phenyls; or C 3 - Ci 2 cycloalkenyls unsubstituted or substituted by one or more radicals selected from the group Ci - C20 aliphatic alkyls, C 3 - C 20 branched alkyls; C 2 - C 20 aliphatic alkenyls, (¼ - C zo branched alkenyls, (¾ - C 12 cycloalkyls and phenyls. There is a preference in particular for cyclopentyl, cyclohexyl and phenyl unsubstituted or substituted by methyl or ethyl.

In the case of the compounds of the general formula Vlll V 1 represents the residue from saturated or unsaturated aliphatic C2 - C 2 g amino carboxylic acids, the residue from saturated or unsaturated a!icyclic C 7 - C13 amino carboxylic acids and residue from aromatic C 7 - C15 amino carboxylic acids. Preferred are especially residues from 2-aminoethanoic acid, 3-aminopropanoic acid, 4-aminobutanoic acid, 5-aminopentanoic acid, 6-aminohexanoic acid, 7-aminoheptanoic acid, 8-aminooctanoic acid,

4- aminocyclohexanecarboxylic acid, 4-aminobenzoic acid,

5- aminonaphthalenecarboxylic acid, 4'-amino-4-biphenylcarboxylic acid and 2'-amino-2- biphenylcarboxylic acid. V 2 and V 3 are same or different substituents and V 2 is the same as U 2 or U 3 for the structure of the general formula VII and V 3 is the same as R 2 and R 3 for the structure of the general formula VI.

Compounds based on derivatives of amides of aliphatic or aromatic carboxylic acids suitable after the reaction with organoaiuminium for elimination of polyolefin powder fouling in gas-phase polymerization reactors and preparation of reactor nucleated polyolefin are preferably selected for the group comprising N,N',N"-tris(2- methylcyclohexyl)-1 ,2,3-propanetricarboxyamide, N,N',N"-triscyclohexyl-1 ,2,3- propanetricarboxyamide, N,N',N"-triscyclohexyl-1 ,3,5-benzenetricarboxyamide, N,N , ,N",N"'-tetra(2-methylcyclohexyl)-1,2,3,4-butanetetrac arboxyamide l N,N\N",N"'- tetracyclohexyl-1 ,2,3,4-butanetetracarboxyamide, 1 ,3,5-tris(2,2-dimethylpropaneamino)- benzene, 1 ,3,5-tris(2-ethylbutaneamino)-benzene, 1 ,3,5-tris(2,2-dimethylbutaneamino)- benzene, 1 -isobutaneamino-3,5-bis(pivaloylamino)-benzene, 2,2-dimethylbutaneamido- 3,5-bis(pivaloylamino)-benzene, 2,2-dimethylbutaneamido-3,5-bis(pivaloylamino)- benzene, 1,3-bis(isobutaneamino)-5-pivaloylaminobenzene, 1,3-bis(isobutaneamino)-5- (2,2-dimethylbutane)aminobenzene, 1,3-bis(2,2-dimethylbutaneamino)-5- pivaloylaminobenzene, 1 ,3-bis(2,2-dimethylbutaneamino)-5-isobutaneaminobenzene, 1 ,3-bis(2,2-dimethylbutaneamido)-5-(3,3-dimethylbutane)aminob enzene,

5-pivaloylamino-isophthalic acid N,N'-di-t-butanediamide, 5-pivaloylamino-isophthalic acid N,N'-di-cyclohexanediamide, N-t-butyl-3,5-bis(pivaloylamino)benzeneamide, N-cyclopentyl-3,5-bis(pivaloylamino)benzeneamide, N-cyclohexyl-3,5- bis(pivaloylamino)benzeneamide, N-isopropyl-3,5-bis(pivaloytamino)benzeneamide, N-t-butyl-3,5-bis(2,2-dimethylbutaneamino)benzeneamide ! N,N'-dicyclohexyl-2,6- naphthalenedicarboxyamide, Ν,Ν'-dicyclohexylterephthalamide, N,N'-dicyclohexyl-1,4- cyclohexandicarboxyamide, N,N'-dicyclohexyl-4,4'-biphenyldicarboxyamide, N,N'-bis(p- methylfenyl)hexanediamide, N,N'-bis(p-ethylfenyl)hexanediamide, N,N'~bis(cyclohexylphenol)hexanediamide, N,N ,4-fenylbiscyclohexanecarboxyarnide, N,N'-1,5-naphthalenebisbenzeneamide, N,N'-1,4-cyclohexanebisbenzeneamide and N,N'-1 ,4-cyclohexanebiscyclohexanecarboxyamide. Out of these compounds preference is given in particular to N,N' I N"-tris(2-methylcyclohexyl)-1,2,3- propanetricarboxyamide, 1 ,3 J 5-tris(2,2-dimethyIpropaneamino)-benzene and N.N'-dicyclohexyl^.e-naphthalenedicarboxyamide.

Organoaluminium compounds suitable for the reaction with the compounds described by the general formulas I to VIII have the general formula Q p AlX3 -P , where Q is a linear or branched hydrocarbon chain with 1 to 20 carbon atoms, the compounds with 1 to 6 carbon atoms are preferred. X is a halogen and p can acquire the values 0, 1 , 2 and 3, the preferred halogen is chlorine. The preferred organoaluminium compounds are trimethylaluminium, triethylaluminium, tripropylaluminium, triisopropylaluminium, tributylaluminium, triisobutylaluminium, trihexylaluminium, triisohexyla!uminium, trioktyla!uminium, tridecyialuminium, dimethylaluminium chloride, diethylaluminium chloride, diisobuty!aluminium chloride, methylaluminium dichloride, ethylaluminium dichloride or isobutylaluminium dichloride.

The nucleation agent with anti-fouling properties is prepared by a reaction of compounds described by the general formulas I to VIII with the organoaluminium compound according to invention. It was not possible to exactly identify the structure of the product of nucleation agent based on derivatives of amides of aliphatic or aromatic carboxylic acids reaction with organoaluminium, because the product of this reaction is unstable on air. Due to the exothermic reaction with oxygen and air humidity its decomposition occurs. The exact identification is further complicated by the presence of non-polar hydrocarbon solvent and residues of unreacted organoaluminium. The reaction of nucleation agents with organoaluminium according to the invention is possible to indirectly describe on the basis of the measurement of pressure change caused by a gaseous hydrocarbon released as a consequence of the reaction of organoaluminium with polar groups of the nucleation agent.

It is advantageous to add the organoaluminium in a slight excess against the stoichiometric ratio of the organoaluminium to the polar groups of nucleation agent. It means for example that in the case of nucleation agent with two polar groups is advantageous molar ratio of organoaluminium to nucleation agent 2.0 to 5.0, preferably molar ratio 2.0 to 3.0. In the case of nucleation agent with three polar groups is advantageous molar ratio 3.0 to 6.0, preferably molar ratio 3.0 to 4.0. It is advantageous to perform this reaction before the application into the gas-phase polymerization reactor.

The reaction of nucleation agents based on derivatives of amides of aliphatic or aromatic carboxylic acids with organoaluminium is necessary to perform under the inert atmosphere of nitrogen or argon, preferred is nitrogen. The reason is the sensitivity of organoaluminium to polar substances, with which organoaluminium exothermically reacts. The compounds created by the reaction of organoaluminium with polar substances are not capable of interaction with derivatives of amides of aliphatic or aromatic carboxylic acids.

For safety reasons the reaction of derivatives of amides of aliphatic or aromatic carboxylic acids with organoaluminium is performed in non-polar hydrocarbon and also into the reaction the organoaluminium diluted with the same solvent is added. In the case of reaction of nucleation agent with organoaluminium performed in laboratory scale it is advantageous to utilize organoaluminium diluted by non-polar hydrocarbon to concentration 10 to 200 g/L, however, the concentration is preferred in the range 100 to 200 g/L. Due to the safety reasons in the laboratory is necessary to work with diluted organoaluminium and the reaction with nucleation agent carried out in the non-polar hydrocarbon, however in industrial applications it is convenient do not use the non-polar hydrocarbon and the reaction of organoaluminium with derivatives of amides of aliphatic or aromatic carboxylic acids performed directly with concentrated substances.

Suitable non-polar hydrocarbons for diluting the organoaluminium and performing the reactions with derivatives of amides of aliphatic or aromatic carboxylic acids are hydrocarbons selected from the group comprising liquefied propane, liquefied propylene, liquefied butane, isomers of pentane, hexane, heptane and other C 8 - C 8 linear saturated hydrocarbons, cyc!opentane, cyclohexane, benzene, toluene, xylene and mineral oils. It is also possible to use solutions of concentrated organoaluminiums without dilution in non-polar hydrocarbon and perform the reaction with the selected organic substance without the solvent.

The reaction of derivatives of amides of aliphatic or aromatic carboxylic acids with organoaluminium is suitable to perform according to the invention at temperatures within the range of 10 to 80 °C, preferably 20 to 60 °C. Reactions can be performed at pressure within the range 0.1 to 4.1 MPa (abs.), preferably 0.1 to 0.5 MPa (abs.). It is convenient to perform the reaction under the vigorous stirring for 0.1 to 24 hours, preferred is 0.5 to 3 hours. The product of reaction is necessary to store and also handle under the inert atmosphere, because it also exothermically reacts with polar substances. The reaction with polar substances, such as oxygen, water, alcohols etc., causes the elimination of bonded organoaluminium and recovery of the polar groups, which subsequently negatively affects the activity of ZN catalyst. Thus the concentration of oxygen, water and other polar substances in the inert atmosphere and the non-polar hydrocarbon has to be below 3.0 ppm (vol.), preferably below 1.0 ppm (vol.).

After the reaction with the organoaluminium compound, the nucleation agent with anti-fouling properties can be applied into the polymerization reactor before or during gas-phase polymerization on ZN catalysts, either as a separate component or in a mixture with the precursor of the ZN catalyst or in a mixture with an organometallic cocatalyst or in a mixture with an external donor (if it is used). It is beneficial to add modified anti-fouling nucleating agent into the polymerization reactor separately or in the mixture with organoaluminium cocatalyst.

In the dependence on the non-polar hydrocarbon type it is convenient according to the invention that the concentration of solution or suspension of modified nucleating agent in non-polar hydrocarbon for dosing into the reactor is within the range 0.1 to 300 g/L, preferably 1 to 200 g/L. In the case of solution or suspension in concentrated organoaluminium it is favourable to dilute nucleating agent into organoaluminium in weight ratio of nucleating agent to organoaluminium in the range of 0.01 to 100 g/g, preferably 0.2 to 20 g/g.

In order to eliminate powder fouling on the reactor walls it is advisable to dose anti- fouling nucleator modified by reaction with organoaluminium into polymerization reactor in weight ratio to the amount of dosed 1-olefine, however dose in weight ratio to ZN precursor or organoaluminium cocatalyst is also possible. According to the invention suitable ratio of modified nucleator to 1-olefine is within the range of 0.01 to 00 mg/g, in the case of ethylene polymerization the ratio is preferably in the range of 1.0 to 20 mg/g and in the case of propylene polymerization the ratio is preferably within the range of 0.1 to 10 mg/g. According to the invention suitable ratio of modified nucleator to ZN precursor and to organoaluminium cocatalyst is in the range of 0.01 to 00 g/g, in both cases ratio 0.1 to 30 g/g is preferred. It is advisable to dose the modified nucleator into the reactor in the ratio to 1 -olefin in order to obtain good anti-fouling and nucleating effects. Final concentration of modified nucleator in polymer is in the range of 0.001 to 1.0 wt%, preferably 0.01 to 0.3 wt%.

Ziegler-Natta catalyst is a compound which is created by the reaction of Ziegler-Natta precursor with the organometallic cocatalyst, and in the case of polymerization of propylene and copo!ymerization of propylene with other 1 -olefins also through the reaction with electron donor substances, which increase stereoregularity of the produced polypropylene chain (internal and external donors).

Ziegler-Natta, referred to hereinafter as ZN, precursor is a substance consisting of a compound containing a transition metal from the 4 to 8 group of the periodic table. In general, the ZN precursors are used in soluble form, colloid or as a heterogeneous precipitate or as supported catalyst, where the compound of the ZN precursor is anchored on the surface of a suitable support or filler by a reaction or precipitation. In the case of ZN precursors anchored on the surface of a support, which are intended for polymerization of propylene and copolymerization of propylene with other 1 -olefins, an electron donor compound known as an internal donor is also present on the surface of the support.

The preferred ZN precursors contain Ti, V or Cr, especially Ti, in their structure. The preferred ZN precursors are then halides of titanium, alkoxides of titanium, halides of vanadium and their mutual mixtures, in particular T1CI3, TiCI 4 , mixtures of VOCI 3 with TiCU and mixtures of VCU with TiCI 4 .

Suitable supports for ZN precursors are silica or magnesium compounds such as halides of magnesium, in particular MgC½; also alkoxides of magnesium and dialkyl of magnesium compound, such as diethylmagnesium and organic halides of magnesium such as methylmagnesium chloride, ethylmagnesium chloride and butylmagnesium chloride.

The suitable internal donors for ZN-supported precursors are organic esters such as ethyl benzoate; diesters such as dialkyl phthalates; ethers; di-ethers such as derivatives of 1,3-dimethoxypropane; ketones; amides and their mutual combinations.

Suitable external donors for ZN-supported precursors, which increase stereoregularity of the incorporation of propylene units into the polymer chain during the synthesis of polypropylene and copolymers of propylene with other 1 -olefins, are in general silane compounds or mixtures of various silane compounds, of which preference is given in particular to di-isopropyl-di-methoxy silane (DIPD S), di-isobutyl- di-methoxy silane (DIBDMS), cyclohexylmethyl-di-methoxy silane (CH DMS), di- cyc!opentyl-di-methoxy silane (DCPDMS), isobutyl-isopropyl-di-methoxy silane (IBIPD S), n-propyltriethoxysilane (NPTES) and diethylaminotriethoxysilane (DEATES).

Suitable cocatalysts are organoaluminium compounds with the general formula Q p AlX 3 . p , where Q is a linear or branched hydrocarbon chain with 1 to 20 carbon atoms, compounds with 1 to 6 carbon atoms are preferred. X is a halogen and p can acquire the values 0, 1 , 2 and 3, the preferred halogen is chlorine, and preferred values for the parameter p are 2 and 3. The most preferred cocatalysts are then trimethylaluminium (TMA), triethy!aluminium (TEA), triisobutylaluminium (TIBA), trihexylaluminium (THA) and diethyialuminium chloride (DEAC).

Depending on the type of polymerization technology used and type of ZN precursor, the amount of organoaluminium compound is added into the polymerization reactor in the molar ratio to the transition metal of the ZN precursor in the range of 10 to 1000 mol/mol, 30 to 200 mol/mol is preferred. Depending on the used technology and type of ZN precursor the amount of external donor is added to the polymerization reactor in a molar ratio to the transition metal of the ZN precursor in the range 0.1 to 100 mol/mol or in the molar ratio to the organoaluminium cocatalyst in the range 0.1 to 100 mol/mol, in both cases the preferred molar ratio to the organoaluminium cocatalyst is 1 to 50 mol/mol.

The agents according to the invention allow solving the problem of polyoiefin powder fouling on the gas-phase reactor walls and theirs recycles and production of polyoiefin with very well dispersed nucleating agent, thus the final polymer material, which is leaving the reactor, exhibits improved mechanical and optical properties after the processing. Combination of these two effects provides saving of expenses on operation of polymerization unit and subsequently also on post-reactor processing of produced polymer material.

Agents according to the invention can eliminate polyoiefin powder fouling on the walls of the gas-phase polymerization reactors and produce the reactor-nucleated polymer under all standard gas-phase polymerization conditions. Depending on the polymerization technology, type of ZN catalyst and required properties of the synthesised polyoiefin, gas-phase polymerization of 1-olefins in the presence of anti- fouling nucleation agents can be performed at temperatures ranging from 50 to 120 °C and pressures from 0.5 to 10 MPa, but preferred are the temperatures from 70 to 105°C and pressures from 1 to 4 MPa.

The anti-fouling agents according to the invention can be used for the elimination of fouling on reactor walls and nucleation of polyolefin during gas-phase homopolymerizations of propylene and ethylene, or during gas-phase statistical copolymerization of propylene with ethylene, ethylene with 1-butene, propylene with 1-butene, ethylene with 1-hexene, propylene with 1-hexene, or during 2-stage polymerizations consisting of homopolymerization of propylene in the liquid phase followed by homopolymerization of propylene or ethylene in the gas phase, or homopolymerization of propylene in the gas or liquid phase followed by statistical copolymerization of propylene with ethylene in the gas phase.

Polyolefin powders, where it is convenient to use the agents according to the invention for the elimination of fouling and nucleation, are all the possible products of coordination polymerizations on Ziegler-Natta catalysts involving homopolymers and copolymers of two and more 1-olefins and their mutual mixtures prepared during two- and multi stage polymerizations. Preference is given to homopolymers of propylene and ethylene; statistical copolymers of propylene and ethylene, ethylene and 1-butene, propylene and 1-butene, ethylene and 1-hexene, propylene and 1-hexene; statistical terpolymers ethylene, propylene and 1-butene and ethylene, propylene and 1-hexene; polyolefin powders from two-stage polymerizations involving propylene homopolymerization followed by statistical copolymerization of propylene with ethylene, homopolymerization of propylene followed by statistical copolymerization of ethylene with 1-butene, homopolymerization of propylene followed by statistical copolymerization of ethylene with 1-hexene, homopolymerization of propylene followed by statistical terpolymerization of propylene with ethylene and 1-butene, homopolymerization of propylene followed by statistical copolymerization of propylene with ethylene and 1-hexene. The most preferred polyolefin powders are high density polyethylene (HDPE), linear low density polyethylene (LLDPE), isotactic polypropylene (i-PP), statistical copolymers of propylene with ethylene and polyolefin powders produced during two-stage polymerization consisting of homopolymerization of propylene and statistical copolymerization of propylene with ethylene.

Agents according to the invention are suitable for the reduction of polyolefin powder fouling on reactor walls and production of polyolefin with reactor-dispersed nucleation agent in all types of gas-phase continuous or discontinuous reactors with mechanical or fluid mixed polymer bed. The agents referred to can be applied easily in industrial reactors of the type HSBR (horizontal stirred bed reactors of Ineos company employing the innovene ® technology) or in vertically stirred reactors of the technology Novolen ® utilized by Lummus Novolen Technology or in reactors with vertically stirred polymer fluid bed (Unipoi ® technology of Univation company). Anti-fouling nucleation agents can also be used in continuous industrial reactors including the combination of polymerization in the liquid phase with subsequent polymerization in the gas phase of the type Spheripol ® of Lyondell-Basell or Borstar ® of Borealis.

Preparation of the anti-fouling nucleation agents according to the invention is described in detail in following examples. However the anti-fouling agents according to the invention are not limited only to these particular compounds and include further broad spectrum of comparable compounds that differ from each other in character of individual substituents according to general formulas I to VIM mentioned above.

Brief Overview of Drawings

The invention is clarified with the use of the following figures:

Fig. 1 : Diagram of 2-litre gas-phase polymerization reactor.

Fig. 2: Example of temperature profile in reactor measured at the bottom (Tr) and the cover (Tr2) of the reactor during reference polymerization of ethylene without addition of anti-fouling agent (Example 1.1).

Fig. 3: Picture of bottom of 2-litre reactor after end of reference gas-phase polymerization of ethylene without addition of anti-fouling agent (Example 1.1 ).

Fig. 4: Picture of cover of 2-litre reactor after end of reference gas-phase polymerization of ethylene without addition of anti-fouling agent (Example 1.1 ).

Fig. 5: Example of temperature profile in reactor measured at the bottom (Tr) and at the cover (Tr2) of the reactor during polymerization of ethylene with addition of AF-1a anti- fouling nucleation agent (Example 1.7).

Fig. 6: Picture of bottom of 2-litre reactor after end of gas-phase polymerization of ethylene with addition of AF-1a anti-fouling nucleation agent (Example 1.7)

Fig. 7: Picture of cover of 2-litre reactor after end of gas-phase polymerization of ethylene with addition of AF-1a anti-fouling nucleation agent (Example 1.7). Preferred embodiments of the invention

Examples

Reaction of nucleation agents with organoaluminium was studied using the following methods:

The reaction of the nucleation agents with the organoaluminium was determined on the basis of measuring of the pressure change caused by the reaction of the organoaluminium with the polar groups of the nucleation agent. Measuring was performed in a glass reactor with a total volume of 240 ml_ and equipped with a magnetic stirrer and thermostatic circuit. The reactor was connected to a stainless steel vacuum apparatus which allowed the cleaning of the inner volume of the reactor by evacuation and flushing with pure nitrogen. The pressure inside the reactor was measured using a digital manometer PMA4 (PMA GmbH) with resolution of 10 Pa. The heating of the reactor was ensured by a thermostatic circuit (Julabo HP-4, Julabo Labortechnik GmbH).

The organoaluminium used was triethylaluminium, referred to hereinafter as TEA, where the ethane is released during the reaction with polar substances. For an evaluation of the reaction's intensity there was a reference measurement where for the reaction with TEA { .0 mmol), instead of the nucleation agent, an excess of isopropanol was used (20 ml_ solution isopropanol : heptane = volume ratio 1 : 1). This allowed determining the maximum pressure change caused by the quantitative decomposition of TEA by strongly polar isopropanol.

The procedure for the measurement of the reaction of TEA with nucleation agents NU-1 , NU-2 and NU-3 was as follows: 30 ml_ of heptane and 2 g of nucleation agent was added to a clean glass reactor. Pure nitrogen was bubbled through the mixture at a temperature of 30 °C until approximately 10 mL of heptane had evaporated. The glass reactor was closed with a septum cap, and the pressure inside the reactor was set at 0. 1 MPa (abs.). The temperature inside the reactor was set at the required value and maintained constantly during the whole measurement (as standard 30 °C). After the pressure and temperature had stabilised, a defined amount of TEA solution in heptane was injected into the reactor through the septum using a syringe with a fine metal needle (amount of TEA in the dose 1.0 mmol). After 120 minutes the reached pressure change was read and compared with the pressure change determined in the reference measurement with isopropanol.

For an evaluation of the intensity of polyolefin powder fouling on the walls and cover of the gas-phase polymerization reactor, the following methods were used:

The intensity of polyolefin powder fouling on the walls and cover of the reactor during gas-phase polymerization of 1 -olefins on ZN catalysts was evaluated on the basis of a determination of the difference in the temperatures measured using fast-response thermocouples (Type E) located at the bottom (thermocouple Tr) and cover (thermocouple Tr2) of the polymerization reactor (see Fig. 1). If during polymerization polymer powder fouling on the cover and walls of the reactor is created, the inner surface of the cover and thermocouple Tr2 become covered with a layer of not stirred polymer. This layer has a tendency to overheat as a result of the limited removal of heat, which is generated during the exothermal polymerization reaction. This results in the fact that the temperature measured on thermocouple Tr2 is several degrees higher than the temperature on thermocouple Tr. At the same time the intensity of heat removal from the vapour phase is also decreased as a result of the insulating properties of the layer of polymer fouling. If there is no polymer powder fouling on the walls and cover, the temperature measured on Tr2 is slightly lower than Tr. The lower temperature measured on Tr2 without polymer fouling is caused by heat removal through the uninsulated cover of the reactor. The presence of polymer fouling on the walls of the reactor was also evaluated by directly looking into the reactor after opening it.

An example of the temperature profile measured during gas-phase polymerization on the thermocouple Tr and Tr2 for reference polymerization of ethylene without the addition of anti-fouling agent is shown in Fig. 2. In Fig. 3 and Fig. 4 there are then pictures of polymer fouling on the walls and cover of the reactor after its opening after the same experiment. For comparison, Fig. 5 shows the temperature profile measured on thermocouples Tr and Tr2 for gas-phase polymerization of ethylene in the presence of the nucleation agent NU-1 modified using TEA (i.e., compound AF-1a), where there was no fouling on the reactor walls. Fig. 6 and Fig. 7 show corresponding views of the inside of the reactor after it is opened. The following analytical methods were used for evaluating the influence of nucleation agents on the properties of the synthesised polyolefins:

The melt flow rate (MFR) of polypropylene was measured according to ISO 1133-1 standard at 230 "C and load 2 .6 N. The melt flow rate of polyethylene was measured according to the same standard at a temperature of 190 °C and load of 21.6 N. The measurement of the MFR was performed using a LMI 4004 Dynisco melt indexer. The content of polypropylene soluble in cold xylene (XS) was determined according to ISO 6427 standard. The density of polyethylene was determined according to ISO 1183-1 standard.

The fluff samples were pelletized on a single-screw PLE 651 Brabender extruder (D = 19 mm, L/D=30) at 220 °C and 70 rpm. The polymer was stabilised with 0.2 wt% of Irganox B225. The test specimens were prepared from the pellets using a 320C Arburg Allrounder injection moulding machine. The conditions of injection were configured according to ISO 1873-2. The test specimens were conditioned at 23 °C for 7 days.

The time up to the maximum of crystallisation peak was determined using the method of isothermal crystallisation on a DSC 7 Perkin-Elmer instrument. A sample of 5 - 10 mg of PP (pellets) was sealed in an aluminium pan and heated from 50 °C up to 210 °C and maintained at this temperature for 8 minutes. Then the molten sample was cooled down to the crystallisation temperature (129 °C) at a rate 80 °C/min. When the determined crystallisation temperature was reached, the measurement of the time necessary to reach the maximum of crystallization peak started.

The DSC measurement of 1 st melting, crystallisation and 2 nd melting was done on a DSC Q 100 TA Instruments. A sample of 4 - 10 mg was heated within temperature range 50 - 200 °C. After reaching the temperature of 200 °C, the sample was maintained at this temperature for 10 minutes and then cooled down to 50 °C at the same rate. Immediately after this, the second melting cycle in the same temperature interval was carried out.

The portion of PP crystallised in β-form was determined on the basis of DSC measurement of the 2 nd melting and content of the β-crystalline phase in a sample was then calculated from the enthalpies of melting of a- and β-phase according to the equation (i):

#(%) = ? (β) where j8(%) is the percentage content of PP in the β-form in the sample, c/H m (j8) is the enthalpy of the 2 nd melting for the β-crystalline phase and c/H m (a) is the enthalpy of the 2 nd melting for the a-crystalline phase.

The haze of the polymer material was determined according to ASTM D 1003-00 standard on injection moulded plates with dimensions of 113x113 mm and 1 mm thick, measured on a 650 Datacoior spectrophotometer. The tensile modulus was determined according to ISO 527 and the flexural modulus was determined according to ISO 178, the measurement was performed on a 4302 Instron.

Example 1

Modification of nucleation agent NU-1 for application as anti-fouling agent AF-1a into polymerization:

3.0 g N,N',N"-tris(2-methylcyclohexyl)-1 ,2,3-propanetricarboxyamide, referred to hereinafter as NU-1 , this substance is commercially available under the name Rikaclear PC-1 , was mixed with 20 ml_ of n-heptane in a sealable glass vessel containing a teflon magnetic stirrer. Then, with constant stirring, pure nitrogen was bubbled through the suspension at 80 - 90 °C until at least 90 % of n-heptane had distilled out. After cooling down, 2.6 g of triethylaluminium (TEA), diluted for safety reasons in n-heptane (concentration 195 g/L), was gradually added to NU-1 under a protective atmosphere of nitrogen. The mixture was stirred for 2 hours at laboratory temperature. Resultant molar ratio NU-1 : TEA = 1 : 3.5. The reaction of NU-1 with TEA is exothermic, thus the solution heats up spontaneously to 40 - 60 °C. After reaction ending the solution spontaneously cooled down to 23 °C. During the reaction a gaseous ethane was releasing. Ethane was removed out of the reaction vessel in order to carry out the reaction under pressure of 0.1 Pa (abs.). The reaction of NU-1 with TEA results in the formation of a non-polar anti-fouling agent with nucleation abilities, referred hereinafter as AF-1a, which is soluble in hydrocarbons, forming colourless solutions. After 2 hours of stirring the solution with AF-1a is concentrated by distilling off part of n-heptane by bubbling with pure nitrogen at a temperature of 80 - 90 °C to a concentration of 150 - 200 g/L. The solution AF-1 a in n-heptane is stored under an inert nitrogen atmosphere.

A confirmation of the reaction of TEA with NU-1 was performed using the measurement of pressure change, which is caused by released ethane, if there is a reaction of TEA with the polar groups of NU-1. By a comparison of the pressure change determined in the case of reference reaction of TEA with isopropanol it was observed that in the case of the reaction of TEA with NU-1 there is a pressure change corresponding to approximately 35 % of the pressure change caused by the reaction of TEA with isopropanol (both measurements performed at 30 °C). Thus the measurement confirmed that TEA reacts with the polar -CONH- groups of NU-1 and forms a new structure. The amount of released ethane corresponds to approximately 1/3 of the total amount of ethane which can be released from TEA by the reaction with polar substances. It can be concluded that in the majority of cases an independent TEA molecule reacts with each -CONH- group of NU-1 , so only one ethyl group is split off from each TEA.

Example 2

Modification of nucleation agent NU-1 for application as anti-fouling agent AF- b into polymerization:

The procedure for the modification of the nucleation agent NU-1 is the same as the procedure described in Example 1 , but with the difference that after bubbling through the suspension of N,N',N"-tris(2-methylcyclohexyl)-1 ,2,3-propanetricarboxyamide in heptane at 80 - 90 °C this suspension was placed into thermostat (Labio CTB 06C) and cooled down to 10 °C. After cooling down to 10 °C, the same amount of TEA as in Example 1 was gradually added to the suspension. At this low temperature the reaction proceeded apparently slowly than in the case described in Example 1 , thus mixture had to be stirred for 24 hours or until nucleation agent reacted with TEA completely and colourless solution was obtained.

Example 3

Modification of nucleation agent NU-1 for application as anti-fouling agent AF-1c into polymerization:

The procedure for the modification of the nucleation agent NU-1 is the same as the procedure described in Example 1 , but with the difference that after bubbling through the suspension of N,N',N"-tris(2-methylcyclohexyl)-1 ,2,3-propanetricarboxyamide in heptane at 80 - 90 °C this suspension was placed into thermostat (Labio CTB 06C) and cooled down to 70 °C. After cooling down to 70 °C, the same amount of TEA as in Example 1 was gradually added to the suspension. The rate of reaction was high and gaseous ethane was intensively released. In comparison with the modification of anti- fouling agent described in Example 1 , this mixture was necessary to stir only 15 min until nucleation agent reacted with TEA completely and colourless solution was obtained.

Example 4

Modification of nucleation agent NU-1 for application as anti-fouling agent AF-1d into polymerization:

The procedure for the modification of the nucleation agent NU-1 is the same as the procedure described in Example 1 , but with the difference that modified nucleating agent AF-1d was afterwards transferred into a pressure stainless steel vessel of 6 L volume. The stainless steel vessel was equipped with mechanical stirrer, thermocouple for the temperature measurement inside the vessel, digital manometer, thermostatic circuit with temperature regulation, iniet for dosing placed in the vessel cover and outlet placed on the vessel bottom. The stainless steel vessel was connected to the line with pure nitrogen and liquid propylene.

Before of agent AF-1d introduction, the vessel was flushed with nitrogen stream at 95 °C for approximately 45 min. After cooling down the vessel to 40 °C, 2 g of the modified nucleating agent AF-1d diluted in heptane on concentration of 150 - 200 g/L was added under nitrogen flow. Then the vessel was closed and 2 L of liquid propylene was added, which further diluted the nucleating agent AF-1d to the concentration of 1 g/L. The pressure stainless steel vessel was heated up under the permanent stirring to 60 C C, through which the pressure inside the vessel was set up at approximately 2.6 MPa.

Example 5

Modification of nucleation agent NU-2 for application as anti-fouling agent AF-2 into polymerization:

The procedure for the modification of the nucleation agent NU-2 and preparation of non-polar anti-fouling agent with nucleation abilities AF-2 is the same as the procedure for the modification of the nucleation agent NU-1 , but with the difference that for the reaction 3.0 g of 1 ,3,5-tris(2,2-dimethylpropaneamido)-benzene, referred to hereinafter as NU-2, was used. This substance is commercially available as Irgaclear XT-386. Then 3.2 g of TEA is gradually added, thus the resultant molar ratio NU-2 : TEA = 1 : 3.5. The reaction of NU-2 with TEA results in the formation of the anti-fouling agent, referred to hereinafter as AF-2, which has limited solubility in hydrocarbons and forms a white to milky coloured suspension.

A confirmation of the reaction of TEA with NU-2 was performed using the measurement of pressure change, which is caused by released ethane, if there is a reaction of TEA with the polar groups of NU-2. The amount of released ethane corresponded to approximately 38 % of the total amount of ethane released during the reference reaction of TEA with isopropanol (both measurements were performed at 30 °C). It can be concluded that the reaction occurs in a manner similar to that in the case of NU-1 , where in the majority of cases an independent TEA molecule reacted with each -CONH- group of NU-1 , so only one ethyl group is split off from each TEA.

Example 6

Example of modification of nucleation agent NU-3 for application as anti-fouling agent AF-3 into polymerization:

The procedure for the modification of the nucleation agent NU-3 and preparation of non-polar anti-fouling agent with nucleation abilities AF-3 is the same as the procedure described in Example 1 , but with the difference that for the reaction 3.0 g of N.N'-dicyclohexylnaphthalene^.e-dicarboxyamide, referred to hereinafter as NU-3, was used. This substance is commercially available under the name NJ Star NU-100. Then 2.7 g of TEA is gradually added thus the resultant molar ratio NU-3 : TEA = 1 : 3.0. The reaction of NU-3 with TEA results in the formation of the anti-fouling agent, referred to hereinafter as AF-3, which has limited solubility in hydrocarbons and forms a yellow to orange coloured suspension.

A confirmation of the reaction of TEA with NU-3 was performed using the measurement of pressure change, which is caused by released ethane, if there is a reaction of TEA with the polar groups of NU-3. The amount of released ethane corresponded to approximately 30 % of the total amount of ethane released during the reference reaction of TEA with isopropanol (both measurements were performed at 55 °C). It can be concluded that the reaction occurs in the same way as in the case of NU-1 and NU-2, where in the majority of cases an independent TEA molecule reacts with each -CONH- group of NU-3, and in this reaction only one ethyl group is split off from each TEA. Examples of performance of gas-phase polymerizations

Example 1.1

Reference gas-phase polymerization of ethylene

A gas-phase polymerization of ethylene was performed in a stainless steel discontinuous bed reactor with a volume of 2 litres equipped with a spiral-shaped stirrer driven by an electric motor via a magnetic clutch (see diagram of reactor in Fig. 1 ). The reactor was connected to a thermostatic circuit allowing the regulation of the temperature, which is controlled by the external PID regulator. The flows of ethylene and hydrogen were regulated via Bronkhorst mass flow controllers. Then the amount of added ethylene and hydrogen was determined by integration of the flow. The pressure in the reactor was measured using a digital manometer from P A GmbH company and the temperature in the lower (Tr) and upper part (Tr2) of the reactor was measured by E type thermocouples from Omega. The operation of mass flow controllers and data acquisition was ensured by an external microprocessor managed by operating software on the PC.

During the cleaning procedure a stream of nitrogen was flushing the reactor at 95 °C for approximately 30 minutes. Then there was a pressure test to check the leak tightness (30 minutes at 95 °C and 3,0 Pa of ethylene). After the pressure test the reactor was cooled down to 40 °C, the stirring was switched off and 0.6 mmol of cocatalyst (triethylaluminium - TEA) was added. TEA was added diluted in n-heptane (concentration 1.7 mmol/mL). During the addition of components the inner volume of the reactor was protected from contamination by a stream of nitrogen. Following the addition of all components the reactor was closed and filled with 0.6 MPa (abs.) nitrogen, 280 mmol hydrogen and 3.2 g ethylene.

Polymerization was initiated by injecting the ZN precursor into the reactor using a dosing device allowing the introduction of the ZN precursor into the pressurised reactor by liquid ethylene. In order to flush the ZN precursor into the reactor by liquid ethylene the dosing device together with ca. 5 mL reservoir was cooled down to a temperature of approximately -10 °C.

The ZN precursor used for the gas-phase polymerization of ethylene was a commercial TiCi /tetrahydrofuran/MgCl 2 type diluted in mineral oil, referred to hereinafter as precursor ZN-1. 0.126 mL of ZN-1 suspension, i.e., 30 mg of dry precursor ZN-1 , was sampled into the dosing device. The precursor ZN-1 was then flushed into the reactor in 5 doses of 4 g of liquid ethylene at 60 s intervals. The precursor ZN-1 was added into the reactor stabilised at the temperature of 50 °C, then it took less than 5 minutes to reach the polymerization temperature. The speed of stirring before and after polymerization was 500 rpm. The composition of the gas phase was analysed every 30 minutes for the duration of polymerization using a Clarus 500 Perkin- Elmer gas chromatograph. Polymerization was performed at 100 °C and a pressure of 2.3 MPa.

The entire process of start-up and main polymerization was controlled and monitored by a computer. After the required polymerization temperature and pressure were reached, these conditions were maintained at the required level for the entire duration of polymerization. In the case of pressure this was by continuous dosing with a monomer (ethylene). The composition of the gas phase during polymerization was approximately 50 mol.-% of ethylene, 20 mol.-% of hydrogen and 30 mol.-% of nitrogen.

The polymerization time was 120 minutes. At the end of polymerization the reactor was carefully depressurised and the residual ethylene and TEA were removed by several times repeated filling with nitrogen to 0.5 MPa. Then the polymer powder was removed from the reactor, weighed and dried at 70 °C for 2 hours in a vacuum drier.

Example 1.2

Comparative gas-phase polymerization of ethylene with addition of commercial anti-fouling agent

Polymerization was performed under the same conditions as the reference polymerization described in Example 1.1, but with the difference that after the dosage of TEA solution, 20 mL of nitrogen saturated with water vapour at 23°C, which corresponds to 0.4 mg of distilled water, was added. Dosing was performed via a chromatographic loop from Valco Instruments with a volume of 10 mL (dose 2 x 10 mL). Pressure in the loop was 0.1 MPa (abs.). Volume of the loop was each time flushed out with 1.6 g of gaseous ethylene, thus together with nitrogen saturated with water vapour also overall 3.2 g of ethylene was dosed into the reactor. Subsequently before the dosage of precursor ZN-1 no further ethylene was added. Example 1.3

Comparative gas-phase polymerization of ethylene with addition of commercial anti-fouling agent

Polymerization was performed under the same conditions as the reference polymerization described in Example 1.1 , but with the difference that after the dosage of TEA solution, 0.006 mg of oxygen (purity 99.5 %) was added at laboratory temperature into the reactor via a chromatographic loop from Valco Instruments with a volume of 0.005 mL. Pressure of oxygen in the ioop was 0.1 Pa (abs.). Volume of the loop was flushed out into the reactor with 3.2 g of gaseous ethylene. Subsequently before the dosage of precursor ZN-1 no further ethylene was added.

Example 1.4

Comparative gas-phase polymerization of ethylene with unmodified nucleation agent NU-1

Polymerization was performed under the same conditions as the reference polymerization described in Example 1.1 , but with the difference that after the dosage of TEA solution, 131 mg of N,N' I N"-tris(2-methylcyclohexyl)-1,2,3-propanetricarboxyami de (NU-1) diluted in n-heptane under an inert nitrogen atmosphere (concentration 150 - 200 g/L) was added to the reactor.

Example 1.5

Comparative gas-phase polymerization of ethylene with unmodified nucleation agent NU-2

Polymerization was performed under the same conditions as the reference polymerization described in Example 1.1 , but with the difference that after the dosage of TEA solution, 68 mg of 1 ,3,5-tris(2,2-dimethylpropaneamino)-benzene (NU-2) diluted in n-heptane under an inert nitrogen atmosphere (concentration 150 - 200 g/L) was added to the reactor.

Example 1.6

Comparative gas-phase polymerization of ethylene with unmodified nucleation agent NU-3 Polymerization was performed under the same conditions as the reference polymerization described in Example 1.1 , but with the difference that after the dosage of TEA solution, 132 mg of N,N'-dicyc!ohexyl-2,6-naphthalendicarboxyamide (NU-3) diluted in n-heptane under an inert nitrogen atmosphere (concentration 150 - 200 g/L) was added to the reactor.

Example 1.7

Gas-phase polymerization with modified nucleation agent AF-1a

Polymerization was performed under the same conditions as the reference polymerization described in Example 1.1 , but with the difference that after the dosage of TEA solution, 130 mg of the compound AF-1a as a solution in n-heptane (concentration 150 - 200 g/L) was added to the reactor.

Example 1.8

Gas-phase polymerization with modified nucleation agent AF-1b

Polymerization was performed under the same conditions as the reference polymerization described in Example 1.1 , but with the difference that after the dosage of TEA solution, 65 mg of the compound AF-1b as a solution in n-heptane (concentration 150 - 200 g/L) was added to the reactor.

Example 1.9

Gas-phase polymerization with modified nucleation agent AF-1c

Polymerization was performed under the same conditions as the reference polymerization described in Example 1.1 , but with the difference that after the dosage of TEA solution, 131 mg of the compound AF-1c as a solution in n-heptane (concentration 150 - 200 g/L) was added to the reactor.

Example 1.10

Gas-phase polymerization of ethylene with modified nucleation agent AF-2

Polymerization was performed under the same conditions as the reference polymerization described in Example 1.1 , but with the difference that after the dosage of TEA solution, 65 mg of the compound AF-2 as a suspension in n-heptane (concentration 150 - 200 g/L) was added to the reactor. Example 1.11

Gas-phase polymerization of ethylene with modified nucieation agent AF-3

Polymerization was performed under the same conditions as the reference polymerization described in Example' 1.1 , but with the difference that after the dosage of TEA solution, 131 mg of the compound AF-3 as a suspension in n-heptane (concentration 150 - 200 g/L) was added to the reactor.

Example 2.1

Reference gas-phase polymerization of propylene

Gas-phase polymerization of propylene was performed in a stainless steel discontinuous bed reactor with a volume of 2 litres equipped with a spiral-shaped stirrer driven by an electric motor via a magnetic clutch (see diagram of reactor in Fig. 1). The reactor was connected to a thermostatic circuit allowing the regulation of the temperature, which is controlled by the externa! PID regulator. The amount of added propylene before and during polymerization was measured according to the change of weight of storage pressure cylinder with monomer. The flows of propylene and hydrogen were regulated via Bronkhorst mass flow controllers. Then the amount of added hydrogen was determined by integration of the flow. The pressure in the reactor was measured using a digital manometer from PMA GmbH company, and the temperature in the lower (Tr) and upper part (Tr2) of the reactor was measured by E type thermocouples from Omega. The operation of mass flow controllers and data acquisition was ensured by an external microprocessor managed by operating software on the PC.

During the cleaning procedure a stream of nitrogen was flushing the reactor at 95 °C for approximately 30 minutes. Then there was a pressure test to check the leak tightness (30 minutes at 95 °C and 3.0 Pa of propylene). After the pressure test the reactor was cooled down to 40 °C, stirring was switched off and 0.2 mmol of cocatalyst (triethyialuminium - TEA) and 0.02 mmol of external donor (di-i-butyldimethoxy silane - DIBDMS) were added. TEA and DIBD S were added diluted in n-heptane (concentration of TEA was 1.7 mmol/mL and concentration of DIBDMS 0.2 mmol/mL). During the addition of components the inner volume of the reactor was protected from contamination by a stream of nitrogen. Following the addition of all components the reactor was closed and filled with 50 g of propylene and 10 mmo! of hydrogen. The partial pressure of the residual nitrogen in the reactor was approximately 0.1 MPa (abs.). Polymerization was initiated by injecting the ZN precursor into the reactor using a dosing device allowing the introduction of the ZN precursor into the reactor pressurized by liquid propylene.

The ZN precursor used for the gas-phase polymerization of propylene was a commercial TiCWdi-i-butylphthalate/MgCb type diluted in mineral oil, referred to hereinafter in as precursor ZN-2. 0.026 ml_ of ZN-2 suspension, i.e., 6 mg of dry precursor ZN-2, was sampled into the dosing device. The precursor ZN-2 was then flushed into the reactor by 40 g of liquid propylene. The precursor ZN-2 was added into the reactor stabilised at the temperature of 50 °C, then it took less than 5 minutes to reach the polymerization temperature. The speed of stirring before and during polymerization was 500 rpm. The polymerization time was 60 minutes. The composition of the gas phase was analysed every 5 minutes for the duration of polymerization using a Clarus 500 Perkin-Elmer gas chromatograph. Polymerization was performed at 75 °C and pressure of 2.3 MPa.

The entire process of start-up and main polymerization was controlled and monitored by a computer. After the required polymerization temperature and pressure were reached, these conditions were maintained at the required level for the entire duration of polymerization. In the case of pressure this was by continuous dosing with a monomer (propylene). Depending on the consumption of propylene during polymerization hydrogen was added continuously, by which its constant concentration was maintained in the gas phase during whole polymerization. The composition of the gas phase during polymerization was approximately 0.5 mol.-% of hydrogen, 92.0 mol.-% of propylene, and 7.5 mol.-% of nitrogen.

At the end of polymerization the reactor was carefully depressurised and the residual propylene and TEA were removed by several times repeated filling with nitrogen to 0.5 MPa. Then the polymeric powder was removed from the reactor, weighed and dried at 70 °C for 2 hours in a vacuum drier.

Example 2.2

Comparative gas-phase polymerization of propylene with addition of commercial anti-fouling agent Polymerization was performed under the same conditions as the reference polymerization described in Example 2.1 , but with the difference after addition of solutions of TEA and DIBDMS, 8.0 mg of Atmer 163 as a solution in n-heptane (concentration 40 - 80 g/L) was added to the reactor.

Example 2.3

Gas-phase polymerization of propylene with modified nucleation agent AF-1a

Polymerization was performed under the same conditions as the reference polymerization described in Example 2.1 , but with the difference that after addition of solutions of TEA and DIBDMS, 32 mg of the compound AF-1a as a solution in n-heptane (concentration 50 - 200 g/L) was added to the reactor.

Example 2.4

Gas-phase polymerization of propylene with modified nucleation agent AF-1b

Polymerization was performed under the same conditions as the reference polymerization described in Example 2.1 , but with the difference that after addition of solutions of TEA and DIBDMS, 31 mg of the compound AF-1b as a solution in n-heptane (concentration 150 - 200 g/L) was added to the reactor.

Example 2.5

Gas-phase polymerization of propylene with modified nucleation agent AF- c

Polymerization was performed under the same conditions as the reference polymerization described in Example 2.1, but with the difference that after addition of solutions of TEA and DIBDMS, 31 mg of the compound AF-1c as a solution in n-heptane (concentration 150 - 200 g/L) was added to the reactor.

Example 2.6

Gas-phase polymerization of propylene with modified nucleation agent AF-1d

Polymerization was performed under the same conditions as the reference polymerization described in Example 2.1 , but with the difference that to the reactor was connected the bottom outlet of the stainless steel pressure vessel containing AF-1d compound in solution of liquid propylene (concentration 1 g/L). After addition of solutions of TEA and DIBDMS, 32 mg of AF-1a compound diluted in liquid propylene was added to the reactor. Amount of AF-1d solution in liquid propylene added to the reactor was measured by Bronkhorst liquid mass flow controller and correspond to 16 g of liquid propylene. Another 34 g of propylene was added to the reactor before the introduction of ZN-2 precursor in order to have inside the reactor 50 g of propylene in total.

Example 2.7

Gas-phase polymerization of propylene with modified nucleation agent AF-2

Polymerization was performed under the same conditions as the reference polymerization described in Example 2.1 , but with the difference that after addition of solutions of TEA and DIBD S, 142 mg of the compound AF-2 as a suspension in n-heptane (concentration 150 - 200 g/L) was added to the reactor.

Example 2.8

Gas-phase polymerization of propylene with modified nucleation agent AF-3

Polymerization was performed under the same conditions as the reference polymerization described in Example 2.1 , but with the difference that after addition of solutions of TEA and DIBDMS, 141 mg of the compound AF-3 as a suspension in n-heptane (concentration 150 - 200 g/L) was added to the reactor.

Example 3.1

Example of synthesis of reference homopolymer of propylene in 50-litre reactor

For a determination of the mechanical and optical properties a polypropylene synthesis was performed in a stainless steel discontinuous bed reactor with a volume of 50 litres equipped with spiral-shaped stirrer driven by an electric motor via a magnetic clutch. Polymerization in the gas phase was performed at a pressure 2.2 Pa and temperature 75 °C.

Before each polymerization the reactor was evacuated for a period of 30 minutes at 85 °C and then flushed out seven times by pressurizing with nitrogen to 0.8 - 1.0 MPa. After this cleaning procedure, cooling of the reactor to the temperature suitable for the dosing of the ZN precursor followed. The temperature for catalyst dosing was selected on 35 °C. During the cooling the reactor was flushed out another three times with nitrogen.

Then the reactor was dosed with 3.4 mmol of cocatafyst (triethylaluminium - TEA) and 0.34 mmol of external donor (di-i-butyldimethoxy silane - DIBDMS). TEA and DIBDMS solutions were added diluted in n-heptane (concentration of TEA was 1.7 mmoi/mL and concentration of DIBDMS 0.6 mmoi/mL). Following the addition of all components the reactor was closed and filled with 2.0 kg of propylene and 0.1 mol of hydrogen. The partial pressure of the residual nitrogen in the reactor was approximately 0.1 MPa (abs.).

Polymerization was initiated by injecting the ZN precursor into the reactor using a dosing device allowing the introduction of the ZN precursor into a reactor pressurized by liquid propylene. The ZN precursor used for the gas-phase polymerization of propylene in the 50-litre reactor was the same commercial TiCI di-i-butylphthalate/MgCb type as was used in the gas-phase polymerizations of propylene in 2-litre reactors, and was also diluted in mineral oil. In the text this precursor is also marked as precursor ZN-2. 0.43 mL of ZN-2 suspension, i.e., 100 mg of dry precursor ZN-2, was sampled into the dosing device. The precursor ZN-2 was then flushed into the reactor with 0.5 kg of liquid propylene.

After the dosing of catalyst the reactor was heated up to the polymerization temperature and pressure. Subsequently after the reach of 95 % of the polymerization pressure the measurement of the time of the actual polymerization began. Polymerization was performed in a mechanically mixed bed in the gas phase.

The entire process of start-up and main polymerization was controlled and monitored by a computer. After the required polymerization temperature and pressure were reached, these conditions were maintained at the required level for the entire duration of polymerization. In the case of pressure this was by continuous dosing with a monomer (propylene). Depending on the consumption of propylene, during polymerization hydrogen was added continuously, by which its constant concentration was maintained in the gas phase during whole polymerization. When the defined consumption of propylene was reached, the flow of the monomer was closed and the polymerization reaction was terminated by the addition of oxygen (100 mmol) to the reactor. Then the reactor was degassed and flushed out three times by pressurizing with nitrogen to 0.8 - 1.0 MPa. After the reactor was opened, the polymeric powder was weighed and dried at 70 °C for 2 hours in a vacuum drier.

Example 3.2

Example of synthesis of homopolymer of propylene in 50-iitre reactor containing nucleation agent with anti-fouling properties AF-1a Polymerization was performed under the same conditions as the reference polymerization described in Example 3.1 , but with the difference that after addition of solutions of TEA and DIBDMS, 3.0 g of the compound AF-1 a as a solution in n-heptane (concentration 150 - 200 g/L) was added to the reactor. Polymerization was terminated after the reach of the defined consumption of propylene corresponding to the yield of 3.0 kg PP.

Example 3.3

Example of synthesis of homopolymer of propylene in 50-litre reactor containing nudeation agent with anti-fouling properties AF-2

Polymerization was performed under the same conditions as the reference polymerization described in Example 3.1 , but with the difference that after addition of solutions of TEA and DIBDMS, 0.9 g of the compound AF-2 as a suspension in n-heptane (concentration 150 - 200 g/L) was added to the reactor. Polymerization was terminated after the reach of the defined consumption of propylene corresponding to the yield of 3.0 kg PP.

Example 3.4

Example of synthesis of homopolymer of propylene in 50-litre reactor containing nudeation agent with anti-fouling properties AF-3

Polymerization was performed under the same conditions as the reference polymerization described in Example 3.1 , but with the difference that after addition of solutions of TEA and DIBDMS, 0.9 g of the compound AF-3 as a suspension in n-heptane (concentration 150 - 200 g/L) was added to the reactor. Polymerization was terminated after the reach of the defined consumption of propylene corresponding to the yield of 3.0 kg PP.

The influence of the compounds AF-1a, AF-1 b, AF-1c, AF-2 and AF-3 prepared through the reaction of nudeation agents NU-1, NU-2 and NU-3 with triethylaluminium on the behaviour of the ZN catalysts and ability to eliminate polymer powder fouling on the cover and walls of the reactor during the gas-phase polymerization of ethylene was studied in a 2-litre gas-phase reactor. The results are summarised in Tab. 1. In this table there is also a comparison of the reference gas-phase polymerization of ethylene without addition of anti-fouling agent (Example 1.1 ) with polymerization performed in the presence of modified nucleation agents AF-1a, AF-1b, AF-1c, AF-2 and AF-3 (Examples 1.7 - 1.11 ). In addition there is also shown the comparison with the polymerizations performed with the original nucleation agents (NU-1, NU-2 and NU-3 - Examples .4 - 1.6) and with the polymerizations performed with industrially used anti- fouling compounds (H 2 0 and O2 - Examples 1.2 and 1.3).

The results in Tab. 1 show that for a reference polymerization without anti-fouling agent the temperature difference measured on the thermocouples Tr (bottom of reactor) and Tr2 (cover of reactor) was +3.4 °C, which indicates the presence of polymer fouling on the reactor cover (see Fig. 2). In contrast the gas-phase polymerization of ethylene performed in the presence of the agents AF-1a, AF-1 b, AF-1c, AF-2 and AF-3 have slightly negative temperature difference measured on the thermocouples Tr and Tr2. The negative difference means that thermocouple Tr2 located on the reactor cover is measuring a lower value than thermocouple Tr as a result of the heat being conducted away through the uninsulated reactor cover. This observation represents evidence that during the gas-phase polymerization of ethylene in the presence of the agents AF-1a, AF-1b, AF-1 c, AF-2 and AF-3 polyethylene fouling is not deposited on the cover and walls of the reactor. An example of the temperature profile measured on thermocouples Tr and Tr2 during gas-phase polymerization of ethylene in the presence of nucleation agent AF-1a and view inside the reactor after its opening is given in Fig. 5, Fig. 6 and Fig. 7. A comparable anti-fouling effect (negative Tr2-Tr) was also observed in the case of the unmodified nucleation agents NU-1 , NU-2 and NU-3 and industrially used anti- fouling compounds (H 2 0, 0 2 ). However, from the results given in Tab. 1 it is evident that the polymerization of ethylene in the presence of nucleation agents AF-1a, AF-1b, AF- 1c, AF-2 and AF-3 (modified by the reaction with triethylaluminium) has an activity of the catalyst comparable with, and in some cases higher than, was determined in the case of the reference polymerization, whereas in the case of the nucleation agents NU-1, NU-2, NU-3 and industrially used anti-fouling agents (H 2 0, O2) there is a significant drop in activity.

In comparison with the reference polymerization, in the presence of nucleation agents with anti-fouling effects (AF-1a, AF-1b, AF-1c, AF-2 and AF-3) polyethylene with higher melt flow rate and density on the ZN catalyst was prepared, which in both cases are positive changes improving the properties of PE. In the case of industrial anti-fouling agents (H 2 0, 0 2 ) and not modified nucleation agents NU-1 , NU-2 and NU-3 the melt flow rate and density of PE were lower in most cases than for the reference polymer. The results of tests on nucleation agents with anti-fouling effects AF-1 a, AF-1b, AF-1c, AF- d, AF-2 and AF-3 in gas-phase polymerization of propylene in a 2-litre reactor are given in Tab. 2 (Examples 2.3 - 2.8). Here there is also shown a comparison with the reference experiment without anti-fouling agent (Example 2.1 ) and experiment with industrially used anti-fouling agent Atmer 163 (Example 2.2).

From Tab. 2 it is evident that the nucleation agent modified by a reaction with triethylaluminium (AF-1a, AF-1b, AF-1c, AF-1d, AF-2 and AF-3) effectively prevents the polymer powder fouling even in the case of gas-phase polymerization of propylene (negative difference Tr2-Tr). In the case of reference polymerization this difference was +2.8 °C. A comparison with the commercial anti-fouling agent Atmer 163 shows that during the use of modified nucleation agents (AF-1a, AF-1 b, AF-1c, AF-1d, AF-2 and AF-3) there is no deactivation of the catalyst and drop in polymerization activity even when there are higher doses of these compounds in the polymerization.

Polypropylene prepared in the presence of nucleation agents with anti-fouling effects (AF-1 a, AF-1 b, AF-1c, AF-1d, AF-2 and AF-3) has a slightly higher melt flow rate and comparable content of XS. The higher me!t flow rate indicates that in the presence of these agents hydrogen is more efficient, which is a positive effect. From Tab. 2 it is evident that in the case of the commercial Atmer 163 the situation is quite the opposite, and its presence in polymerization reduces the polymer's melt flow rate. Through the evaluation of the times necessary to reach the maximum of crystallisation peak it was proven that polymers prepared in the presence of the compounds AF-1 a, AF-1b, AF-1c, AF-1d, AF-2 and AF-3 have such times significantly shorter, which means that nucleation of PP is significantly faster than in the case of the reference polymer. As is further evident from Tab. 2, in the case of Atmer 163 the rate of crystallisation is comparable with the reference polymerization. This result shows that in comparison with the compounds AF-1 a, AF-1b, AF-1c, AF-1d, AF-2 and AF-3 Atmer 163 does not have the ability to nucleate PP and thus influence its mechanical or optical properties, so it's only one purpose in polymerization is the elimination of fouling on reactor walls.

According to the results of the tests in 2-litre reactor the behaviour of agents AF~1b, AF-1c and AF-1d is identical with agent AF-1a. Since for their preparation the same nucleating agent NU-1 was used and differs only in the temperature, at which the reaction with triethylaluminium was carried out (AF-1b and AF-1c), or manner of dilution was used (AF-1d), it is assumed that their impact on mechanical and optical properties is the same as in the case of AF-1 a. Thus for evaluation of the influence of nucleating agents with anti-fouling effects on mechanical and optical properties of polypropylene, only AF-1a, AF-2 and AF-3 were utilized.

For this purpose polymerizations in a 50-litre gas-phase reactor were performed. In the case of polymerization in the 50-litre reactor it was not possible to evaluate the influence of the agents AF-1a, AF-2 and AF-3 on the formation of polymer powder fouling on the reactor walls, but it was possible to prepare a sufficient amount of polymer (approximately 3 kg) for evaluation of mechanical (Tensile and Flexural moduli) and optical properties (Haze). The results are summarised in Tab. 3, where it is shown that in comparison with the reference polymerization the polypropylene prepared in the presence of the agents AF-1a, AF-2 and AF-3 has significantly faster crystallisation and noticeably higher values for Tensile and Flexural moduli, in the case of nucieation agents with anti-fouling effects AF-1a and AF-2 there was also a significant reduction of haze. In the case of nucieation agent with anti-fouling effect AF-3, on the basis of evaluation of 2 nd melting by DSC analysis it was determined that approximately 83 % of the total PP crystallised out in β-crystalline form. These results unambiguously indicate that there is no decomposition or change of structure of the nucieation agent through the reaction neither with triethylaluminium nor during polymerization (i.e., during the stay in the polymerization reactor). It is thus possible to assume that the original structure of the nucieation agent is recovered after the polymerization during the process of deactivation of the catalytic system by polar substances (typically H 2 0).

The presented results unambiguously showed that in comparison with commercially used anti-fouling agents, where the only purpose is the elimination of polymer powder fouling on the walls of the reactor, the presented invention makes it possible to resolve the problems associated with polymer powder fouling on the walls of a gas-phase reactor and also to prepare material with a very good dispersion of nucieation agent so that the polymer comes out of the reactor already well nucleated and displays better mechanical and optical properties after processing.

So the application of these substances into polymerization reactors has a positive influence on the operation of the gas-phase polymerization units and also allows the production of a polymer with a very well dispersed nucieation agent. Tab. 1 : Results of gas-phase polymerization of ethylene in 2-litre reactor.

Agent Agent Agent Agent Agent Yield Catalyst Activity Tr * Tr2* Tr2-Tr Agent MFR Density

Example

type amount /C 2 H4+N 2 +H 2 /TEA /Cat PE activity level bottom cover dif (120min) in PE 21.6 N PE mg mg/g g/g g/g g kg/<g*h) % °C °C °C wt% g/10min g/cm 3

Example 1.1 0 0.0 0.0 0.0 155 2.58 100 99.9 103.3 +3.4 0.00 5.5 966.2

Example 1.2 H 2 0 0.4 0.013 0.006 0.014 131 2.19 85 99.9 99.0 -0.9 0.00 5.2 965.8

Example 1.3 0 2 0.006 0.0002 0.0001 0.0002 74 1.24 48 99.9 99.2 -0.7 0.00 5.1 965.6

Example 1.4 NU-1 131 4.1 2.0 4.4 54 0.90 35 99.9 99.2 ■0.7 0.24 5.2 966.9

Example 1.7 AF-1a 130 4.0 2.0 4.3 118 1.97 77 99.9 99.1 -0.9 0.11 5.6 967.4

Example 1.8 AF-1 b 30 4.0 2.0 4.3 117 1.95 76 99.9 99.1 -0.8 0.11 5.8 967.4

Example 1.9 AF-1c 32 4.1 1.9 4.4 122 2.04 79 99.9 99.0 -0.9 0.11 5.9 967.5

Example 1.5 NU-2 68 2.1 1.0 2.3 110 1.84 71 99.9 99.0 -0.9 0.06 5.5 966.5

Example 1.10 AF-2 65 2.0 1.0 2.2 164 2.73 106 99.9 99.1 -0.7 0.04 6.0 967.4

Example 1.6 NU-3 132 4.1 2.0 4.4 90 1.50 58 99.9 99.3 -0.6 0.15 5.2 966.4

Example 1.11 AF-3 131 4.1 2.0 4.4 175 2.91 113 99.9 99.2 -0.7 0.08 6.1 966.9

* The temperatures Tr and Tr2 were recorded at 120 minutes of polymerization

Tab. 2: Results of gas-phase polymerization of propylene in 2-litre reactor.

Agent Agent Agent Agent Agent Yield Catalyst Activity Tr* Tr2* Tr2-Tr Agent MFR Crystal,

Example XS

type amount /C 3 H 6 /TEA /Cat PP activity level bottom cover dif (60min) in PP 21.6 N peak mg mg/g g/g g/g g kg/(g*h) % °C °C "C wt% g/10min wt% min

Example 2.1 0 0.0 0.0 0.0 150 25.0 100 75.0 77.8 +2.8 0.00 7.7 1.1 4.5

Example 2.2 Atmer 8 0.1 0.4 1.3 117 19.5 78 75.0 74.1 -0.9 0.01 6.2 1.0 5.1

Example 2.3 AF-1a 32 0.4 1.4 5.3 154 25.7 103 75.0 74.1 -0.9 0.02 8.6 1.1 2.9

Example 2.4 AF-1 b 31 0.4 1.4 5.2 151 25.1 100 75.0 74.1 -0.9 0.02 9.1 1.1 2.4

Example 2.5 AF-1 c 32 0.4 1.4 5.3 147 24.5 98 75.0 74.2 -0.8 0.02 8.9 1.0 2.8

Example 2.6 AF-1d 32 0.4 1.4 5.3 139 23.1 92 75.0 74.2 -0.8 0.02 8.4 1.2 3.0

Example 2.7 AF-2 142 1.9 6.2 23.7 152 25.4 102 75.0 74.0 -1.0 0.09 10.1 1.3 0.6

Example 2.8 AF-3 141 1.9 6.2 23.5 152 25.3 101 75.0 74.2 -0.8 0.09 10.0 1.1 0.7

* The temperatures Tr and Tr2 were recorded at 60 minutes of polymerization

Tab.3: Properties of PP prepared in 50-litre reactor.

Agent Agent MFR Crystal, β-phase Tensile Flexural

Example Haze

type in PP 21.6 N peak content modulus modulus wt% g/10min min % % MPa MPa

Example 3.1 - 0.00 7.3 4.8 0 38.1 ±1.1 1560 ±40 1610 ±20

Example 3.2 AF-1a 0.09 12.3 0.6 0 21.7 ±0.7 1980 ±30 1910 ±80

Example 3.3 AF-2 0.03 7.4 0.8 0 11.7 ±0.3 1930 ± 30 1740 ±20

Example 3.4 AF-3 0.03 5.7 0.9 83 34.6 ± 0.6 1810 ±50 1690 + 30