The present invention relates to a method of kinetic and static preparation of styrene polymers, in particular those intended for expanding and manufacturing of thermal insulation partitions with the required mechanical, geometrical and insulation parameters. The present invention relates also to styrene polymers so prepared. Polymers of styrene, in particular foamed (expanded), demonstrate very low resistance to heat streams of more than 85°C in which such polymers undergo physical and chemical degradation; this, through passage into the liquid phase and loss of thermal insulation properties, leads to their destruction.

Expanded polystyrene is a polymer material which is most frequently used in thermal insulation, e.g. in construction. It is characterized, inter alia, by a very low thermal conductivity index and low density. In order to enhance expanded polystyrene resistance to the effects of heat radiation and high temperature streams, organic and mineral flame retardants and their compositions are used as well as agents and compounds released as a result of thermal decomposition of the components.

A number of methods and preparations are known which reduce the flammability and enhance thermal resistance of expanded polystyrene with respect to its surface and weight but their effectiveness is insufficient. Additionally, in high temperature, well known and commonly applied preparations which reduce flammability and thermal resistance undergo pyrolysis thus causing pyrolysis of expanded polystyrene and, as a result, compounds are released which may cause, e.g. corrosion of metals being also catalysers of combustion processes.

Well known and commonly applied solutions concerning the preparation of polystyrene-based materials, which enhance their resistance to high temperature involve the application - as flame retardants - of compounds or compositions of compounds containing halides (e.g. HBCDD - hexabromocyclododecane). The above compounds or their simple compositions operate only in a temperature increased by their pyrolytic decomposition resulting in destruction, degradation or cracking of polystyrene the effect of which is its reduced flammability.

The published Canadian patent application CA2051774 presents an example of such a concept whereby a water solution which retards flames is applied, inter alia, for flame retardancy of polyolefins, and which contains: water soluble ammonium salt (ammonium phosphate or ammonium bromide), organic phosphates and stable binder for resins.

A similar concept is adopted in Canadian application CA2019325 which describes a composition enhancing flame retardancy of various materials (paper, cotton, wood, polymer materials). The preferred composition of the composition, described in the aforementioned invention, is ammonium bromide, boric acid, alcohol, surface-active agent and water. Auxiliary additions are chosen from amongst: sodium phosphate, monoammonium phosphate, diammonium phosphate, organic phosphate, phosphorus oxide, wood ash or metallic sodium.

Another concept type is the application - as flame retardant - of plastics or a halide-free composition containing monoammonium salts and/or various phosphorus compounds or phosphorus itself.

An example of such a concept is Japanese patent application JP92961 19 in which the inventors propose to combine a plastic, graphite (expanding in temperature) with red phosphorus and/or a phosphorus compound (in particular ammonium polyphosphate).

Applications US6444714 and US6420442 present the production of flame retarded polystyrene through polymerisation of styrene in the presence of a flame retardant which is a composition, in variable proportions, of expanded graphite with phosphorus compounds.

Another example of such a concept is application EP08141 19 in which flame resistant polystyrene is obtained through admixing a composition of metal hydroxide with phosphorus compounds. This group of materials also includes the plastic flame retardant described in application CA1201841 composed of: ammonium polyphosphate, ammonium monophosphate, anhydrous borax, borax, urea based amide, melamine. Other concepts are also known whereby the flame retardant composition includes ascorbic acid. Application KR20010096332 presents a composition based on a polyolefin polymer which uses natural compounds as anti-oxidants and/or flame resistant agents. Such a composition includes: polyolefin-based polymer resin, antioxidant (ascorbic acid or its derivatives, apple extract), a flame-resistant agent (lactic acid derivatives) and, additionally, an additive which reduces trickling, enhancing agent, plasticizer, compatibilizer, colouring agent, filler, antistatic agent, flame retardant, pigment, and/or dye.

In application CA2146034, inventors propose a stabilised composition with enhanced stability to thermal oxidation, which comprises polyolefins, ascorbic acid and one or more tocopherols.

Another concept of this type is application CA1251034 which presents a chemically active composition containing bivalent ferrous ions, ascorbic acid and/or citric acid and alum, where the ratio of ferrous (II) ion mass to ascorbic acid or citric acid is 1 : 0.02 and 0.30 (for ascorbic acid) or 1 : 0.01 and 0.80 (for citric acid).

A similar concept is presented in application CA2517460 which shows a flame retardant for polymers, textiles and wood, obtained from a ferrous compound (ferrous carbonate (II), ferrous hydroxide carbonate, ferrous hydroxide (II), ferric hydroxide (III), where the application of ascorbic acid is claimed as a flame retardant modifier.

Applications WO01 18120 and DE19828538, describe thermoplastic polycarbonate compact formed as a result of polymer grafting in the presence of ascorbic peracid, redox acidic initiator or ascorbic acid. In existing concepts, also "nano" substances are applied as ingredients of flame retarding compositions.

An example of such a concept is application CA2516292 which describes a flame retarding composition consisting of a polyolefin polymer, nanosilicates, metal hydroxide, calcium carbonate. A similar concept is provided in application CA2592281 which presents compact polystyrene foam containing multi-layer nanographite as an admixture enhancing the properties of the material. Having regard to the toxicity of the products of decomposition resulting from pyrolysis and thermal transformations of some of modifiers applied to date, e.g. as preparations reducing the flammability of polymer materials, it has become necessary to study the application of compounds whose decomposition products would be friendly to the natural environment and humans and which would, at the same time, meet the expectations from the production and modification of polystyrene.

The aim of the invention is to provide a method of neutralizing preparation of styrene polymers, especially intended for expanding, and, at the same time, reducing the presence in styrene polymers of flame retardants applied to date which, during pyrolysis and thermal transformations resulting in their decomposition, may be transformed into toxic products.

The aim of the invention is also to provide a prepared styrene polymer, especially intended for expanding, obtained according to the invention, during which energy centres generated by the polymer is neutralized, especially in the form of electrical friction charges with a known (+ or -) like sign which is an abhesive bridge for protective layers on the modified styrene polymer surface concerned.

The aim of the invention is primarily preparation of styrene polymer through electrostatic neutralisation, homogenisation and adhesive activation of the surface of styrene polymer, especially intended for expansion, and introduction of preparing agents into the monomer before polymerization or the introduction of such agents into the polymer after polymerization, and also, using thermoplastic properties of styrene polymer, introduction of preparing agents during its redrawing, pressing in higher temperature and pre-assumed pressure. The aim of the invention are thus prepared styrene polymers, especially ones intended for expansion and production of thermal insulation partitions, containing styrene polymers, organic porophores, and, optionally, surface active agents or, optionally, technological additions such as plasticizers, characterised in that they also contain organic and/or inorganic neutralizing preparation in solid or liquid form of between 5 g/kg and 200 g/kg in relation to the mass of polymer, preferably with an addition of ascorbic acid of between 0.5 g/kg and 170 g/kg and, optionally, they contain an addition in the form of organic auxiliary preparations in solid or liquid form of between 0.3 g/kg and 220 g/kg in relation to the mass of styrene polymer, preferably with an addition of ascorbic acid of between 1g/kg and 230 g/kg in relation to the mass of styrene polymer.

According to the invention, the neutralising preparation comprise ammonium bromide of between 0.1 and 18 parts by weight, and/or guanidine phosphate of between 0.1 and 19 parts by weight, monoammonium salt of sulphonic acid of between 0.1 and 15 parts by weight, and, optionally, ascorbic acid of between 0.1 and 17 parts by weight in relation to the styrene polymer.

The auxiliary preparation, preferably, according to the invention, is an acrylate- fluoroalkyl copolymer which contains dipropylene glycol ethyl ether.

Preferably, according to the invention, the quantity of the auxiliary preparation in the prepared polymer is between 0.1 and 16 parts by weight in relation to the styrene polymer.

Preferably, according to the invention, the quantity of ascorbic acid in the prepared polymer is between 0.05 - 9.5 parts by weight in relation to the styrene polymer. According to the invention, the proportions between the components of the neutralizing preparation vary.

Preferably, the neutralizing preparation is applied in solutions or water suspensions or in solid form; granulated, e.g.: in the form of powders with granularity of below 1500 pm. Preferably, the granularity of the neutralizing preparation used in the preparation of styrene polymers in solid form is within the range of 2-100 pm;

Preferably, the quantity of the auxiliary preparation applied in the form of a solution is between 0.3 g/kg and 220 g/kg in relation to the styrene polymer.

The aim of the invention is also a method of preparing styrene polymers, especially ones intended for expanding, whereby the neutralizing preparations and, optionally, the auxiliary preparations are introduced during one of the individual phases of obtaining styrene polymers, such as a) suspension polymerisation of the monomer; b) seasoning of the styrene polymer before expansion; c) preliminary expansion of the styrene polymer; d) drying and homogenization of the expanded styrene polymer; e) pneumatic transport of expanded styrene polymer to be block-formed; or, in the process of homogenization of the styrene polymer, through its extrusion, redrawing, pressing, characterised by that at the phase of suspension polymerisation of the monomer, the quantity of the neutralizing preparation introduced is between 0.1 and 18 parts by weight, with the neutralizing preparation in the dissolved form or in the form of a suspension, is introduced together with a typical water protective colloid at a temperature of 18 - 45°C; or, before the expansion of the styrene polymer, the quantity of the neutralizing preparation introduced is between 0.2 and 16 parts by weight, with the neutralizing preparation being introduced at ambient temperature in the form of dispersion by which the styrene polymer to be expanded is surrounded, and subsequently, all is mixed until the styrene polymer surface is fully coated; or, at the phase of preliminary expansion of the styrene polymer, the quantity of the neutralizing preparation introduced is between 0.1 and 16 parts by weight, with the neutralizing preparation being introduced in the form of water solution or suspension through spraying; or, at the phase of drying and homogenization of the expanded styrene polymer, the quantity of the neutralizing preparation is between 0.1 and 14 parts by weight, with the neutralizing preparation being introduced in the form of a water solution or dispersion; or, at the phase of pneumatic transport of the expanded styrene polymer, the quantity of the neutralizing preparation is between 0.1 and 14 parts by weight, with the neutralizing preparation being introduced in the form of water solution or granulated form before the expanded styrene polymer enters the block-forming chamber where styrene polymer blocks are formed in higher temperature and in the presence of steam; or, at the phase of extrusion, redrawing, pressing of the styrene polymer, the quantity of the neutralizing preparation is between 0.1 and 14 parts by weight; with the neutralizing preparation being introduced in granulated form.

According to the invention, at the phase of suspension polymerisation of the monomer, the neutralizing preparation in solid form, with the granularity of below 1500 pm or dissolved in water or in the form of a suspension of between 0.1 and 18 parts by weight is introduced directly into a known water protective colloid before the monomer is introduced or it is introduced directly into the monomer before it is introduced into the known water protective colloid.

According to the invention, before styrene polymer expansion, the neutralizing preparation in the form of a water solution or a suspension is introduced in the form of dispersion which is used to directly coat the styrene polymer surface during the mixing at a temperature of 10-35°C.

Preferably, according to the invention, at the phase of styrene polymer expansion, the neutralizing preparation in the form of a water solution or a suspension is introduced by spraying directly onto the expanded styrene polymer containing porophore.

According to the invention, at the phase of drying and homogenisation of the expanded styrene polymer, the neutralizing preparation is introduced in the form of dispersion by spraying onto the surface of the expanded polystyrene. According to the invention, at the phase of pneumatic transport of expanded styrene polymer, the neutralizing preparation is introduced in the form of dispersion and/or a solution by spraying onto the styrene polymer transported to the block-forming chamber. According to the invention, in the . process of homogenisation of the styrene polymer through its extrusion, redrawing, pressing, the neutralizing preparation is added in solid, granulated form. Preferably, according to the invention, the neutralizing preparation is applied in water solutions and/or in solid form.

Preferably, the granularity of the neutralizing preparation in solid form is within the range of 2-200 pm;

The neutralizing preparation in solid, granulated form, within the range of 2- 200 pm, is introduced into the pneumatic transport system using the difference between the pressure in the pneumatic transport duct (pipeline) and the pressure outside of the pipeline (injector principle). The neutralizing preparation is the agent which restricts the commencement of the burning of styrene polymer, and its addition makes it possible to considerably enhance the thermal resistance of expanded styrene polymer and restricts the transformation of expanded styrene polymer into the liquid phase (flowing, trickling).

According to the invention, at the phase of suspension polymerisation of the monomer, the auxiliary preparation is introduced together with the neutralizing preparation in form dissolved in water in the proportion of 3:10 to the typical protective colloid or in the form of water suspension of between 0.2 and 14 parts by weight in proportion to the typical protective colloid before the monomer is introduced.

According to the invention, before the styrene polymer is expanded, the auxiliary preparation together with the neutralizing preparation in total quantity between 0.2 and 16 parts by weight is introduced in the form of dispersion which is used to directly coat the styrene polymer surface during the mixing at a temperature of 36°C. According to the invention, at the phase of expanding the styrene polymer, the auxiliary preparation together with neutralizing preparation in total quantity between 0.1 and 16 parts by weight are introduced in the form of a water solution or dispersion by spraying onto the expanded styrene polymer.

According to the invention, at the phase of drying and homogenization of the expanded styrene polymer, the auxiliary preparation together with neutralizing preparation in total quantity between 0.1 and 14 parts by weight are introduced in the form of dispersion by spraying onto the surface of expanded styrene polymer.

According to the invention, at the phase of pneumatic transport of the expanded styrene polymer, the auxiliary preparation together with neutralizing preparation in total quantity between 0.1 and 14 parts by weight are introduced in the form of dispersion by spraying onto the styrene polymer transported to the block- forming chamber.

According to the invention, in the process of homogenisation of the styrene polymer through extrusion, redrawing, pressing, the neutralizing preparation together with the auxiliary preparation in total quantity between 0.1 and 14 parts by weight are added in solid granulated form.

The impact of the neutralizing preparation on styrene polymers consists in the use of the tension and current effects forming on the polymer surface (friction and electrolyte charges) and surface modification of the prepared polymer with like ions, through the diffusion of the ions on the area of excessive surface energy generated during the expansion, transport, especially pneumatic transport, technological seasoning and block-forming. Modification of styrene polymer in a mass, on the other hand, consists in introducing neutralizing preparations in the process of homogenization of the styrene polymer through its extrusion, redrawnig, pressing. Owing to the preparation of styrene. polymers according to the invention, energy streams are generated which offer the possibility to utilize "nano" effects with respect to the expanded polymer surface as a result of which the radicals and/or atoms produced are occluded on the dendritic surface of the expanded styrene polymer in elementary quantity particularly with respect to nitrogen in statu nascendi which leads to neutralisation of energy centres generated by the styrene polymer and the modifiers (neutralizing and auxiliary preparations) according to the invention. It was unexpectedly found, that an addition of ascorbic acid to the neutralizing preparation and/or the auxiliary preparation, in the form of water solution or in granulated form, has an effect on disturbing the oxygen index of expanded styrene polymers which results in considerable reduction of expanded polystyrene flammability reducing the effect of the polymer transferring into the liquid phase with low viscosity (so-called trickling).

Depending on the phase at which the neutralising preparation, optionally with the auxiliary preparation, is added to the styrene polymer, it is modified on its surface and/or throughout its volume (in its mass).

It was unexpectedly found, that a result of the preparation according to the invention may also be an improvement of thermal resistance (reduction in the lambda coefficient), mechanical parameters (resistance to compression, elasticity) and elastic recovery.

Furthermore, the application, in the method according to the invention of organic inserts of auxiliary preparations is an additional protection and compartment preventing the operation of external factors such as water, ultraviolet, ozone, finished expanded polystyrene elements in storage, transport and application on the construction site (assembly, gluing and fixing onto the required surfaces).

Unexpectedly, owing to the preparation of polystyrene according to the invention, the surfaces of expanded polystyrene beads were extended; after the block was cut through, the beads had very advantageous geometric properties characterised by an increased friction coefficient (grip) and the possibility to favourably store adhesive preparations (e.g. glues) limiting the generation of vacuums between the surface of e.g. the expanded polystyrene board and the protected plane (e.g. wall).

Preparation of styrene polymers, especially ones intended for expanding, with the method according to the invention, made it possible to reduce flammability and enhance the thermal resistance of expanded polystyrene as well as its resistance to the operation of ultraviolet, ozone and other adverse weather conditions and stabilised the effect on the basic expanded polystyrene parameters (lambda coefficient, compression, tightness).

The present invention is presented in more detail in the production examples which, however, do not restrict its scope; the preferable proportions between the ingredients of the neutralising preparation and the auxiliary preparation according to the invention, in parts by weight, are specified in the illustrative tables below:

Trade names of Parts by weight of the different ingredients

the auxiliary

preparation ingredients

FLUAL Nf 1 - 1 - 2 - 2 2.5 2.5

DICRYLAN AC ^® - 1 1 - - 2 - 2.5 2.5 ascorbic acid - - 0.5 0.5 - - 0.1 - 0.5

Water 0.5 0.6 0.5 - 0.5 0.5 - - -

The following are used in the neutralizing preparation, according to the invention:

- FLOVAN CWF® - is the trade name of the water solution produced by Huntsman Textile Effects with its seat in Germany, and its chemical composition is as follows:

a) guanidine phosphate of: 20-30 % by weight.

b) monoammonium salt of sulphonic acid of between 5 and 7.5 % by weight. Concentration of dry matter: 48.5 - 51 .5 %

and

- FLOVAN BU® is the trade name of the chemical produced by Huntsman Textile Effects with its seat in Germany, and its chemical composition is as follows:

Ammonium bromide of: 50-75 % by weight.

The following, used in the auxiliary preparation, according to the invention

- FLUAL Nl® is the trade name of the chemical produced by OLEA S.A. FRANCE with its seat in France, and its chemical composition is as follows:

ca. 15% solution of acrylate-fluoroalkyl copolymer which contains dipropylene glycol ethyl ether

and

- DICRYLAN AC® is the trade name of the chemical produced by Huntsman Textile Effects with its seat in Germany consisting of acrylic copolymer. The total quantity of the aforementioned chemicals, both in the neutralizing preparation and the auxiliary preparation in relation to the styrene polymer is between 5 g/kg and 200 g/kg. Example 1

Into a reactor filled with the well known water protective colloid applied in suspension polymerization, the neutralizing preparation in the form of water solution is introduced, and then styrene monomer is introduced and suspension polymerization following the well known method is performed. The monomer to neutralizing preparation ratio is 1 :10, and the composition of the neutralizing preparation is as follows: 100 parts by weight of FLOVAN CWF®, 50 parts by weight of FLOVAN BU® and 10 parts by weight of water. The exothermic process is performed at a temperature of between 20°C and 1 10°C, obtaining the prepared styrene polymer according to the invention.

Example 2

Into a reactor filled with the well known water protective colloid applied in suspension polymerization, the neutralizing preparation in the solid form with granulation of below 1500 μιη is introduced, and then, styrene monomer is introduced and suspension polymerization following the well known method is performed. The monomer to neutralizing preparation ratio is 10:0.6, and the composition of the neutralizing preparation is as follows: 0.1 parts by weight of FLOVAN CWF®, 0.3 parts by weight of FLOVAN BU®.

The exothermic process is performed at a temperature of between 20°C do 1 10°C, obtaining the prepared styrene polymer according to the invention.

Example 3

The following are introduced into a mixer:

100 parts by weight of styrene polymer intended for expanding and 10 parts by weight of the neutralizing preparation which contains: 6.3 parts by weight of FLOVAN CWF®, 0.6 parts by weight of ascorbic acid, 3.1 parts by weight of water and 0.1 parts by weight of the auxiliary preparation consisting of FLUVAL Nl®

Then, the mixer is set to motion with the rotational speed of 0.5 m/s for 10 minutes. After the mixer is emptied, the styrene polymer with prepared surface, intended for expanding with the well-known method is seasoned.

Example 4 In an expander provided with a mixing arm, during the expanding process - 100 parts by weight of polystyrene beads are dozed, 15 parts by weight of a solution of the neutralizing preparation are dozed by spraying, with the following composition: 5 parts by weight of FLOVAN CWF® 5 parts by weight of FLOVAN BU® and 5 parts by weight of water, and 0.1 parts by weight of the auxiliary preparation consisting of FLUVAL Nl®.

After the expanding process is completed, the material is dried at a temperature of 85-95°C, cooled to the ambient temperature and seasoned for 24 hours, and then, after a pre-determined homogenization period, all is transferred to the forming element where, after consolidation in the presence of steam, finished material is obtained, modified according to the invention, in the form of a expanded polystyrene block. Example 5

During pneumatic transport, before expanded and seasoned styrene polymer enters the block-forming chamber, dispersion of the neutralizing preparation and auxiliary preparation are placed on the polymer surface by spraying, as follows:

- for 100 parts by weight of preliminarily expanded polystyrene, 10 parts by weight of water solution of the neutralizing preparation consisting of: 5 parts by weight of FLOVAN CWF®; 2.5 parts by weight of FLOVAN BU®; 1 .5 parts by weight of ascorbic acid; 1 part by weight of water and 0.1 parts by weight of neutralizing preparation consisting of DICRYLAN AC®.

Then, the material is block-formed, where, after consolidation in the presence of steam at a temperature of 105°C, finished material is obtained according to the invention, in the form of an expanded polystyrene block. Example 6

The following are introduced into a mixer:

100 parts by weight of expended polystyrene and, by spraying, 6 parts by weight of neutralizing preparation in the form of powder with the granulation of 5 pm containing 6 parts by weight of FLOVAN CWF® and 1 part by weight of auxiliary preparation consisting of. a composition of 0.45 parts by weight of FLUVAL Nl ^® , 0.45 parts by weight of DICRYLAN AC ^® and 0.09 parts by weight of ascorbic acid are introduced. After mixing, all is transferred to a technological contained and then, after a certain period of homogenisation, transfer is made to the forming element where, after consolidation in the presence of steam, finished material is obtained, in the form of a expanded polystyrene block, modified according to the invention.

Example 7

Into a mixer filled with 100 parts by weight of styrene polymer in the form of beads intended for expanding, introduced are 5 parts by weight of FLOVAN BU ^® , 0.5 parts by weight of ascorbic acid, 0.3 parts by weight of technological additions reducing friction, in the form of magnesium stearate.

Then, all is homogenised in a redrawer (mixing screw) by heating up to plastic state over 2-10 minutes at a temperature of 120°C, using additional heat generated through deformation of polystyrene beads.

Thereafter, all is redrawered through a slot nozzle (screen), being mechanically fractioned at the nozzle mouth to the required diameters to obtain beads intended for expanding.

Owing to the preparation of styrene polymers according to the invention, the tightness of the material in block and geometric formats (after cutting) is improved, anisotropy of the medium is reduced, and enhanced are resistance parameters (bending, compressing, tearing), elasticity, shape memory, vibration and noise damping, resistance to depolymerisation in oxygen, ozone and ultraviolet radiation conditions, and stabilisation of lambda coefficient. Styrene polymers obtained following the method according to the invention are used, inter alia, for thermal insulation, in thermal insulation partitions, vibroacoustic and hydroinsulation compartments used in construction, means of transport, shields, packaging, insulation of pipelines, etc.