BACKGROUND OF THE INVENTION

The present invention relates to compositions which are useful as intermediates for dispersants used in lubricating oil compositions or as dispersants themselves. In addition, some of these compositions are useful in the preparation of novel high molecular weight dispersants which have superior dispersant properties for dispersing sludge and varnish and superior Viton Seal compatibility.

The high molecular weight dispersants of the present invention also advantageously impart fluidity modifying properties to lubricating oil compositions which are suffi- cient to allow elimination of some proportion of viscosity index improver from multigrade lubricating oil compositions which contain these dispersants.

Alkenyl-substituted succinic anhydrides have been used as dispersants. Such alkenyl-substituted succinic anhydrides have been prepared by two different processes, a thermal process (see, e.g., U.S. Patent No. 3,361,673) and a chlorination process (see, e.g., U.S. Patent No. 3,172,892). The polyisobutenyl succinic anhydride ("PIBSA") produced by the thermal process has been characterized as a monomer containing a double bond in the product. Although the exact structure of chlorination PIBSA has not been definitively determined, the chlorination process PIBAs have been charac- terized as monomers containing either a double bond, a ring, other than a succinic anhydride ring and/or chlorine in the product. [See J. Weill and B. Sillion, "Reaction of Chlorinated Polyisobutene with Maleic Anhydride-.Mechanism

Catalysis by Dichloromaleic Anhydride", Revue de l'lnstitut Frangais du Petrole, Vol. 40, No. 1, pp. 77-89 (January-February, 1985).] Such compositions include one-to-one monomeric adducts (see, e.g., U.S. Patents Noε. 3,219,666; 3,381,022) as well as adducts having poly- alkenyl-derived substituents adducted with at least 1.3 succinic groups per polyalkenyl-derived substituent (see, e.g., U.S. Patent No. 4,234,435).

In addition, copolymers of maleic anhydrides and some ali- phatic alpha-olefins have been prepared. The polymers so produced were useful for a variety of purposes including dispersants for pigments and intermediates in the prepara- tion of polyesters by their reaction with polyols or poly- epoxides. However, olefins having more than about 30 carbon atoms were found to be relatively unreactive. (See, e.g., U.S. Patents Nos. 3,461,108; 3,560,455; 3,560,456; 3,560,457; 3,580,893; 3,706,704; 3,729,450; and 3,729,451).

SUMMARY OF THE INVENTION

The present invention is directed to novel compositions useful ^" as additives which comprise copolymers of an unsatu- rated acidic reactant and high molecular weight olefin wherein at least about 20 percent of the total high molecular weight olefin comprises the alkylvinylidene isomer, said copolymers having alternating succinic and polyalkyl groups. The high molecular weight olefin has a sufficient number of carbon atoms such that the resulting copolymer is soluble in lubricating oil. Suitable olefins include those having about 32 carbon atoms or more (prefer- ably having about 52 carbon atoms or more). Those preferred high molecular weight olefins include polyisobutenes. Especially preferred are polyisobutenes having average

molecular weights of from about 500 to about 5000 and in which the alkylvinylidene isomer comprises at least 50 percent of the total olefin.

These copolymers are useful as dispersants themselves and also as intermediates in the preparation of other dispersant additives having improved dispersancy and/or detergency properties when employed in a lubricating oil.

These copolymers are also advantageous because they do not contain double bonds, rings, other than succinic anhydride rings, or chlorine (in contrast to thermal and chlorination PIBSAs) and as such have improved stability, as well as improved environmental properties due to the absence of chlorine.

The present invention is also directed to polysuccinimides which are prepared by reacting a copolymer of the present invention with a polyamine to give a polysuccinimide. The present invention is directed to mono-polysuccinimides (where a polyamine component reacts with one succinic group); bis-polysuccinimides (where a polyamine component reacts with a succinic group from each of two copolymer molecules, thus effectively cross-linking the copolymer molecules); and higher polysuccinimides (where a polyamine component reacts with a succinic group from each of greater than 2 copolymer molecules). These polysuccinimides are useful as dispersants arid/or detergents in fuels and oils. In addition, these polysuccinimides have advantageous vis- cosity modifying properties, and may provide a viscosity index credit ("V.I. Credit") when used in lubricating oils, which may permit elimination of some portion of viscosity index improver ("V.I. Improver") from multigrade lubricating oils containing the same.

In addition, the polysuccinimides of the present invention can form a ladder polymeric structure or a cross-linked polymeric structure. These structures are advantageous because it is believed such structures are more stable and resistant to hydrolytic degradation and also to degradation by shear stress.

In addition, the present invention is directed to modified polysuccinimides wherein one or more of the nitrogens of the polyamine component is substituted with a hydrocarbyl oxy- carbonyl, a hydroxyhydrocarbyl oxycarbonyl or a hydroxy poly(oxyalkylene)-oxycarbonyl. These modified polysuccini- mides are improved dispersants and/or detergents for use in fuels or oils.

Accordingly, the present invention also relates to a lubri- eating oil composition comprising a major amount of an oil of lubricating viscosity and an amount of a copolymer, polysuccinimide or modified succinimide additive of the present invention sufficient to provide dispersancy and/or detergency. The additives of the present invention may also be formulated in lubricating oil concentrates which comprise from about 90 to about 50 weight percent of an oil of lubri- eating viscosity and from about 10 to about 50 weight percent of an additive of the present invention.

Another composition aspect of the present invention is a fuel composition comprising a major portion of a fuel boiling in a gasoline or diesel range and an amount of copolymer, polysuccinimide or modified succinimide additives sufficient to provide dispersancy and/or detergency. The present invention is also directed to fuel concentrates comprising an inert stable oleophilic organic solvent boiling in the range of about 150°F to about 400°F and from

-_>

01 about 5 to about 50 weight percent of an additive of the

02 present invention.

03

04 Definitions

05

06 As used herein, the following terms have the following

07 meanings unless expressly stated to the contrary.

08

09 The term "unsaturated acidic reactants" refers to maleic or

10 fumaric reactants of the general formula: 11

12 0 0

^{X Λ} X-C-CH - CH-C-X' (II)

14

15 wherein X and X' are the same or different, provided that at

16 least one of X and X' is a group that is capable of reacting 7 to esterify alcohols, form amides or amine salts with ammo- 8 nia or amines, form metal salts with reactive metals or 9 basically reacting metal compounds and otherwise function as 0 acylating agents. Typically, X and/or X' is -OH, -O-hydro- 1 carbyl, -OM where M represents one equivalent of a metal, 2 ammonium or amine cation, - H-, -Cl, -Br, and taken together 3 X and X' can be -O- so as to form an anhydride. Preferably 4 X and X' are such that both carboxylic functions can enter 5 into acylation reactions. Maleic anhydride is a preferred unsaturated acidic reactant. Other suitable unsaturated 7 acidic reactants include electron-deficient olefins such as 8 monophenyl maleic anhydride; monomethyl, dimethyl, mono- 9 chloro, monobromo, monofluoro, dichloro and difluoro maleic 0 anhydride; N-phenyl maleimide and other substituted 1 maleimides; isomaleimides; fumaric acid, maleic acid, alkyl 2 hydrogen maleateε and fumarateε, dialkyl fumarates and 3 maleates, fumaronilic acids and maleanic acids; and 4 maleonitrile, and fumaronitrile.

The term "alkylvinylidene" or "alkylvinylidene isomer" refers to high molecular weight olefins and polyalkylene components having the following vinylidene structure

_| | 2 / \ ^{R R} v ^(III)

wherein R is alkyl or substituted alkyl of sufficient chain length to give the resulting molecule solubility in lubri¬ cating oils and fuels, thus R generally has at least about 30 carbon atoms, preferably at least about 50 carbon atoms and Rv is lower alkyl of about 1 to about 6 carbon atoms.

The term "soluble in lubricating oil" refers to the ability of a material to dissolve in aliphatic and aromatic hydro¬ carbons such as lubricating oils or fuels in essentially all proportions.

The term "high molecular weight olefins" refers to olefins (including polymerized olefins having a residual unsatura- tion) of sufficient molecular weight and chain length to lend solubility in lubricating oil to their reaction prod¬ ucts. Typically olefins having about 32 carbons or greater (preferably olefins having about 52 carbons or more) suffice.

The term "high molecular weight polyalkyl" refers to poly- alkyl groups of sufficient molecular weight and hydrocarbyl chain length that the products prepared having such groups are soluble in lubricating oil. Typically these high molecular weight polyalkyl groups have at least about 30 carbon atoms, preferably at least about 50 carbon atoms. These high molecular weight polyalkyl groups may be derived from high molecular weight olefins.

The term "PIBSA" is an abbreviation for polyisobutenyl succinic anhydride.

The term "polyPIBSA" refers to a class of copolymers within the scope of the present invention which are copolymers of polyisobutene and an unsaturated acidic reactant which have alternating succinic groups and polyisobutyl groups. PolyPIBSA has the general formula

wherein n is one or greater; R. , R,, ₃ and R. are selected fro hydrogen, methyl and polyisobutyl having at least about 30 carbo atoms (preferably at least about 50 carbon atoms) wherein either R. and R- are hydrogen and one of R, and * . is methyl and the other is polyisobutyl, or R, and R. are hydrogen and one of R., and R- is methyl and the other is polyisobutyl.

The term "PIBSA number" refers to the anhydride (succinic group) content of polyPIBSA on a 100% actives basis. The PIBSA number is calculated by dividing the saponification number by the percent polyPIBSA in the product. The units are mg KOH per gram sample.

The term " succinic group" refers to a group having the formula

I -CH-C-

I

-CH-C-Z ( IV ) || ° wherein W and Z are independently selected from the group consisting of -OH, -Cl, -O- lower alkyl or taken together are -0- to form a succinic anhydride group.

The term "degree of polymerization" expresses the length of a linear polymer and refers to the number of repeating (monomeric) units in the chain. The average molecular weight of a polymer is the product of the degree of polymer- ization and the average molecular weight of the repeating unit (monomer). Accordingly, the average degree of poly- merization is calculated by dividing the average molecular weight of the polymer by the average molecular weight of the repeating unit.

The term "polysuccinimide" refers to the reaction product of a copolymer of the present invention with polyamine.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 depicts one embodiment of a polysuccinimide of the present invention, wherein R is polyisobutyl, R- is lower alkyl, I is an initiator group and T is a terminator group.

°\ DETAILED DESCRIPTION OF THE INVENTION

A. COPOLYMER

The copolymers of the present invention are prepared by reacting a high molecular weight olefin wherein at least about 20% of the total olefin composition comprises the alkylvinylidene isomer and an unsaturated acidic reactant in the presence of a free radical initiator. Suitable high molecular weight olefins have a sufficient number of carbon atoms so that the resulting copolymer is soluble in lubricating oil and thus have on the order of about 32 carbon atoms or more. Preferred high molecular weight of olefins are polyisobutenes and polypropylenes. Especially preferred are polyisobutenes, particularly preferred are those having a molecular weight of about 500 to about 5000, more preferably about 900 to about 2500. Preferred unsaturated acidic reactants include maleic anhydride.

Since the high molecular weight olefins used to prepare the copolymers of the present invention are generally mixtures ^of individual molecules of different molecular weights, individual copolymer molecules resulting will generally contain a mixture of high molecular weight polyalkyl groups of varying molecular weight. Also, mixtures of copolymer molecules having different degrees of polymerization will be produced.

The copolymers of the present invention have an average degree of polymerization of 1 or greater, preferably from about 1.1 to about 20, and more preferably from about 1.5 to about 10.

/ 0 Among other, factors, the present invention is based on my surprising finding that the reaction of these high molecular weight olefins wherein at least about 20% of the total composition comprises the methylvinylidene isomer with an unsaturated acidic reactant in the presence of a free radical initiator results in a copolymer having alternating polyalkylene and succinic groups. This is surprising in view of the teachings that reaction of polyalkenes, such as polyisobutenes, with unsaturated acidic reactants such as maleic anhydride, in the presence of a free radical initiator, resulted in a product similar to that produced by the thermal process for PIBSA which is a monomeric one-to-one adduct (see, e.g., U.S. Patent No. 3,367,864). It was taught that high molecular weight olefins were rela- tive unreactive under those conditions which was confirmed by my findings that reaction of polyisobutene prepared using A1C1-. catalysis [in which the alkylvinylidene isomer com- prised a very small proportion (less than about 10%) of the total composition] with maleic anhydride in the presence of - free radical initiator resulted in low yield of product. In addition, the product obtained was similar to thermal PIBSA in molecular weight.

Thus, the copolymers of the present invention are prepared by reacting a "reactive" high molecular weight olefin in which a high proportion of unsaturation, at least about 20% is in the alkylvinylidene configuration, e.g.

CH- „2 / \

^{R R} „ ^v wherein R and R are as previously defined in conjunction with Formula III, with an unsaturated acidic reactant in the presence of a free radical initiator. The product copolymer

l i has alternating polyalkylene and succinic groups and has an average degree of polymerization of 1 or greater.

The copolymers of the present invention have the general formula:

wherein W and Z' are independently selected from the group consisting of -OH, -O- lower alkyl or taken together are -O- to form a succinic anhydride group, n is one or greater; and R. , ~, R, and R. are selected from hydrogen, lower alkyl of 1 to 6 carbon atoms, and high molecular weight polyalkyl wherein either R-, and R_ are hydrogen and one of R, and R, is lower alkyl and the other is high molecular weight poly¬ alkyl, or R, and R, are hydrogen and one of R. and R ₂ is lower alkyl and the other is high molecular weight polyalkyl.

In a preferred embodiment, when maleic anhydride is used as the unsaturated acidic reactant, the reaction produces copolymers predominately of the following formula:

/_e

wherein n is about 1 to about 100, preferably about 2 to about 20, more preferably 2 to 10, and R.,, R ₂ » R ₃ and R. are selected from hydrogen, lower alkyl of about 1 to 6 carbon atoms and higher molecular weight polyalkyl, wherein either R. and R- are hydrogen and one of R, and R. is lower alkyl and the other is high molecular weight polyalkyl or R, and R. are hydrogen and one of R- and R- is lower alkyl and the other is high molecular weight polyalkyl.

Preferably, the high molecular weight polyalkyl group has at least about 30 carbon atoms (preferably at least about 50 carbon atoms). Preferred high molecular weight polyalkyl groups include polyisobutyl groups. Preferred polyisobutyl groups include those having average molecular weights of about 500 to about 5000, more preferably from about 900 to about 2500. Preferred lower alkyl groups include methyl and ethyl; especially preferred lower alkyl groups include methyl.

Generally, such copolymers contain an initiator group, I, and a terminator group, T, as a result of the reaction with the free radical initiator used in the polymerization

\ 3

01 reaction. In such a case, the initiator and terminator

02 groups may be 03

0 0 0

04 I I I I

05 R- ₇ ", R ₇ 0-, R- -, R-.OCO-, R-.0C-0-, R _? -C-0-

06 ' 07 08 where R ₇ is hydrogen, alkyl, aryl, alkaryl, cycloalkyl, 09 alkoxy, cycloalkoxy, acyl, alkenyl, cycloalkenyl, alkynyl; 10 or alkyl, aryl or alkaryl optionally substituted with 1 to 11 4 substituents independently selected from nitrile, keto, 12 halogen, nitro, alkyl, aryl, and the like. Alternatively, 13 the initiator group and/or terminator group may be derived 14 from the reaction product of the initiator with another 15 material such as solvent; for example, the initiator may 16 react with toluene to produce a benzyl radical. 17

¹ ° The copolymers of the present invention differ from the ^■ * PIBSAs prepared by the thermal process in that the thermal

~ process products contain a double bond and a singly substi-

*f _

- ^• * ^■ tuted succinic anhydride group. The copolymers of the

²² present invention differ from the PIBSAs prepared by the

^* " chlorination process, since those products contain a double

²⁴ bond, a ring, other than a succinic anhydride ring or one or

² * ^> more chlorine atoms. 26

² ' The copolymers of the present invention contain no double ® bonds, rings, other than succinic anhydride rings, or * chlorine atoms. In addition, the succinic anhydride groups 0 are doubly substituted (i.e., have two substituents, one of 1 which may be hydrogen) at the 2- and 3-positions, that is: 2 3 4

A(l) High Molecular Weight Polyalkylene Group

The high molecular weight polyalkyl group is derived from a high molecular weight olefin. The high molecular weight olefins used in the preparation of the copolymers of the present invention are of sufficiently long chain length so that the resulting composition is soluble in and compatible with mineral oils, fuels and the like; and the alkylvinyl¬ idene isomer of the high molecular weight olefin comprises at least about 20% of the total olefin composition.

Such high molecular weight olefins are generally mixtures of molecules having different molecular weights and can have at least one branch per 6 carbon atoms along the chain, pre¬ ferably at least one branch per 4 carbon atoms along the chain, and particularly preferred that there be about one branch per 2 carbon atoms along the chain. These branched chain olefins may conveniently comprise polyalkenes prepared by the polymerization of olefins of from 3 to 6 carbon atoms, and preferably from olefins of from 3 to 4 carbon atoms, and more preferably from propylene or iεobutylene. The addition-polymerizable olefins employed are normally 1-olefins. The branch may be of from 1 to 4 carbon atoms, more uεually of from 1 to 2 carbon atoms and preferably methyl.

The preferred alkylvinylidene isomer comprises a methyl- or ethylvinylidene isomer, more preferably the methylvinylidene isomer.

The eεpecially preferred high molecular weight olefins used to prepare the copolymers of the present invention are poly- isobutenes which compriεe at leaεt about 20% of the more reactive methylvinylidene isomer, preferably at least 50% and more preferably at least 70%. Suitable polyisobutenes include those prepared using BF, catalysis. The preparation of such polyisobutenes in which the methylvinylidene isomer comprises a high percentage of the total composition is described in U.S. Patents Nos. 4,152,499 and 4,605,808.

Polyisobutenes produced by conventional AlCl, catalysis when reacted with unsaturated acidic reactants, such as maleic anhydride, in the preεence of a free radical initiator, produce products similar to thermal PIBSA in molecular weight and thus do not produce a copolymeric product.

Preferred are polyisobutenes having average molecular weights of about 500 to about 5000. Eεpecially preferred are those having average molecular weights of about 900 to about 2500.

A(2) Unsaturated Acidic Reactant

The unsaturated acidic reactant used in the preparation of the copolymers of the present invention comprises a maleic or fumaric reactant of the general formula:

0 0

X-C-CH = CH-C-X ¹

1 Lo

wherein X and X' are the εame or different, provided that at leaεt one of X and X' is a group that is capable of reacting to esterify alcohols, form amides or amine salts with ammo- nia or amines, form metal salts with reactive metals or basically reacting metal compounds and otherwise function to acylate. Typically, X and/or X' is -OH, -O-hydrocarbyl, -OM ⁺ where M represents one equivalent of a metal, ammonium or amine cation, -NH-, -Cl, -Br, and taken together X and X ^~ can be -0- so as to form an anhydride. Preferably, X and X' are such that both carboxylic functions can enter into acylation reactions. Preferred are acidic reactants where X and X' are each independently selected from the group con- sisting of -OH, -Cl, -0- lower alkyl and when taken together, X and X' are -0-. Maleic anhydride is the pre- ferred acidic reactant. Other suitable acidic reactants include electron-deficient olefins such as monophenyl maleic anhydride; monomethyl, dimethyl, monochloro, monobromo, monofluoro, dichloro and difluoro maleic anhydride; N-phenyl maleimide and other substituted maleimides; isomaleimides; fumaric acid, maleic acid, alkyl hydrogen maleates and fumarates, dialkyl fumarates and maleates, fumaronilic acids and maleanic acids; and maleonitrile, and fumaronitrile.

Preferred unsaturated acidic reactants include maleic anhydride, and maleic acid. The particularly preferred acidic reactant is maleic anhydride.

A(3) General Preparation of Copolymer

As noted above, the copolymers of the preεent invention are prepared fay reacting a reactive high molecular weight olefin and an unεaturated acidic reactant in the preεence of a free radical initiator.

ι7

The reaction may be conducted at a temperature of about -30 ^β C to about 210°C, preferably from about 40°C to about 150°C. I have found that degree of polymerization is inversely proportional to temperature. Accordingly, for the preferred high molecular weight copolymerε, it iε advan- tageous to employ lower reaction temperatures. For example, if the reaction is conducted at about 138 ^β C, an average degree of polymerization of about 1.3 was obtained. How- ever, if the reaction was conducted at a temperature of about 40°C, an average degree of polymerization of about 10.5 was obtained.

The reaction may be conducted neat, that is, both the high molecular weight olefin, and acidic reactant and the free radical initiator are combined in the proper ratio, and then stirred at the reaction temperature.

Alternatively, the reaction may be conducted in a diluent. For example, the reactantε may be combined in a solvent. Suitable solvents include those in which the reactants and free radical initiator are soluble and include acetone, tetrahydrofuran, chloroform, methylene chloride, dichloro- ethane, toluene, dioxane, chlorobenzene, xylenes, or the like. After the reaction iε complete, volatile components may be stripped off. When a diluent is employed, it iε preferably inert to the reactantε and productε formed and is generally used in an amount sufficient to ensure efficient stirring.

Moreover, my colleague W. R. Ruhe, has discovered that in the preparation of polyPIBSA, improved resultε are obtained by using PIBSA or polyPIBSA as a solvent for the reaction. (See, e.g., Examples 16, 17A and 17B herein.)

In general, the copolymerization can be initiated by any free radical initiator. Such initiators are well known in the art. However, the choice of free radical initiator may be influenced by the reaction temperature employed.

The preferred free-radical initiators are the peroxide-type polymerization initiators and the azo-type polymerization initiatorε. Radiation can alεo be used to initiate the reaction, if desired.

The peroxide-type free-radical initiator can be organic or inorganic, the organic having the general formula: R,OOR,' where R-, is any organic radical and R,' is selected from the group consiεting of hydrogen and any organic radical. Both R, and R,' can be organic radicals, preferably hydrocarbon, aroyl, and acyl radicals, carrying, if desired, subεtituentε εuch aε halogens, etc. Preferred peroxides include di-tert-butyl peroxide, tert-butyl peroxybenzoate, and dicumyl peroxide.

Examples of other suitable peroxides, which in no way are limiting, include benzoyl peroxide; lauroyl peroxide; other tertiary butyl peroxides; 2,4-dichlorobenzoyl peroxide; tertiary butyl hydroperoxide; cumene hydroperoxide; diacetyl peroxide; acetyl hydroperoxide; diethylperoxycarbonate; tertiary butyl perbenzoate; and the like.

The azo-type compounds, typified by alpha,alpha'-azo- bisisobutyronitrile., are alεo well-known free-radical promoting materialε. Theεe azo compounds can be defined as those having present in the molecule group -N-=N wherein the balances are satisfied by organic radicals, at least one of which is preferably attached to a tertiary carbon. Other suitable azo compounds include, but are not limited to,

I * .

p-bromobenzenediazonium fluoborate; p-tolyldiazoaminoben- zene; p-bromobenzenediazonium hydroxide; azomethane and phenyldiazonium halides. A εuitable liεt of azo-type com- poundε can be found in U.S. Patent No. 2,551,813, issued May 8, 1951 to Paul Pinkney.

The amount of initiator to employ, exclusive of radiation, of course, depends to a large extent on the particular initiator chose, the high molecular olefin used and the reaction conditionε. The initiator muεt, of courεe, be εoluble in the reaction medium. The uεual concentrationε of initiator are between 0.001:1 and 0.2:1 moles of initiator per mole of acidic reactant, with preferred amounts between 0..005:1 and 0.10:1.

The polymerization temperature must be sufficiently high to break down the initiator to produce the deεired free-radi- calε. For example, uεing benzoyl peroxide as the initiator, the reaction temperature can be between about 75°C and about 90°C, preferably between about 80 ^β C and about 85°C. Higher and lower temperatures can be employed, a suitable broad range of temperatures being between about 20°C and about 200°C, with preferred temperatures between about 50°C and about 150°C.

The reaction presεure εhould be εufficient to maintain the εolvent in the liquid phase. Pressures can therefore vary between about atmospheric and 100 psig or higher, but the preferred presεure iε atmoεpheric.

The reaction time iε uεually εufficient to reεult in the εubstantially complete conversion of the acidic reactant and high molecular weight olefin to copolymer. The reaction

time is suitable between one and 24 hours, with preferred reaction times between two and ten hours.

Aε noted above, the subject reaction is a εolution-type polymerization reaction. The high molecular weight olefin, acidic reactant, solvent and initiator can be brought together in any suitable manner. The important factors are intimate contact of the high molecular weight olefin and acidic reactant in the presence of a free-radical producing material. The reaction, for example, can be conducted in a batch system where the high molecular weight olefin is added all initially to a mixture of acidic reactant, initiator and solvent or the high molecular weight olefin can be added intermittently or continuously to the reaction pot. Alter- natively, the reactants may be combined in other orders; for example, acidic reactant and initiator may be added to high molecular weight olefin and solvent in the reaction pot. In another manner, the componentε in the reaction mixture can be added continuouεly to a εtirred reactor with continuouε removal of a portion of the product to a recovery train or to other reactorε in series. The reaction can alεo εuit- ably take place in a coil-type reactor where the componentε are added at one or more pointε along the coil.

In one enviεioned embodiment, the reaction product of an unεaturated acidic reactant and a high molecular weight, high vinylidene-containing olefin iε further reacted thermally. In this embodiment, any unreacted olefin, generally the more hindered olefins, i.e., the non-vinyl- idene, that do not react readily with the unεaturated acidic reactant under free radical conditions are reacted with unεaturated acidic reactant under thermal conditionε, i.e., at temperatureε of about 180° to 280°C. Theεe conditions

are similar, to those uεed for preparing thermal proceεs PIBSA.

The reaction solvent, as noted above, must be one which dissolves both the acidic reactant and the high molecular weight olefin. It is necessary to dissolve the acidic reactant and high molecular weight olefin so as to bring them into intimate contact in the solution polymerization reaction. It haε been found that the solvent must also be one in which the resultant copolymers are soluble.

Suitable soiventε include liquid εaturated or aromatic hydrocarbonε having from six to 20 carbon atoms; ketones having from three to five carbon atomε; and liquid εaturated aliphatic dihalogenated hydrocarbonε having from one to five carbon atoms per molecule, preferably from one to three car- bon atoms per molecule. By "liquid" is meant liquid under the conditions of polymerization. In the dihalogenated hydrocarbons, the halogens are preferably on adjacent carbon atoms. By "halogen" is meant F, Cl and Br. The amount of solvent must be such that it can dissolve the acidic reac- tant and high molecular weight olefin in addition to the resulting copolymers. The volume ratio of solvent to high molecular weight olefin is suitably between 1:1 and 100:1 and iε preferably between 1.5:1 and 4:1.

Suitable εolventε include the ketones having from three to six carbon atoms and the saturated dichlorinated hydro- carbons having from one to five, more preferably one to three, carbon atoms.

Examples of suitable solvents include, but are not limited ' to:

_- ^**" )-3->

1. ketones, such as: acetone; methylethylketone; diethylketonej and methyliεobutylketone;

2. aromatic hydrocarbonε,εuch aε: benzene; xylene; and toluene;

3. εaturated dihalogenated hydrocarbonε, εuch aε: dichloromethane; dibromomethane; l-bromo-2-chloroethane; 1,1-dibromoethane; 1,1-dichloroethane; 1,2-dichloroethane; 1,3-dibromopropane; 1,2-dibromopropane; l,2-dibromo-2-methylpropane; 1,2-dichloropropane; 1,1-dichloropropane; 1,3-dichloropropane; l-bromo-2-chloropropane; 1,2-dichlorobutane; 1,5-dibromopentane; and 1,5-dichloropentane; or

4. mixtureε of the above, εuch aε: benzene- methylethylketone.

As noted previously, W. R. Ruhe has discovered that use of a mixture of copolymer and polyisobutene aε a εolvent results in improved yields and advantageously disεolves the acidic reactant when used as a reaction medium.

The copolymer is conveniently separated from εolvent and unreacted acidic reactant by conventional procedureε such as phase separation, solvent distillation, precipitation and the like. If desired, dispersing agents and/or cosolvents may be used during the reaction.

The isolated copolymer may then be reacted with a polyamine to form a polymeric succinimide. The preparation and

characterization of εuch polysuccinimides and their treat- ment with other agents to give other dispersant compositions is described herein.

A(4) Preferred Copolymers

Preferred copolymers include those where an unsaturated acidic reactant, most preferably maleic anhydride, is copolymerized with a "reactive" polyisobutene, in which at least about 50 percent or more of the polyisobutene com- priseε the alkylvinylidene, more preferably, the methyl- vinylidene, isomer, to give a "polyPIBSA".

Preferred are polyPIBSAs wherein the polyisobutyl group has an average molecular weight of about 500 to about 5000, more preferably from about 950 to about 2500. Preferred are polyPIBSAs having an average degree of polymerization of about 1.1 to about 20, more preferably from about 1.5 to about 10.

B. POLYSUCCINIMIDES

The polyamino polysuccinimides of the present invention are prepared by reacting a copolymer of the present invention with a polyamine. Polysuccinimides which may be prepared include monopolysuccinimides (where a polyamine component reacts with one εuccinic group), bis-polysuccinimideε (where a polyamine component reacts with a εuccinic group from each of two copolymer molecules), higher succinimides (where a polyamine component reactε with a εuccinic group from each of more than 2 copolymer moleculeε) or mixtures thereof. The polysuccinimide(ε) produced may depend on the charge mole ratio of polyamine to εuccinic groups in the copolymer molecule and the particular polyamine used. Using a charge

mole ratio of polyamine to succinic groups in copolymer of about 1.0, predominately monopolysuccinimide iε obtained. Charge mole ratioε of polyamine to succinic group in copoly- mer of about 1:2 may produce predominately bis-polysucci- nimide. Higher polyεuccinimides may be produced if there is branching in the polyamine so that it may react with a succinic group from each of greater than 2 copolymer molecules.

B(l) Preferred Copolymers

Preferred copolymers include polyPIBSAs prepared according to the preεent invention as deεcribed hereinabove.

Preferred polyPIBSAs include those prepared using a poly- isobutene of average molecular weight of about 500 to about 5000, preferably of about 950 to about 2500 and wherein at least about 50 percent of the total polyisobutene comprises the alkylvinylidene isomer. Preferred alkylvinylidene isomers include methylvinylidene and ethylvinylidene. Especially preferred is methylvinylidene. Preferred are polyPIBSAs having an average degree of polymerization of about 1.1 to about 15. Particularly preferred polyPIBSAs have an average degree of polymerization of about 1.5 to about 10, and which are prepared uεing a polyiεobutene having an average molecular weight of about 900 to about 2500.

B(2) Polyamine

The polyamine employed to prepare the polyamino poly- succinimides iε preferably polyamine having from 2 to about 12 amine nitrogen atoms and from 2 to about 40 carbon atoms. The polyamine iε reacted with polyPIBSA to produce the poly-

amino polysuccinimide, employed in this invention. The polyamine is so selected so as to provide at least one basic amine per succinimide group. Since the reaction of a nitrogen of a polyamino polysuccinimide to form a hydro- carbyl oxycarbonyl, a hydroxy hydrocarbyl oxycarbonyl or a hydroxy polyoxyalkylene oxycarbonyl is believed to effi- ciently proceed through a secondary or primary amine, at least one of the basic amine atoms of the polyamino poly- succinimide must either be a primary amine or a secondary amine. Accordingly, in those instances in which the succinimide group contains only one basic amine, that amine muεt either be a primary amine or a εecondary amine. The polyamine preferably has a carbon-to-nitrogen ratio of from about 1:1 to about 10:1.

The polyamine portion of the polyamino polysuccinimide may be substituted with substituents selected from (a) hydrogen, (b) hydrocarbyl groupε of from 1 to about 10 carbon atomε, (c) acyl groups of from 2 to about 10 carbon atoms, and (d) monoketo, monohydroxy, mononitro, monocyano, lower alkyl and lower alkoxy derivatives of (b) and (c). "Lower", as used in terms like "lower alkyl" or "lower alkoxy", means a group containing from 1 to about 6 carbon atoms. At least one of the subεtituentε on one of the amineε of the polyamine is hydrogen, e.g., at least one of the basic nitrogen atoms of the polyamine is a primary or εecondary amino nitrogen atom.

Hydrocarbyl, as used in describing the polyamine components of this invention, denotes an organic radical composed of carbon and hydrogen which may be aliphatic, alicyclic, aromatic or combinations thereof, e.g., aralkyl. Prefer- ably, the hydrocarbyl group will be relatively free of aliphatic unεaturation, i.e., ethylenic and acetylenic,

_

particularly acetylenic unsaturation. The εubstituted polyamines of the present invention are generally, but not necesεarily, N-εubεtituted polyamineε. Exemplary hydro- carbyl groups and εubεtituted hydrocarbyl groupε include alkylε εuch aε methyl, ethyl, propyl, butyl, iεobutyl, pentyl, hexyl, octyl, etc., alkenylε εuch aε propenyl, isobutenyl, hexenyl, octenyl, etc., hydroxyalkyls, εuch aε 2-hydroxyethyl, 3-hydroxypropyl, hydroxyisopropyl, 4-hydroxybutyl, etc. ketoalkyls, εuch aε 2-ketopropyl, 6-ketooctyl, etc., alkoxy and lower alkenoxy alkylε, εuch aε ethoxyethyl, ethoxypropyl, propoxyethyl, propoxypropyl, 2-(2-ethoxyethoxy)ethyl, 2-(2-(2-ethoxy-ethoxy)ethoxy)ethyl, 3,6,9,12-tetraoxatetradecyl, 2-(2-ethoxyethoxy)hexyl, etc. The acyl groupε of the aforementioned (c) εubstituentε are εuch aε propionyl, acetyl, etc. The more preferred εubεtit- uents are hydrogen, C,-Cg alkyls and _^ -Cg hydroxyalkylε.

In a εubεtituted polyamine the εubstituents are found at any atom capable of receiving them. The subεtituted atomε, e.g., εubεtituted nitrogen atoms, are generally geometri- cally inequivalent, and consequently the substituted amines finding use in the present invention can be mixtures of mono- and polysubstituted polyamines with substituent groups situated at equivalent and/or inequivalent atoms.

The more preferred polyamine finding use within the scope of the present invention is a polyalkylene polyamine, including alkylene diamine, and including subεtituted polyamineε, e.g., alkyl substituted polyalkylene polyamine. Preferably, the alkylene group contains from 2 to 6 carbon atoms, there being preferably from 2 to 3 carbon atoms between the nitrogen atoms. Such groups are exemplified by ethylene, 1,2-propylene, 2,2-dimethylpropylene, trimethylene, etc. Examples of such polyamines include ethylene diamine,

*. ?

diethylene triamine, di(trimethylene)triamine, dipropylene triamine, triethylene tetramine, tripropylene tetramine, tetraethylene pentamine, and pentaethylene hexamine. Such amines encompass isomers such as branched-chain polyamine and the previouεly mentioned substituted polyamines, including hydrocarbyl-subεtituted polyamineε. Among the polyalkylene polyamineε, those containing 2-12 amine nitrogen atoms and 2-24 carbon atoms are especially preferred, and the - ₂ -C _ς alkylene polyamines are most preferred, in particular, the lower polyalkylene polyamines, e.g., ethylene diamine, dipropylene triamine, etc.

Preferred polyamines alεo include heavy polyamines such as polyamine HPA available from Union Carbide.

The polyamine component also may contain heterocyclic poly- amineε, heterocyclic εubεtituted amines and subεtituted heterocyclic compoundε, wherein the heterocycle comprises one or more 5 to 6-membered rings containing oxygen and/or nitrogen. Such heterocycles may be εaturated or unsaturated and subεtituted with groups selected from the aforementioned (a), (b), (c) and (d). The heterocycles are exemplified by piperazines, εuch aε 2-methylpiperazine, N-(2-hydroxyethyl)- piperazine, 1,2-biε-(n-piperazinyl)ethane, and N,N'-biε(N- piperazinyl)piperazine, 2-methylimidazoline, 3-amino- piperidine, 2-aminopyridine, 2-(3-aminoethyl)-3-pyrroline, 3-aminopyrrolidine, N-(3-aminopropyl)-morpholine, etc. Among the heterocyclic compounds, the piperazines are preferred.

Typical polyamines that can be used to form the compounds of this invention include the following:

0/03359

ethylene diamine, 1,2-propylene diamine, 1,3-propylene diamine, diethylene triamine, triethylene tetramine, hexamethylene diamine, tetraethylene pentamine, methyl- aminopropylene diamine, N-(betaaminoethylJpiperazine, N,N'-di(betaaminoethyl)piperazine, N,N'-di(beta-amino- ethyl)-imidazolidone-2, N-(beta-cyanoethyl)ethane-l,2- diamine, 1,3,6,9-tetraaminooctadecane, l,3,6-triamino-9- oxadecane, N-(beta-aminoethyl)diethanolamine, N-methyl-1,2- propanediamine, 2-(2-aminoethylamino)-ethanol,2-[2-(2-amino- ethylamino)ethylamino]-ethanol.

Another group of suitable polyamines are the propylene- amines, (bisaminopropylethylenediamines) . Propyleneamines are prepared by the reaction of acrylonitrile with an ethyleneamine, for example, an ethyleneamine having the formula H ₂ N(CH ₂ CH ₂ NH) .H wherein . is an integer from 1 to 5, followed by hydrogenation of the resultant intermediate. Thus, the product prepared from ethylene diamine and acrylonitrile would be H.,N(CH ₂ ) ₃ NH(CH ₂ ) ₂ NH(CH ₂ )-NH ₂ .

In many instanceε the polyamine used as a reactant in the production of polysuccinimides of the present invention iε not a sin-gle compound but a mixture in which one or several compounds predominate with the average composition indi- cated. For example, tetraethylene pentamine prepared by the polymerization of aziridine or the reaction of dichloro- ethylene and ammonia will have both lower and higher amine members, e.g., triethylene tetramine, subεtituted piperazineε and pentaethylene hexamine, but the composition will be largely tetraethylene pentamine and the empirical formula of the total amine composition will closely approximate that of tetraethylene pentamine. Finally, in preparing the polysuccinimide for use in this invention, where the various nitrogen atoms of the polyamine are not

al geometrically equivalent, several subεtitutional iεomerε are poεsible and are encompassed within the final product. Methods of preparation of polyamines and their reactions are detailed in Sidgewick'ε "The Organic Chemiεtry of Nitrogen", Clarendon Preεε, Oxford, 1966; Noller'ε "Chemistry of Organic Compounds", Saunders, Philadelphia, 2nd Ed., 1957; and Kirk-Othmer's "Encyclopedia of Chemical Technology", 2nd Ed., especially Volume 2, pp. 99-116.

B(3) General Preparation

The polysuccinimides are prepared by reacting copolymer with a polyamine to form a mono-, bis-polyεuccinimide, higher polysuccinimide or mixtures thereof. The charge mole ratio of polyamine to succinic groups in copolymer may determine the mixture of polysuccinimideε formed. For example, a product compriεing mono-, biε-polyεuccinimide or higher polysuccinimide can be prepared by controlling the molar ratios of the polyamine and succinic groups in copolymer and the polyamine used. Thus, if about one mole of polyamine is reacted with one mole of succinic group in the copolymer, a predominately mono-polysuccinimide product will be prepared. If about two moles of succinic group in the copolymer are reacted per mole of polyamine, a bis-polysuccinimide may be prepared. If higher amountε of εuccinic group in copolymer are uεed, higher polyεuccinimideε may be prepared provided that there are sufficient basic amino groups (or sufficient branching) in the polyamine to react with a succinic group from each of several copolymer molecules to produce the higher polysuccinimide. Due to the croεε-linking of copolymer moleculeε by the polyamine component, compoεitions of very high molecular weight, on the order of about 10,000 to about 100,000 may be prepared.

36

The reaction of a polyamine with an alkenyl or alkyl εuccinic anhydride to produce the polyamino alkenyl or alkyl succinimides is well known in the art and is disclosed in U.S. Patents Noε. 2,992,708; 3,018,291; 3,024,237; 3,100,673; 3,219,666; 3,172,892; and 3,272,746. The above are incorporated herein by reference for their diεclosures of preparing alkenyl or alkyl succinimideε. The preεent polysuccinimides may be prepared by following the general procedures described therein.

Accordingly, polyamine and copolymer are contacted at the desired molar ratio to give the desired mono-, bispoly- succinimideε or higher polyεuccinimides or mixtures thereof. The reaction may be carried out neat or preferably in solution. Suitable solvents include organic solvents, including alcohols, aliphatic and aromatic solvents, and the like. The reaction is conducted at a temperature of about 80°C to about 250°C, preferably from about 120 ^β C to about 180°C and is generally complete within about 2 to about 24 hours. The reaction may be conducted under ambient presεure and atmospheric conditions, although a nitrogen atmosphere at atmoεpheric preεεure may be preferred. The deεired product may be isolated by conventional procedureε, εuch as water wash and stripping, usually with the aid of vacuum, of any residual solvent.

B(4) General Preparation of Preferred Polysuccinimides

The preferred polysuccinimideε of the present invention are prepared by reacting a polyPIBSA copolymer of the present invention with polyamine. The charge mole ratio of polyamine to εuccinic groupε in the polyPIBSA will effect whether monopolyεuccinimideε, bis-polysuccinimideε, or higher polysuccinimides or mixtures thereof are produced

-31

and/or predominate. Accordingly, with a charge mole ratio (CMR) of about one mole of polyamine per mole of succinic groups in the polyPIBSA primarily mono-polysuccinimide will be formed. However, at a CMR of 0.5 mole polyamine per mole of succinic group in the polyPIBSA, there is a tendency to form bis-polyεuccinimides where the polyamine component acts to link two εuccinic groupε, thuεly forming a croεs-linked composition. Accordingly, the reaction of polyPIBSA and polyamine will yield a mixture of products which I term "polysuccinimides" and which term includes monopolysuccini- mides, also higher succinimides and bis-polysuccinimideε and compositions of intermediate structure.

The reaction is carried out by contacting polyamine and polyPIBSA. Although the ratio of the reactants is not critical, aε noted above a CMR may be chosen so as to yield desired polyεuccinimide proportions. The reaction is carried out at a temperature sufficient to cause reaction of the polyamine with a succinic group of the polyPIBSA. In particular, reaction temperatures from about 120°C to about 180°C are preferred, with temperatures from about 140°C to about 170°C being especially preferred.

The reaction may be conducted neat - that is both the polyamine and the polyPIBSA are combined and then stirred at the reaction temperature.

Alternatively, the reaction may be conducted in a diluent. For example, the reactants may be combined in a εolvent such as aliphatic or aromatic solvents, and the like, and then stirred at the reaction temperature. After completion of the reaction, volatile components may be stripped off. When

0/03359

a diluent is employed, it is preferably inert to the reac- tants and products formed and is generally used in an amount sufficient to ensure efficient stirring.

Preferred are polyamineε having from about 2 to about 12 amine nitrogen atoms and from about 2 to about 40 carbon atoms. The more preferred polyamineε employed in this reaction are generally repreεented by the formula:

wherein Y iε an alkylene group of 2 to 10 carbon atoms, preferably from 2 to 6 carbon atoms, and a is an integer from about 1 to 11, preferably from 1 to 6. However, the preparation of these alkylene polyamines does not produce a εingle compound and cyclic heterocycleε, such aε piperazine, may be included to εome extent in the alkylene diamines.

B(5) Preferred Polysuccinimides

(a) Monopolysuccinimideε

Preferred monopolyεuccinimideε include thoεe having the following formula:

^

wherein Am iε a linking group having from about 0 to about 10 amine nitrogen atomε and from about 2 to about 40 carbon atoms; n is 1 or greater and R., R ₂ , R, and R, are selected from hydrogen lower alkyl of 1 to 6 carbon atoms; and high molecular weight polyalkyl; wherein either R- and R ₂ are hydrogen and one of R- and R, is lower alkyl and the other is high molecular weight polyalkyl or R, and R . are hydrogen and one of R, and R- is lower alkyl and the other is high molecular weight polyalkyl; and R-. and R _g are independently hydrogen, lower alkyl of 1 to 6 carbon atoms, phenyl or taken together are alkylene of 3 to 6 carbon atoms to give a ring.

Preferred high molecular weight polyalkyl groups include polyisobutyl groups having at leaεt about 30 carbon atomε, more preferably, at leaεt about 50 carbon atomε. Eεpecially preferred are polyiεobutyl groupε having an average molecular weight of about 500 to about 5000, more preferably from about 900 to about 2500.

^j - Y

Preferred lower alkyl groupε include methyl and ethyl. Eεpecially preferred are compoundε where the lower alkyl group iε methyl.

Preferred are compoundε where R _ς and R _g are hydrogen or methyl; preferred R _ς and R _g groupε include hydrogen.

Preferred are Am groupε having from about 0 to about 10 amine nitrogen atomε and from about 2 to about 40 carbon atomε. More preferred are Am groups of the formula -[ (ZNH) )Z' ]- wherein Z and Z' are independently alkylene of from about 2 to about 6 carbon atoms and p is an integer from 1 to 6. Especially preferred are Am groups where Z and Z ^r are ethylene and p iε 2, 3 or 4.

Preferred are compoundε where n iε from about 2 to about 20, more preferably from about 2 to about 10.

Preferred are compounds having an average degree of polymer- ization of from about 1.1 to about 20, more preferably from about 1.5 to about 10.

(b) Bis-polysuccinimideε

Preferred polyεuccinimideε include thoεe which partially compriεe at leaεt in part a bis-polysuccinimide structure. Some of these preferred polysuccinimideε are random poly- succinimides which comprise units selected from:

B

wherein Am iε a linking group having from about 0 to 10 amine nitrogen atomε and from about 2 to 40 carbon atoms;

1' 2' 3' 4' 1 ' ' ' 3 ' 4 ' 1 ' 2 ' 3 ' an . are selected from hydrogen, lower alkyl of one to 6 carbon atoms and high molecular weight polyalkyl; wherein either R. and R ₂ are hydrogen and one of R _g and R . iε lower alkyl and the other iε polyalkyl, or R, and R. are hydrogen and one of

R. and R-, iε lower alkyl and the other iε polyalkyl; either

R. ' and R ₂ ' are hydrogen and one of R,' and R.' iε lower alkyl and the other is polyalkyl, or R,' and R.' are hydrogen and one of R- ' and R ₂ ' is lower alkyl and the other is polyalkyl; and either R«" and R-" are hydrogen and one of

R," and R." is lower alkyl and the other is polyalkyl or R-" and R." are hydrogen and one of R," and R ₂ " is lower alkyl and the other iε polyalkyl and R- and R _g are independently hydrogen, lower alkyl of 1 to 6 carbon atomε, phenyl or taken together are alkylene of 3 to 6 carbon atoms to give a ring; a, a', b and b' are sites for a covalent bond provided that at least one a or a' site of each unit is covalently bonded to a b or b' site.

Preferred polyalkyl groupε include polyiεobutyl groupε having at least about 30 carbon atoms, more preferably at least about 50 carbon atomε. Especially preferred are polyisobutyl groups having an average molecular weight of about 500 to about 5000, more preferably from about 900 to about 2500.

Preferred lower alkyl groups include methyl and ethyl; eεpecially preferred iε ethyl.

Preferred Am groupε include those having the formula f(ZNH)pZ']- wherein Z and Z' are independently alkylene of 2 to 6 carbon atomε and p iε an integer from 0 to 5. Eεpecially preferred are Am groupε wherein Z and Z' are ethylene and p iε 1, 2 or 3.

Preferred are random polysuccinimides where the average sum of A and B units is from about 2 to about 50. preferred are random polysuccini ideε having molecular weightε of from about 10,000 to about 150,000.

Preferred are compoundε in which the bis-succinimide structure predominates, that is those having more B unitε than A unitε, preferably on the order of about 2 to about 10 timeε as many B units as A units. Such compounds are preferred in part due to their high average molecular weights, on the order of about 10,000 to about 150,000 which may be related to their exhibiting an advantageous V.I. credit as well as disperεantability when uεed in a lubricating oil composition.

It is believed that polysuccinimide compounds in which a significant portion comprises a bis-polyεuccinimide structure (an embodiment which is exemplified in FIG. 1)

3?

comprise network or ladder polymers. Such polymers are cross-linked in an orderly manner. It is believed that this orderly cross-linking allows for the formation of composi- tions having very high molecular weights, on the order of about 10,000 to about 150,000 and also contributes to the advantageous properties of these compositions including improved dispersancy and V.I. credit. In addition, due to the cross-linking of the copolymer molecules by the poly- amine to form the polysuccinimides of the above-noted structure, such products are harder to hydrolyze and are more stable to shear forces than are those polysuccinimides which do not form the ladder structure.

(c) Higher Polysuccinimides

Higher polysuccinimides are prepared by reacting the copoly- mers of the present invention with a polyamine having branching such that it can react with a succinic group from each of greater than two copolymer molecules. Due to this crosslinking, it is believed that these higher polysucci- nimides may have gel-like properties besides the dispersant properties possessed by the other polysuccinimides.

C. POLYAMINO POLYSUCCINIMIDES WHEREIN ONE

OR MORE OF THE NITROGENS IS SUBSTITUTED WITH HYDROCARBYL OXYCARBONYL, HYDROXY HYDROCARBYL OXYCARBONYL, OR HYDROXY POLY(OXYALKYLENE)OXYCARBONYL)

OR THE POLYSUCCINIMIDE IS OTHERWISE POST-TREATED Commonly-assigned U.S. Patent No. 4,612,132 discloseε poly- amino alkenyl or alkyl succinimides wherein one or more of the nitrogens of the polyamino moiety is substituted with a hydrocarbyl oxycarbonyl, or a hydroxy hydrocarbyl oxycar- bonyl wherein said hydrocarbyl containε from 1 to about 20 carbon atomε and said hydroxy hydrocarbyl contains from about 2 to about 20 carbon atoms which may be prepared by

^• f reaction with a cyclic carbonate; by reaction with a linear mono- or polycarbonate; or by reaction with a εuitable chloroformate and hydroxy poly(oxyalkylene)oxycarbonyl which may be formed by reaction with a suitable chloroformate. U.S. Patent No. 4,612,132 also discloεeε processes for the preparation of such modified polyamino alkenyl or alkyl succinimides.

U.S. Patent No. 4,612,132 also discloεeε the poεt-treating of hydroxyhydrocarbyl carbamateε prepared from polyamino alkenyl or alkyl succinimideε with an alkenyl or alkyl succinic anhydride.

in addition, U.S. Patent No. 4,612,132 discloses the reac- tion of the modified succinimides disclosed therein with boric acid or similar boron compound to give borated disperεantε. Accordingly, the disclosure of U.S. Patent No. 4,612,132 is incorporated herein by reference.

Commonly asεigned U.S. Patent No. 4,585,566 diεcloεeε improved dispersantε prepared by reacting other nitrogen-containing diεpersants with cyclic carbonateε, the diεcloεure of which is incorporated herein by reference.

Accordingly, by following the procedures disclosed in U.S. Patents Nos. 4,612,132 and 4,585,566, modified polyεuccini- mideε may be prepared. Thuε, the polyamino polyεuccinimides wherein one or more of the nitrogens of the polyamino moiety is subεtituted with a hydrocarbyl oxycarbonyl, or a hydroxy hydrocarbyl oxycarbonyl wherein εaid hydrocarbyl contains from 1 to about 20 carbon atoms and said hydroxy hydrocarbyl contains from 2 to about 20 carbon atoms may be prepared by reaction with a cyclic carbonate; by reaction with a linear mono- or poly-carbonate; or by reaction with a suitable

n />/

chloroformate. Hydroxy poly(oxyalkylene) oxycarbonyl may be formed by reaction with a suitable chloroformate. Also, hydroxy hydrocarbyl carbamates prepared from the polysucci- nimides of the present invention may be post-treated with an alkenyl or alkyl succinic anhydride [or even the copolymers of the preεent invention (εuch aε polyPIBSA) according to the procedures diεcloεed in U.S. Patentε Nos. 4,612,132 and 4,585,566. The products so produced are effective disper- sant and detergent additives for lubricating oils and for fuel.

The polyεuccinimideε and modified polysuccinimides of this invention can also be reacted with boric acid or a εimilar boron compound to form borated diεperεantε having utility within the εcope of thiε invention. In addition to boric acid (boron acid), examples of suitable boron compounds include boron oxides, boron halides and eεterε of boric acid. Generally from about 0.1 equivalentε to 10 equiva- lentε of boron compound to the polyεuccinimide or modified polyεuccinimide may be employed.

Commonly-aεεigned U.S. Patent No. 4,615,826 diεcloεes the treating of a succinimide having at least one baεic nitrogen with a fluorophoεphoric acid or ammonium εalt thereof to give a hydrocarbon-soluble fluorophosphoric acid adduct.- Accordingly, the disclosure of U.S. Patent No. 4,615,826 is incorporated herein by reference.

By following the disclosure of U.S. Patent No. 4,615,826, hydrocarbon-soluble fluorophosphoric adducts of the poly- succinimideε of the present invention may be prepared. Such adducts comprise the reaction product of a polysuccinimide of the present invention and a fluorophosphoric acid or

ammonium salt thereof wherein the amount of said fluoro- phosphoric acid or salt thereof is from about 0.1 to about 1 equivalent per equivalent of basic nitrogen atom.

The copolymers of the present invention, including preferred copolymerε such as polyPIBSA may be post-treated with a wide variety of other post-treating reagents. U.S. Patent No. 4,234,435, the disclosure of which is incorporated herein by reference, discloses reacting succinic acylating agents with a variety of reagents to give post-treated carboxylic acid derivative compositionε which are useful in lubricating oil compositions.

D. LUBRICATING OIL COMPOSITIONS

The copolymers, polysuccinimides and modified polysuccini- mideε of this invention are useful as detergent and disper- εant additiveε when employed in lubricating oilε. When employed in this manner, the additives of the present invention are usually present in from 0.2 to 10 percent by weight to the total composition and preferably at about 0.5 to 8 percent by weight and more preferably at about 1 to about 6 percent by weight. The lubricating oil used with the additive compoεitionε of thiε invention may be mineral oil or synthetic oils of lubricating viscosity and prefer- ably suitable for uεe in the crankcase of an internal combustion engine. Crankcase lubricating oils ordinarily have a viscosity of about 1300 CSt 0°F to 22.7 CSt at 210°F (99°C). The lubricating oils may be derived from synthetic or natural sourceε. Mineral oil for uεe aε the base oil in thiε invention includeε paraffinic, naphthenic and other oilε that are ordinarily used in lubricating oil composi- tions. Synthetic oils include both hydrocarbon synthetic oils and synthetic esters. Useful synthetic hydrocarbon

If oils include liquid polymers of alpha olefins having the proper viεcosity. Eεpecially useful are the hydrogenated liquid oligomers of C _β to C, ₂ alpha olefins such as 1-decene trimer. Likewise, alkyl benzeneε of proper viεcoεity, εuch as didodecyl benzene, can be used.

Blends of hydrocarbon oils with synthetic oils are also useful. For example, blends of 10 to 25 weight percent hydrogenated 1-decene trimer with 75 to 90 weight percent 150 SUS (100°F) mineral oil gives an excellent lubricating oil base.

Lubricating oil concentrates are alεo included within the εcope of thiε invention. The concentrateε of thiε invention uεually include from about 90 to 10 weight percent, prefer- ably from about 90 to about 50 weight percent, of an oil of lubricating viεcosity and from about 10 to 90 weight per- cent, preferably from about 10 to about 50 weight percent, of an additive of this invention. Typically, the concen- trates contain εufficient diluent to make them easy to handle during shipping and storage. Suitable diluents for the concentrates include any inert diluent, preferably an oil of lubricating viscosity, so that the concentrate may be readily mixed with lubricating oils to prepare lubricating oil compositionε. Suitable lubricating oilε which can be used as diluents typically have viscoεitieε in the range from about 35 to about 500 Saybolt Univerεal Seconds (SUS) at 100°F (38°C), although an oil of lubricating viscosity may be used.

Other additives which may be present in the formulation include rust inhibitors, foam inhibitors, corrosion inhibitors, metal deactivators, pour point depressants, antioxidants, and a variety of other well-known additives.

^

It is also contemplated the additives of this invention may be employed as disperεants and detergents in hydraulic fluids, marine crankcase lubricants and the like. When so employed, the additive is added at from about 0.1 to 10 percent by weight to the oil. Preferably, at from 0.5 to 8 weight percent.

E. FUEL COMPOSITIONS

When used in fuels, the proper concentration of the additive necesεary in order to achieve the desired detergency is dependent upon a variety of factors including the type of fuel used, the presence of other detergents or dispersantε or other additives, etc. Generally, however, and in the preferred embodiment, the range of concentration of the additive in the baεe fuel iε 10 to 10,000 weight partε per million, preferably from 30 to 5000 partε per million of the additive per part of base fuel. If other detergents are present, a lesser amount of the additive may be used. The additives of this invention may be formulated as a fuel concentrate, using an inert stable oleophilic organic solvent boiling in the range of about 150° to 400°F. Preferably, an aliphatic or an aromatic hydrocarbon solvent is uεed, εuch a benzene, toluene, xylene or higher-boiling aromaticε or aromatic thinnerε. Aliphatic alcoholε of about 3 to 8 carbon atoms, such as isopropanol, isobutylcarbinol, n-butanol and the like, in combination with hydrocarbon εolvents are also suitable for use with the fuel additive. In the fuel concentrate, the amount of the additive will be ordinarily at least 5 percent by weight and generally not exceed 70 percent by weight, preferably from 5 to 50 and more preferably from 10 to 25 weight percent.

The following exampleε are offered to εpecifically illuεtrate this invention. These exampleε and illustrations are not to be construed in any way limiting the scope of thiε invention.

EXAMPLES Example 1

Preparation of Polyisobutyl-24 PolyPIBSA

To a 12-liter, 3-neck flask equipped with an overhead stirrer, thermometer, condenser, and heating mantle under nitrogen atmosphere was added 5,000 grams (5.265 mole) of polyisobutene of about 950 molecular weight having the trade- name ULTRAVIS-10 obtained from BP Chemicals wherein the methylvinylidene isomer comprised about 70% of the total composition, 1547.1 grams (15.79 mole) maleic anhydride, and 2,500 ml chloroform. The mixture was heated to reflux, and to this was added 67.21 grams (0.41 mole) 22'-azobis (2-methyl-propionitrite) ( "AIBN" ) . The mixture was refluxed for two hours at which time an additional 67.21 grams of AIBN was added. This waε followed by another two hourε of reflux and a third charge (66.58 gramε) of AIBN. A total of 201 grams (1.2 mole) of AIBN was added. The reaction mixture was refluxed a total of 20 hourε, and then allowed to cool. Two layerε formed. The lower phaεe which contained moεtly chloroform and unreacted maleic anhydride waε diεcarded. The upper layer which contained mainly product and unreacted polyiεobutene was separated. Solvent and maleic anhydride were removed in vacuo. A total of 4,360 grams of product having a saponification number of 40.4 was recovered.

H-4-

Example 2 Preparation of Polyisobutyl-24 PolyPIBSA

To a 1-liter 3-neck flask equipped with a thermometer, overhead stirrer, nitrogen inlet and water condenser, was added 165.02 grams (0.174 mole) polyisobutylene (ULTRAVIS-IO from BP Chemicals) and 105 ml dichloroethane, then 16.4 grams (0.167 mole) maleic anhydride were added. The resulting mixture was heated to about 45°C, and 3.3 grams (0.017 mole) tert-butylperbenzoate was added. The resulting mixture was heated to reflux (83°C). The reaction mixture was heated (with stirring) for a total of 30 hours. The reaction mixture was allowed to cool. The solvent was removed in vacuo. Unreacted maleic anhydride was removed by heating the residue to 150°C at 0.1 mm Hg vacuum. A total of 176.0 grams product waε obtained, which had an average molecular weight of about 5000. The conversion was about 60%. The saponification number waε 73.3.

Exampleε 3 to 15 and Compariεon Examples IC to 5C

Table I tabulates additional preparations following the basic synthetic procedure outlined in Examples 1 and 2. Table I listε the reactantε, reaction temperature, time and εolvent, and free radical initiator uεed.

Example 12 waε prepared uεing polyisobutene of about 1300 molecular weight having the trade name ULTRAVIS-30 obtained from BP chemicals wherein the methylvinylidene isomer comprised about 70% of the total composition.

Comparison Examples IC to 5C were prepared uεing a polyisobutylene of about 950 molecular weight prepared with

< ~

4b

TABLE I (Cont'd)

Product of Maleic Example Polybutene Anhydride Solvent Initiator* Temp

No. (g) (ml) ⁽ 2 ⁾ °C

14 Ultravis-10 515.8 Chloroform TBPB 72 (5000) (3000) (102.8)

15 Chloroform TBPB 72 (6000) (205.6) then 140

IC Toluene AIBN 110 (250) (15.5)

2C Dichloroethane AIBN 83 (50) (2.33) 3C Toluene DTBP 110 (210) (5.8) 4C Xylene DTBP 114 (210) (5.8) 5C Chlorobenzene DTBP 138 (210) (5.8)

* AIBN = 2,2'-azobis (2-methyl-propionitrite) ; DTBP = ditertbu peroxide; TBPB « tertbutyl peroxybenzoate

** Molecular weight 1300

Example 16

A 500-ml, 3-necked flaεk waε charged with lOOg of a polyPIBSA polybutene mixture (prepared according to the method of Example 5) which comprised about 38 weight percent polyPIBSA and about 62 weight percent unreacted polyiso¬ butene (of which about 68 weight percent comprised the methylvinylidene isomer). The mixture was heated to 70°C. Then, 8g maleic anhydride and 1.7g di-tert-butyl peroxide were added to the mixture. The mixture was stirred and

heated to 150°C for 5 hours. After allowing the mixture to cool, 150 ml hexane was added to precipitate unreacted maleic anhydride which was then removed by filtration. The hexane was removed by stripping for 4 hours at 36 mm Hg (abε) at 90°C. The product had a maleic anhydride content of 0.08 weight percent.

Example 17A

A 22-liter, 3-necked flaεk waε charged with 3752g of polyiεobutene (BP Ultraviε 10) and 2800g of a polyPIBSA polyiεobutene mixture (prepared according to Example 13) which compriεed about 57 weight percent polyPIBSA and about 43 weight percent unreacted polyiεobutene). The mixture waε heated to 91°C; then 14g maleic anhydride and 2.7g di-tert-butyl peroxide (DTBP) were added. A εlight exotherm waε noticed where the temperature increaεed to 147°C. The mixture waε εtirred and heated at 140°C for one hour. After εtanding at room temperature overnight, the mixture waε heated to 140°C and 378g maleic anhydride and 56.7g of DTBP were added. The mixture waε εtirred and heated at 140°C for 6-5 hourε. The mixture waε allowed to cool to ambient temperature overnight. The mixture waε heated to 80°C and vacuum waε applied at 28 inches Hg (vac); the temperature was increased to 200°C. The mixture was stripped at 200°C and 28 inches Hg (vac) for 2 hours to remove unreacted maleic anhydride.

Example 17B

A 22-liter, 3-necked flaεk was charged with 8040g polyisobutene (BP Ultravis 10) and 6000g of a polyPIBSA/polybutene mixture prepared according to Example 17A. The mixture was heated to 109°C, then 840g

maleic anhydride and 126g DTBP were added. The reεulting mixture waε ^" εtirred and heated at 140°C for 5.25 hours. The mixture was cooled to ambient temperature. The mixture was then heated to 128°C with stirring and an additional 153g maleic anhydride and 23g DTBP were added. The mixture was stirred and heated at 140°C for 3.5 hours and then an additional 153g maleic anhydride and 11.8g DTBP were added. The mixture was stirred and heated at 140°C for an additional 3.67 hours. The mixture was cooled to ambient temperature. The mixture was then stirred and heated at 186°C for one hour while vacuum was applied to strip the unreacted maleic anhydride from the product. The product had a εaponification number of 85.8 mg KOH/g.

Example 18

Preparation of PolyPIBSA TETA Polyεuccinimide with a High Degree of Polymerization

To a 12-liter flask equipped with a Dean Stark trap, overhead stirrer and heating mantle under nitrogen was added 4340 g polyPIBSA prepared according to Example 1 (εaponification No. 40.4 mg KOH/g, molecular weight about 9000). The reεulting mixture waε heated to 130°C with stirring, then 163.7g (1.12 mole) triethylenetetraamine (TETA) were added. The reaction mixture was εtirred overnight at 160 ^β C to 215 ^β C; 24 ml water were collected (in the Dean Stark trap) The reaction mixture waε allowed to cool.

Obtained waε 4360 g of a polyεuccinimide of about 58,000 molecular weight having the following characteriεtics: 1.45%N, TAN 1.01, TBN 26.9, viscosity at 100 ^B C 2649 cSt. The molecular weight was determined using 1-lOOθA and 1-500A

41 ultrastyrogel columns connected in series using 10% propylamine 90% THF as a solvent and comparing the retention time with known (molecular weight) polystyrene standards.

Example 19

Preparation PolyPIBSA TEPA

Polysuccinimide With a High Degree of Polymerization To a 3-neck one-liter flask equipped with heating mantle, overhead stirrer and Dean Stark trap, waε added 213.4 g polyPIBSA prepared according to the method of Example 5 (molecular weight about 6000). The system was heated to 90°C with stirring; then 18.98 g of tetraethylene pentaamine (TEPA) (0.1003 g). The resulting mixture was heated to 176°C under nitrogen sweep. A small amount of water (about 0.5 ml) was removed. After 3.5 hours, the mixture was placed under vacuum and was heated under vacuum for 0.5 hours; the heating was then stopped. Obtained was 226.9 g of product, a polyPIBSA TEPA polysuccinimide.

Example 20

Preparation of PolyPIBSA TETA

Polysuccinimide With a High Degree of Polymerization To a 12-liter flask equipped with an overhead stirrer, heating mantle and Dean Stark trap, under nitrogen sweep, was added 4539 g polyPIBSA prepared according to Example 5 (saponification number 36.3, molecular weight about 6600). The system was heated to 125°C with εtirring; then 131.6 g triethylene tetraamine (TETA) waε added. The reaction mixture waε heated to 165°C for 5 hours. A total of 21.5 ml water was collected in the Dean Stark trap. The mixture was then heated under vacuum at 180°C for two hourε. The reaction mixture waε allowed to cool. Obtained was 4589 g

sv

01 of product, a polyεuccinimide of about 35,000 molecular

02 weight having the following characteriεticε: %N 1.14, TAN

03 2.33, TBN 20.1, viscosity at 100°C 1817 cSt. 04

05 Example 21

06

07 Preparation of PolyPIBSA TETA nn Polysuccinimide with a Low Degree of Polymerization

09 To a 5-liter flask equipped with a heating mantle, overhead

10 stirrer and Dean Stark trap under nitrogen sweep, was added

11 1000 g polyPIBSA prepared according to Example 17B

12 (εaponification number 85.8, molecular weight about 2500)

13 and 999 g Chevron 100NR diluent oil. The mixture waε heated

14 to 60°C; then 75.78 g TETA waε added. The mixture waε

15 heated to 160 ^β C and kept at temperature for 4 hours. A

16 total of 7.0 ml water was recovered from the Dean Stark

17 trap. The reaction mixture waε then maintained at 160°C

18 under vacuum for 2 hourε. The reaction mixture waε allowed

19 to cool. Obtained waε 2018.2 g of product having %N=1.35. 20

21 Example 22

22

23 Preparation of PolyPIBSA HPA

_ . Polyεuccinimide With a Low Degree of Polymerization

25 To a 5-liter flask equipped with a heating mantle, overhead

26 εtirrer and Dean Stark trap (under nitrogen sweep) was added

27 1000 g polyPIBSA prepared according to Example 17B

28 (saponification number 85.8 molecular weight 2500) and 932

29 Chevron 100NR diluent oil. The mixture was heated to 60°C;

30 to this was added 142.45 g heavy polyamine ("HPA") No. X

31 obtained from Union Carbide Corporation. The mixture became 2 very thick. The reaction mixture was heated to 165°C and 3 maintained at that temperature for 4 hourε; the mixture 4 became leεε viscous. Then the reaction mixture was heated

_T7

at 165°C under vacuum for 2 hours. The mixture was allowed to cool. Obtained was the above-identified product having %N=2.23.

Example A

Determination of Saponification Number

Saponification number was determined by using ASTM procedure D94-80.

Resultε for the products of Examples 2 to 15 and IC to 5C are given in Table II.

Example B

Determination of Percent Unreacted Polyisobutylene and Percent Product

The percent of unreacted polyisobutylene and percent product were determined according to the following procedure.

A 5.0-gram sample of product was dissolved in hexane, placed in a column of 80.0-gram silica gel (Davisil 62,14θA pore εize εilica gel), and eluted with 600 ml hexane. The percent unreacted polybutylene waε determined by removing the hexane εolvent in vacuo (from the eluent) and weighing the reεidue. The εilica gel from the column was removed and εuspended in a 1-liter beaker with 250 ml dioxane. The mixture was heated to boiling, and the filtered. The process was repeated three more times. The dioxane solutionε were combined and then εtripped to dryneεε i_n vacuo and the percent product determined by weighing the reεidue.

Results for the Products of Examples 2 to 15 and IC to 5C are tabulated in Table II.

Example C

Determination of Molecular Weight of The PolyPIBSA Product and Degree of Polymerization

The molecular weight of the product was determined according to the following procedure.

A 0.5% solution of product in tetrahydrofuran was injected onto two 500-A gel permeation columns (ultrastyrogel) connected in εerieε. The εolvent used was 1 to 3 percent methanol in tetrahydrofuran. (The columns were eluted with a 1% or 3 percent solutions methanol in tetrahydrofuran.) Molecular weight was determined by comparison of retention times of the product to the retention times of polystyrene standards.

Degree of polymerization was calculated by dividing the molecular weight by 1,050 (the calculated average molecular weight of a monomer having one succinic group and one polyisobutylene group of average molecular weight of 952).

Results for the products of Examples 2 to 15 and IC to 5C are tabulated in Table II.

Example D Calculation of "PIBSA Number"

The PIBSA number was calculated by dividing the εaponification number by the percent product. Thiε gave the "PIBSA number" which iε a εaponification number for

_T3

polyPIBSA on a 100% actives basiε. Thiε value iε tabulated n Table III.

Calculated PIBSA numbers for the products of Exampleε 2 to 15 and IC and 5C are tabulated in Table III.

It iε believed that polyPIBSA compriseε a copolymer having alternating succinic and polyisobutyl groups.

Example E

Fourier Transform Infrared Spectra of PolyPIBSA

The Fourier Transform Infrared (FTIR) Spectra (having a resolution of 2 cm- ) of some of the polyPIBSA copolymers of the present invention and also some comparison compounds were recorded on a Nicolet MX-1 FTIR. Samples whose spectra was to be run were prepared by dissolving in Chevron 100NR mineral oil at a concentration of 5 percent by weight. The FTIR frequency for the anhydride stretch for each sample was measured and is recorded in Table IV.

As may be seen from Table IV, PIBSA prepared by the thermal proceεs ("thermal PIBSA") prepared from (a) BP ultravis polyisobutene (having about 70% of the total composition in the methylvinylidene configuration) and (b) Exxon Parapol polyisobutene both exhibited the anhydride stretch frequency at 1793 cm- . PIBSA prepared according to the chlorination proceεε ("Chlorination PIBSA") from the Exxon Parapol polyiεobutene had an anhydride εtretch frequency at 1785 cm ^" . In contrast, copolymers of the present invention comprising polyPIBSA (prepared according to Examples 3 to 12) exhibited anhydride stretch frequencies in the range of 1777 to 1783 cm ^" . Comparison Examples IC to 5C which were

_r prepared by reacting the Exxon Parapol polyiεobutene (which did not compriεe at leaεt about 20 percent of the alkyl- vinylidene iεomer) under free radical conditionε exhibited anhydride stretch absorbences in the range of 1785 to 1790 cm the range for the conventional PIBSA materials. It is believed that these differences are due to the 2,3-disubsti- tution that is preεent in the one-to-one alternating copolymers of the present invention.

Example F

Fourier Transform Infrared Spectra of Polyεuccinimideε

The Fourier Transform Infrared (FTIR) spectra of some of the polysuccinimides of the present invention and also of some comparison compounds were recorded. Samples were prepared as described in Example E and the FTIR frequency for the succinimide stretch for each sample is recorded in Table V.

As may be seen from Table V, MS-Th, monosuccinimide prepared from Thermal PIBSA and BS-Th, bis-εuccinimide prepared from Thermal PIBSA exhibit the succinimide stretch at 1705.1 cm ^" and 1707.0 cm- , respectively. MS-C1 monosuccinimide prepared from chlorination PIBSA, PS-Cl, a polysuccinimide prepared from chlorination PIBSA and CS-CL, a commercial succinimide prepared from chlorination PIBSA, exhibit succinimide stretcheε at 1706.2 Cm ^" , 1705.1 cm ^" and 1705.1 cm ^" , reεpectively.

In contrast, the polysuccinimideε of the preεent invention exhibit succinimide stretches between about 1697 cm ^" and about 1703 cm ^" . It iε believed that the characteristic frequency for the succinimide stretch is due to the disubstitution at the 2- and 3-poεitionε in the

■

polyεuccinimide εtructure, εimilar to the characteriεtic anhydride εtretch exhibited by the polyPIBSA copolymerε.

Example G Sequence VE Test - Sludge

Formulated oils containing a polyεuccinimide of the preεent invention prepared according to Example 18 were tested according to the Sequence VE Engine Test Procedure (Sequence VE Test Procedure, Seventh Draft, May 19, 1988) and evalu- ated for εludge. The teεt formulationε were compared with two induεtry reference oils: Reference A, a poor performing oil, and Reference B, a good performing oil. Sludge ratings of 9 or greater are advantageous and generally considered passing. Resultε are tabulated in Table VI.

TABLE II Averag Saponifica- Degree tion of Product Weight Value, % Molecular Poly- of Product, mgKOH/g Unreacted % Wt. meriza Example g Sample Polybutene Product Product tion

2 176 73 . 3 40 60 5 , 000 4 . 8 3 370 N/A 59 39 1,700 1.6 4 355 78.9 36 58 1,350 1.3 5 4,589+ 36.3 64 36 6,600 6.3 6 374+ 45.4. 62 37 9,100 8.7 7 365+ 43.3 57 43 11,000 10.5 8 357 78. ^' 3 36 60 1,400 1.3 9 364 78.4 40 53 1,200 1.1 10 361 79.8 39 58 1,300 1.2 11 341 35.8 65 32 1,900 1.8 12 232 ^' 39.6 35 65 8,000 5.7 13 3,605 80.3 35 57 1,350 1.3

50>

1

/ TABLE V

FTIR Spectra of Polysuccinimides

Sample-Product _ ₁ of Example No. FTIR Frequency (cm

18 1697.5 19 N/A 20 1699.2 21 1700.4 22 1699.4

MS-Th (mono-succinimide-thermal PIBSA) 1705.1 BS-Th (bis-succinimide-chlorination PIBSA) 1707.0 MS-Cl (mono-succinimide-chlorination PIBSA) 1706.2 PS-Cl (polysuccinimide-chlorination PIBSA) 1705.1 CS-Cl (commercial succinimide-chlorination PIBSA) 1705.1

N/A = not available.

ύ-

To a 2 liter 3-necked flask equipped with an overhead stirrer, condensor and nitrogen inlet tube was added 677.0 g polyPIBSA, prepared according to Example 33, with a high degree of polymerization and 950 molecular weight polybutene tail (SAP No. 64.4, 0.389 mol). To this was added 267 g Chevron 100N diluent oil. This was then heated to 120°C under nitrogen with εtirring and 36.7 g TEPA (0.194 mol) was added rapidly. This waε εtirred for 4 hours at 160°C. A total of 5.8 cc. water was produced. This produced a

ϋ l

bisTEPA polyεuccinimide with a high degree of polymeri- zation. Then the temperature waε lowered to 80°C and 102.43 g ethylene carbonate waε added (1.16 mol). This amount was required so that two moles of ethylene carbonate reacted with each basic nitrogen in the bisTEPA poly- succinimide. The temperature waε increaεed to 160°C for 4 hours. A total of 1004.51 g of product was produced. The product had the following propertieε: Acid No. - 0.08 mg KOH/g; %N « 1.23%; Alkalinity Value - 14.18 mg KOH/g; and viεcosity at 100°C ^~ - 901.2 Cst.

EXAMPLE 24

Preparation of Ethylene Carbonate Treated Bis TEPA Polysuccinimide with a Low Degree of Polymerization

To a 2 liter 3-necked flask equipped with an overhead stirrer, condensor and nitrogen inlet tube was added 497.0 g polyPIBSA prepared according to Example 17B with a low degree of polymerization and 950 molecular weight polybutene tail (Saponification No. 85.8, 0.38 mol). To this was added 447 g Chevron 100N diluent oil. This was then heated to 120 ^β C under nitrogen with stirring and 35.9 g TEPA (0.19 mol) was added rapidly. This was stirred for 4 hours at 160°C. A total of 5.9 cc. water was produced. This produced a bisTEPA polysuccinimide with a low degree of polymerization. Then the temperature waε lowered to 80°C and 100.32 g ethylene carbonate waε added (1.14 mol). Thiε amount was required so that two moles of ethylene carbonate reacted with each basic nitrogen in the bisTEPA polysucci¬ nimide. The temperature was increaεed to 160°C for 4 hours. A total of 1030.0 g of product waε produced. The product had the following propertieε: Alkalinity Value 14.0 mg KOH/g.

01 EXAMPLE 25

02

03 Preparation of Borated Biε HPA Polysuccinimide _ with a High Degree of Polymerization

05

To a 2 liter 3-necked flask equipped with an overhead 06 stirrer, condensor and nitrogen inlet tube was added 864.0 g 7 polyPIBSA made in a manner similar to Example 35, with a 8 high degree of polymerization and 950 molecular weight 9 polybutene tail (Saponification No. 49.0, 0.38 mol). To 0 . this was added 121 g Chevron 100N diluent oil. This was then heated to 140°C under nitrogen with stirring and 52.3 g 2 HPA (0.19 mol) was added rapidly. This waε εtirred for 4 3 hourε at 170°C. A total of 7.5 cc. water waε produced. 4 This produced a bisHPA polysuccinimide with a high degree of 5 polymerization. Then the temperature was lowered to 65°C 6 and 50 cc water and 27.09 g boric acid (0.44 mol) was added. 7 Thiε was heated at reflux (102°C) for 2 hourε, then the 8 water was removed by distillation. The temperature was then 9 increaεed to 171 ^β C for 2.5 hours. Then the product waε 0 decanted. The product had the following propertieε: Acid 1 No. = 2.30 mg KOH/g; %N « 1.68%; .Boron = 0.53; and viε- 2 coεity at 100°C ■= 1014 Cεt. It iε anticipated that thiε 3 borated product will have improved wear propertieε. 4 5

EXAMPLE 26 6 7

Preparation of Borated Biε TEPA ⁸ Polyεuccinimide with a Low Degree of Polymerization 9 0 To a 2 liter 3-necked flaεk equipped with an overhead εtirrer, condenεor and nitrogen inlet tube waε added 500 g polysuccinimide from Example 46. This was then heated to ³ 50°C under nitrogen with stirring and 50 ml water and 28.2 g ⁴ boric acid (0.45 mol) was added. This was then heated at

reflux (102°C) for 2 hours. Then the water was distilled off, and the temperature was increased to 165°C for 1.5 hours. A total of 517.0 g of product was produced. The product had the following properties: %N - 1.24; viscosity at 100°C - 312.5 Cst; Acid No. ■ 24.3 and %B « 1.01%. It iε anticipated that thiε borated product will have improved wear propertieε.

EXAMPLES 27 to 36

Table VII includes the results from additional preparations of polyPIBSA that were carried out using the basic synthetic procedure outlined in Examples 1 and 2. Table VII lists the reactants, reaction temperature, time and solvent and free radical initiator used as well as the weight of product and the saponification value.

Weight Saponification Time Product . value

°c hrs (g) mg KOH/g Sample

138 30 345 51

138 38

83 55

142 67

83 47

90 46

91 64.4

Saponification valve mg KOH/g Sample

34

51

50

[p k

EXAMPLES 37 to 48

Table VIII includes the resultε from additional preparationε of polyεuccinimides that were carried out using the basic εynthetic procedure outlined in Exampleε 18-22. Table VIII lists the polyPIBSA used, the amount of diluent oil added, the polyamine used, the calculated charge mol ratio (CMR), the weight of final product, the water produced, and the %N.

%N

2.94 6.2

0.99 9.1

1.79 15.0

0.98 12

0.92 13

1.8 16.5

1.13 14

2.14 13

1.50 3.6

**In this example, extra i uent o (18.4 ) was a ded to the polyPIBSA to make it easier to filter.

EXAMPLE 49

Viton Seal Swell Teεt

Some lubricating oil additives have been identified as being deleterious to fluoroelastomers such as Viton that are currently used as gasket materials in automobile engines. European engine builderε have now placed fluoroelaεtomer seal testε into their engine oil specifications. One such test is the Volkswagen V 3334 (September 1987) Seal Swell Test. This procedure is deεcribed in the Third Sympoεium of the European Coordination Council (CEC) 1989 in an article entitled "Engine and Bench Aging Effects on the Compatibility of Fluoroelaεtomerε with Engine Oilε" by Dr. S. W. Harriε and J. C. Downey of Amoco Petroleum Additiveε Company.

The VW3334 (September 1987) Seal Swell Teεt waε carried out on εampleε of Viton from the Parker Prudifa Company which were cut into dumbbell shapes, using a formulated lubricating test oil that contained succinimide disperεant, overbaεed detergent, antioxidant and viεcosity index improver materials at a bath temperature of 150°C for a 96 hour immersion time. The immersion procedure was similar to ASTM D471-79 Standard Teεt Method for Rubber Property-Effect of Liquids. Commercial succinimide dispersants were compared to the polysuccinimideε of preεent Exampleε 47 and 48. The Viton samples were then subjected to analysis of their tensile properties using procedures εimilar to ASTM D412-87 Standard Test Method for Rubber Properties in Tension. The properties that were measured were cracking at 120 percent elongation, percent change in tensile strength and percent change in elongation at break, in accordance

7-

with the VW3334 Seal Swell Test requirementε. The reεultε are εhown in Table IX.

The data in Table IX demonεtrateε that the polysuccinimide of Example 47 paεsed the Viton Seal Swell Teεt at the 0.07% nitrogen level, whereas the commercial bis-succinimide failed. Although the polysuccinimide of Example 48 did not pass the Viton test at the 0.13% nitrogen level, it performed better in this test than the commercial mono- εuccinimide at the 0.12% nitrogen level.

TABLE IX

VITON SEAL SWELL TEST

Sample

Commercial monosuccinimide Polysuccinimide, Example 48 Commercial bis-succinimide Polysuccinimide, Example 47

passing limit +20 +25 No

Tensile strength % change 2 Elongation to break % change Cracks, yeε or no at 120% elongation

l

EXAMPLE 50

This example showε that after the copolymer of the preεent invention is formed, unreacted polybutene can be reacted with maleic anhydride to form thermal process PIBSA.

PolyPIBSA prepared in a manner similar to Example 17B having a Saponification No. of 86 was charged to a reactor and heated to 204°C. A molar equivalent of maleic anhydride (43.3 g), relative to unreacted non-vinylidene polybutene, waε added and the mixture heated to 232°C and held at this temperature for 4 hours. The temperature was reduced to 210°C and the presεure was reduced to 28 inches of mercury. The reduced preεεure and temperature waε maintained for one hour. Then the mixture waε filtered. The product had a Saponification No. of 88.