CA1241491A - Sulfomaleation of polyolefins - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

The present invention relates to novel polymers which are sulfomaleic anhydride adducts of an unsaturated hydrocarbon, wherein the novel polymers are produced by contacting sulfomaleic anhydride or deri-vatives with an unsaturated hyrdocarbon to form the novel polymer, which has a ?n of about 900 to about 107.

A method for controlling the viscosity of organic liquids, said organic liquid having a solubi-lity parameter of from about 6 to about 10.5, which comprises incorporating into said organic liquid a minor amount of a polymer which is a sulfomaleic anhydride adduct or sulfoester maleic anhydride adduct with an unsaturated hydrocarbon polymer, said adduct being hydrolyzed and neutralized.

Description

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FIELD OF THE INVENTION
.

The present invention relates to novel poly-~ers which are adducts of sulfomaleic anhydride its isomers or derivatives, with unsaturated organic mole-cules, wherein the novel products are produced by con-tacting sulfomaleic anhydride with an unsaturated poly-mer to form the novel product. In particular the unsaturated polymer carl be a polyolefin polymer ranging in molec~lar weight from about 500 to about 10,000,000.

The resultant adduct of sulfomaleic anhydride and the unsaturated hydrocarbon polymer can be f~ther reacted with: a polyamine, ammonia, amines or metallic bases which will neutralize the sulfonic acid group and react with the anhydride group as well.
The products a~e ionomeric polymers which are useful as tnermoplastic elastomers.

The instant invention further relates to a process for controlling the viscosity of organic liquids by incorporating in said liquid a minor amount of a poly-mer which is a hydrolyzed and neutralized sulfomaleic anhydride adduct with an unsaturated hydrocarbon and, optionally, a cosolvent for the ionic groups of said polymer. A cosolvent is optionally added which will optionally solubilize tne polymer groups and prov;de a reasonable homogeneous mixture of solvent, cosolvent and polymer. The preferred compositions prepared by the method of the instant invention comprise an organic liquid having a solubility parameter of from 6 to 10.5 in combination ~ith the polymer and a non-volatile alcohol or amine as the cosolvent. Solutions of said polymerc are unusually resistant to viscosity loss due to polar additives (such as alcohols) or polar impurities.

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~ACKGROUND OF THE INVENTION

Various unsaturated hydrocarbon poly~ers have been reacted with maleic anhydrides to for~ a variety of ~aleic anhydride adducts of unsaturated hydrocarbon polymers. The reactivity of maleic anhy-dride with many unsaturated hydrocarbon polymers is poor and in some instances, as for example with EPDM
rubber, even employment o extensive heating i9 in-effective. ~ree radical reactions which graft maleic anhydride onto the unsaturated hydrocarbon polymer have been utilized as alternative routes. ~ree radical grafting leads to chain scission, crosslinking and solvent grating if the solvent is sufficiently reac-ti~e. The reaction of sulfomaleic anhydride with theunsaturated hydrocarbon polymer overcomes these afore-mentioned deficiencies in that the sulfomaleic anhydride can be reacted with the unsaturated hydrocar-bon polymer at moderate temperatures in either the bulk or solution state without the employment of free radi-cal initiators. Sub~equent neutralization and reac-tion of the anhydride groups of resultant adduct of sulfomaleic anhydride with unsaturated hydrocarbons ~roduces valuable ionomers which are userul as thermo-pla tic sla3tomer~ and solution viscosifiers~

The rapid decrease in viscosity of liquids with increasing ~emperature on polymer concentration is well-known. Ideally, for many applications (automobile lubricants, etc.) it would be desirable to solve this problem so that viscosity would be insensitive to tem-perature or polymer level. Alternatively, it might be desirable to provide liquid systems whose viscosities actually increase with temperature or increase as poly-mer level is decreased. It is true that with selected 31 2~

polymeric additives it has been possible to reduce substan-tially the viscosity change with temperature which does occur with most oils and similar systems.
These polymer additives, known as viscosity index improvers (or V.I. improvers) are generally high mole-cular weight polymers.

The way in which these additives function can be summarized very briefly. In effect, they perform two functions, i.e., thickening, which merely increases fluid viscosity; and Viscosity Index (V.I.) improve-ment, which corresponds to limited thickening at ambient temperatures and a corre~pondingly greater thickening at elevated temperatures. This can be accomplished by utilizing a polymeric additive which is poorly solvated by the liquid at ambient temperatures;
~owever, at elevated temperatures the polymer is more highly solvated, such that the polymer expands and is a relatively more effective thickener.

While these V.I. Improvers have proven suc-cessful commercially, it is important to note that their effect at reducing viscosity changes with tem-peratures is rather mild. For a typical base oil con-taining a suitable V.I. Improver the kinematic visco-sity will still decrease by a factor of from S to 10 as the temperature increases from 30C to 100C.
Obviously, if it is desired to hold the viscosity roughly constant with such temperature changes current technology has not of~ered an appropriate additive system. Alternatively, it if is desired to hold vis-cosity reasonably constant as the polymer concentration is decreased conventional wisdom has not previously offered that option.

U. S. Patent NoO 3,396,136 dascribes how copolymers of alkenyl aromatic sulfonic acids, when properly neutralized, can be employed as thickeners for nonpolar solvents. Those metal sulfonate systems have been shown to be very effective; however, when employed as to component systems (i.e., ionic polymer plus non-polar solvent) the variation of viscosity with increased temperature is very conventional and predict-able. That is, the solution viscosity decreases mar-kedly as temperature is increased.

U. S. Patent No. 3,396,136 further teaches "in situ" neutralization of the sulfonic acid polymer which, under some conditions, can result in the avail-ability of a small amount of polar cosolvent, i.e., a solvent for the sulfona'ce groups, about equal in amount to the amount of sulfonate groups which are present.
This amount of polar cosolvent is not within the limits of the instant invention, which only optionally requires amounts of the third component (which inter-acts with the ionomeric groups of the ionomer copoly-mer) at levels which range from lO to 600 times the molar equivalence of ionic groups. This level of co-solvent is about one to two orders of magnitude or more higher than employed in the cited art. In addition, the cited patent is restricted to aromatic sulfonate p~lymers. The instant invention describes other poly-mers, such as sulonated ethylene propylene terpoly-mers, sulfonated autyl~ etc., which are a portion of the polymer complex.

U. S. Patent No. 3,366,430 teaches the gelling o organic liquids by the interaction o polar "associative bonds" which includes hydrogen bonding and "ionic cross-linking". Again, this patent specifies that two components are necessary -- the associating polymer (or polymers in some cases) and the non-polar organic liquid. There is no men~ion of a third polar cosolvent except to point out that such polar liquids ~...

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should not be present. Specifically, this patent states (at column 2, line 7) that the hy~rocarbon liquids to which this invention is to be applied should not contain a substantial portion of a miscible proto-lytic liquid, such as methanol. It is clear that the language of this patent limits this invention to gels and further that any amount of polar liquids which are present to an extent where they disrupt those gels are undesirable. The instant invention is distinct from that cited in that amounts of such polar compounds as will break up gel at ambient conditions are often desirable and, in fact, the preferred state is free of any said gel at ambient temperatures.

U. S. Patent No. 3,679,382 teaches the thickening of aliphatic hydrocarbons with synthetic organic polymers which contain olefinically unsaturated copolymerizable acids, amides, hydroxyacrylic esters, sulfonic acids, etc. It is emphasized in this patent (at column 3, line 72) that it is criticaI that in the preparation of such polymers no surface active agent, catalyst or other additive be employed which introduces a metallic ion into the system. Therefore, it is preferred to employ ammonium or amine salts. It is clear that this invention (U. S. Patent No. 3,679,382) specifically precludes the use of metallic counterions and is directed towards amine or ammonium derivatives.
Metallic counterions are very e~fective in the instant invention. Finally, this cited patent does describe (at column 7, lines 13-19) that the addition of alco-hols will reduce the viscosity of the thickened hydro-carbon and alter flow characteristics thereof.

SUMMARY OF THE INVENTION

One embodiment of this invention is the production of ion containing polymers (ionomers) espe-cially sulfonate ionomers, by a non-sulfonation route.
Another embodiment of this invention is the activation of maleic anhydride or its derivatives towards Alder "Ene" reactions or Diels-Alder reactions, such that polymers which have unsaturated sites will readily form adducts. In particular polymers such as EPDM rubbers which do not undergo thermal reaction readily with maleic anhydride will now react facily.

It has been further discovered that the viscosity of organic liquids may be conveniently controlled by incorporating in said organic liquid a minor amount of a polymer which is a sulfomaleic anhydride adduct with an unsaturated hydrocarbon which has been hydrolyzed and neutralized.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 illustrates a graph of viscosity versus concentration for various polymer solutions. The differences between salts of sulfonated EPDM and salts of sulfomaleated EPDM are demonstrated. The latter viscosity much more efficiently in the pressure of polar compounds, such as methanol.

GENERAL DESCRIPTION

The present invention relates to polymers which are sulfomaleic anhydride adducts with unsaturated hydrocarbons which are formed by reacting sulfomaleic anhydride with an unsaturated hydrocarbon in either the solution or the bulk state.

Sulfomaleic anhydride which is represented by the formula: -H ~ ~ SO3H
C--C

is formed by reacting maleic anhydride with sulfur trioxide. Besides sulfomaleic anhydride, one can also employ sulfomaleic acid, sulfofumaric acid, sulfoacrylic anhydride and their various esters, derivatives of either or both of the carboxyl groups.
Examples of sulfomaleic anhydride, its isomers and derivatives which are suitable for this reaction include, but are not limited to, the following:

~O~H COOH SO,C:J GOS:t F=l' 1~ F=l' I~' 3;02 o~O~3 O~o~

SO~Ct ~O~R SO~R
F r ~ ~
~ ~ g~ 0~ ~ O ~ Q ~ 0~

where R - H, alkyl, alkylsilyl, aryl, etc.

The sulfomaleic anhydride is ~eacted wi~h an unsaturated hydrocarbon polymer which is selected from the group consisting of EPDM terpolymers, EPR, poly-isoprene, polybutadienes, Butyl rubber, styrene-buta-diene and styrene-isoprene "random" and block copoly-mers, Butyl rubbers, polybutenes, hydrocarbon resins such as a Escorez resins, etc. Oligomers or polymers which have olefin functionality near the end of the chain are of interest. Such molecules include, but are not limited to, polyisobutene and polybutenes of various molecular weights. Vistanex, Vistanex-J are examples of such polymers. Plastics such as polyethy-lene and polypropylene containing low levels of unsatu-ration are also suitable polyolefins.

The expression "Butyl rubber", as employed in the specification and claims, is intended to include copolymers made from a polymerization reaction mixture having therein from 70 to 99.5~ by weigh~ of an iso-butylene and about 0.5 to 30~ by weight of a conjugated multiolefin having from about 4 to 14 carbon atoms, e.g. isoprene. The resulting copolymer contains 85 to 99.8% by weight of combined isoolefin and 0.2 to 15% of combined multiolefin.

Butyl rubber generally has a Staudinger molecular weight as measured by GPC of about 2`0,000 to about 500,000, preferably about 25,000 to about 400,000 especially about 100,000 to about 400,000 and a Wijs rodine No. of about 0.5 to 50, preferably 1 to 15. The preparation of Butyl rubber is de~cribed in U.S Patent

2,356,128. ~ ~ -,~ ,. ' .

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~ o~ the purposes of this invention, the Butyl rubber may have incorporated therein from about 0.2 to 10% of combined multiolefin; preferably about O.S to about 6~; more preferably, about 1 to about 4~, e.g., 2~.

Illustrative of such a Butyi rubber is Exxon Butyl 365 (Exxon Chemical Co.), having a mole percent unsaturation of about 2.0% and a Mooney visc~sity (ML, 1 + 3. 212~) of about 40 to S0.

Low molecular weight ~utyl rubbers, i.e.
Butyl rubbers having a viscosity average molecular weight o about 5,000 to 85,000, and a mole percent unsaturation of about 1 to about S~, may be sulfonated ~o produce the polymers useful in this invention. Pre-ferably, these polymers have a viscosity average mole-cular weight of about 25,000 to about 60,000.

The EPDM terpolymers are low unsaturated polymers having about 0.5 to about 10.0 wt.% olefinic unsaturation, more preferably about 2 to abou`t 8, most preferably about 3 to 7 defined accordingly to the definition as found in ASTM-1418-64 and is intended to mean terpolymers containing ethylene and propylene in the backbone and an olefin residue in the ~ide chain as result of multi-olefin incorporation in the backbone.
Illustrative methods for producing these terpolymers are found in U.S. Patent 3,280,082, British Patent 1,030,289 and French Patent 1,386,600. The preferred polymers contain about 40 to about 75 wt. ~ ethylene and about 1 ~`~7`' - 10 - ~L2~ 9~

to about 10 wt.~ of a diene monomer, the balance of the polymer being propylene. Preferably, the polymer contains about 45 to about 70 wt.% ethylene, e.g. 50 wt.% and about 2.6 to about 8.0 wt.~ diene monomer, e.g. 5.0 wt.~. The diene monomer is preferably a non-conjugated diene.

Illustrative of these nonconjugated diene monomers which may be used in the terpolymer (EPDM1 are 1,4-hexadiene, dicyclopentadiene, 5-ethylidene 2-norbor-nene, 5-methylene-2-norbornene, 5-propenyl-norbornene, methyl tetrahydroindene and 4-methyl-5-methylene-2-nor-bornene.

A typical EPDM is Vistalon 2504 (Exxon Chemical Co.), a terpolymer having a Mooney viscosity (ML, 1 + 8, 212F) of about 40 and having an e~thylene content of about 50 wt.9~ and a S-ethylidene-2-norbor-nene content of about 5.0 wt.%. The Mn as measured by GPC of Vistalon 250~ is about 47,000, the- Mv as measured by GPC is about 145,000 and the Mw as measured by GPC is about 174,000.

Another EPOM terpolymer Vistalon 2504-20 is derived from Vistalon 2504 (Exxon Chemical Co.) by a controlled extrusion process, wherein the resultant Mooney viscosity at 212F is about 20. The Mn as measured by GPC of Vistalon 2504-20 is about 26,000, the Mv as measured by GPC is about 90,000 and the Mw as measured by GPC is about 125,000.
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Nordel 1320 (Dupont) is another terpolymer having a Mooney viscosity at 212F of about 25 and having about 53 wt.% of ethylene, about 3J5 wt.96 of 1,4-hexadiene, and about 43.5 wt.% of propylene.

The ~PDM terpolymers of this invention have a number average molecular weight (Mn) as measured by GPC of about 10,000 to about 200,000, more preferably of about 15,000 to about 100,000, most preferably of about 20,000 to about 60,000. The Mooney viscosity (ML, 1 + 8, 212~) of the EPDM terpolymer is about 5 to about 60, more preferably about 10 to about 50, most preferably about 15 to about 40. The Mv as measured by GPC of the EPDM terpolymer is preferably below about 350,000 and more preferably below about 300,000. The hw as measured by GPC of the EPDM terpolymer is prefer-ably below about 500,000 and more preferably below about 350,000.

Other suitable olefin polymers include poly-mers comprising a major molar amount of ~2 to Cs mono-olefins, e.g., ethylene, propylene, butylene, isobuty-lene and pentene. The polymers may be homopolymers such as polyisobutylene, as well as copolymers of two or more such olefins such as copolymers of ethylene and propylene, butylene and isobutylene, propylene and isobutylene and the like.

The reaction of the sulfomaleic anhydride or its ester derivatives with the unsaturated hydrocarbon polyme~ can occur in solution, in a melt and in poly-mer processing equipment such as a rubber mill, a Brabender, an extruder or a Banbury mixer.

The polymer of the sulfomaleic adduct with the unsaturated hydrocarbon can be covalently bonded through its anhydride group with molecules containing polar groups. Such polar functionality molecules can be low molecular weight compounds, oliyomers or poly-mers. Of particular interest are molecules containing amine functionality~ Polyamines provide polarity to form molecules with a polar head and a hydrocarbon tail in addition to the ionic sulfon~te site.

The sulfonic acid group of the sulfomaleic anhydride can be neutralized with ammonia, primary secondary or tertiary amines including the aforemen~
tioned amino compounds ~ or metal counterion selected from the group consisting of iron, leadr aluminum and groups IA, I IA, IB and I IB of the Periodic Table of Elements. The neutralization of the sulfonic acid groups of the sulfomaleic anhydride adduct of the un-saturated hydrocarbon polym~r can be accomplishe~
either ' n solution, in a melt or in polymeric process-ing equipment, as previously defined.
The polymer is preferably the sulfomaleic anhydride adduct in which the unsaturated hydrocarbo~ is incorporated into the organic liquid at a concentration level of about 0.1 to about 20 grams pex 100 ml of organic liquid, more preferably about .5 to about 5.
The organic liquid is a hydrocarbon which has a solubility parameter of about 6 to about 10.5, wherein the organic liquid is selected from the group consisting of lubricating oils, synthetic oils, aliphatic oils, naphthenic oils, aromatic oils, aliphatic hydrocarbons, aromatic hydrocarbons and naphthenic hydrocarbons. The organic liquid has a viscosity at 100F of less than about 35 centipoises.

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The method of the instant invention includes incorporating a cosolvent, for example a polar cosol-vent, into the mixture of organic liquid and the poly-mer to solubilize the pendant ionomeric groups. The polar cosolvent will have a solubility parameter of at least 10.0, more preferably at least 11.0, and may comprise from 0.1 to 40 weight percent, preferably .5 to 20 weight of the total mixture of organic liquid, ionomeric polymer and polar cosolvent.

While this definition of polar cosolvent is adequate, we also observe that cosolvents with espe-cially long alkyl groups with hydroxyl groups on one or both ends are especially preferred. These cosolvents are based on Clo-C30 alkyl chains.

In addition to the requirements for ionic polymer, organic liquid and polar solvent there is the additional and more important constraint that the polar cosolvent be more polar than the organic liquid. This is required in order that the proper interaction between polar cosolvent and ionic groups be obtained.
If we designate the solubility parameter of the organic liquid as SL and the solubility parameter of the polar cosolvent as Sp then we require that:
Sp > ~ 1Ø

In other words, the polar cosolvent will be substantially more polar than the organic liquid to be thickened.

., - 14 ~-Normally the polar cosolvent will be a liquid at room temperature, however, this is not a requirement. It is required that the polar cosolvent be soluble or miscible with the organic liquid at the levels employed in this invention. Under normal circumstances this miscibility requirments precludes the use of water as a polar cosolvent. The polar cosolvent must be present in amounts of from 20 to 500 moles per mole of ionic group in order to give the desirable results of the instant invention and preferably from 30 to 400 moles per mole of ionic group. This level of cosolvent is desirable in creating solutions which can be isoviscous with temperature on concentration.

DESCRIPTION OF THE_PREFERRED EMBODIMENTS

The following examples illustrate the pre-sent invention without, however, limiting the same hereto.

Example 1 - EPDM Rubber with Sulfomaleic Anhydride A solution of 50g of dry EPDM Rubber (Vistalon 2504) in 1000 ml of dry xylene was heated at 130C and stirred under nitrogen and 2.679 (15 mmole) of sulfomaleic anhydride was added and heating continu-ed for four Hrs.

After cooling the sulfonic acid was neutra-lized and the anhydride reacted with excess methyl amine (21.2g). The polymer solution became extremely viscous and began to climb the stirrer indicating that a polymeric methylammonium sulfonate ionomer had been - 15 _ ~2~9~

formed. Methanol (50ml) was added to attenuate the strong intermolecular associations and the viscosity decreased.

After standing overnight the polymer was precipitated in a high speed mixer with 4000 ml of isopropyl alcohol-water (70:30), collected on a filter and washed again in the mixer with another portion of IPA-water. A small quantity of Irganox 1010 antioxi-dant was added and the polymer filtered and vacuum dried at 50C.

Microanalysis indicated that the resulting product contained 0.46% S (14.2 mmole/lOOg) and 0.265%
N (18.9 mmole/lOOg).

Treatment of a solution of the modified polymer in 95:5 toluene methanol with excess sodium methoxide in methanol to free ionically bound methyl-amine and isolation as ~he sodium salt gave a product whose analysis showed 0.40% S (12.5 mmole/lOOg) and 0.115~N (8.2 mmole/lOOg).

Example 2 - EPDM Rubber with chlorosulfonyl maleic anhydride According to the method of example 1, 2.95g of chlorosulfonylmaleic anhydride was reacted with 50g of Vistalon 2504 EPDM rub~er, followed by reaction of the sulfonyl chloride and carboxylic anhydride groups with excess methylamine. The polymer was isolated and cleaned as in example one.

Microanalysis indicated the presence of 0.46% S (14.2 mmole/lOOg) and 0.359~ N (25.6 meq/lOOg).
Some gelation of the polymer product was observed.
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Treatment of this polymer with sodium meth-oxide solution and isolation as in example one gave a product whose microanalysis showed 0.39% S (12.2 mmole/
lOOg) and 0.194~ N (13.8 mmole/lOOg).

Example 3 Butyl Rubber with chlorosulfonyl maleic anhyd-ride ~ ccording to the method of example 1, 2.95g of chlorosulfonyl maleic anhydride was reacted with 50g of Butyl Rubber (Exxon 365 ~utyl Rubber). After treat-ment with methylamine, the isolated polymer contained 0.47% S (14.7 mmole/lOOg) and 0.468% N (33.4 mmole/-lOOg). Further reaction with sodium methoxide gave a polymer whose elemental analysis showed 0.45% S (14.4 mmole/lOOg) and 0.215~ N (15.3 mmole/lOOg).

Example 4 EPDM Rubber with 2-chloroformyl-3-sulfoacry-lic anhydride According to the method of example 1, 50g of EPDM (V-25041 and 2.95g of 2-chloroformyl-3-sulfoacry-lic anhydride were reacted. After treatment with methylamine the isolated polymer contained 0.40~ S
(12.5 mmole/lOOg) and 0.445% N (32.1 mmole/lOOg). After treatment with sodium methoxide the isolated polymer gave the following microanalysis: 0.52~ S (16.3 mmole/
lOOg) and 0.205% N (14.6 mmole/lOOg).

ExamE~e S EPDM Rub~er with the methyl ester of chloro-sulfonyl maleic anhydride.

Chlorosulfonyl maleic anhydride was reacted with one molar equivalent of methanol in chloroform solution. The chloroform was removed under vacuum and - 17 _ ~4~9~

3.43g of the resulting product was reacted with 50g of V-2504 EPDM according to the method of Example 1. After treatment with methylamine, the isolated polymer, according to microanalysis contained 0.38 ~ S (11.9 mmole/lOOg) and 0.179% N (12.8 mmole/lOOg). After treatment with sodium methoxide the analysis showed 0.36~ S (11.2 mmole/lOOg) and 0.0~9% N (6.4 mmole/, 10 Og ) .

Example 6 Conjugated Diene ~utyl with sulfomaleic anhydride According to the method of example 1, 2.67g of sulfomaleic anhydride was reacted with SOg of CD
autyl 7614. After treatment with methylamine and iso-lation the product contained 0.38~ S (11.9 mmole/lOOg) and 0.248~ N (17.7 mmole/lOOg).

Example 7 Bulk Reaction of EPDM with sulfomaleic anhydride Vistalon 2504 EPDM (50g) was fluxed on a 3"
electric mill at 120C. Sulfomaleic anhydride (l.OSg) was added slowly. Ater the addition was complete the sample was mixed for a few minutes and zinc stearate (2~35g! was added and mixing continued for a few minutes longer.

The resulting product was a tough elastic material that resembled a crosslinked rubber. However, the ptoduct was soluble in 9S:S toluene:methanol indi-cating that the product was a thermoplastic elastic "ionomer".

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I " _ Example 8 Polyisobutylene with sulfomaleic anhydride About 250g of polyisobutylene (Mn = 900) was dissolved in 200 ml of xylene at room temperature under a nitrogen blanket. To the stirred xylene solu-tion was gradually added 60 g of sulfomaleic anhydride at about 35C. The reaction mixture was refluxed for about eight hours, and then concentrated by roto-evapo-ration. The residue was taken up in 2.5 L of ether and washed twice with 500 ml portions of water. The ether solution was dried over MgS04, filtered, and concen-trated by roto evaporation to give a sulfomaleated product which analyzed for 0.33~ sulfur.

Example 9 Sulfonated EPDM Thermoplastic Elastic Ionomers from EPDM and Sulfomaleic Anhydride Royalene 521 EPDM rubber, 50g ~mill dried) dissolved in 1,000 ml dry xylene was treated with 2.67 g of sulfomaleic anhydride for 4 hours at 130C. After cooling, the resulting product was neutralized with either zinc methoxide, sodium methoxide or zinc acetate in methanol. ~ substantial viscosity increase was noted upon addition of the base. Additional methanol was added when necessary to reduce the viscosity.
Stirring was continued to 0.5 hour and the polymer was isolated from isopropanol in a high speed mixer. The resulting crumb was dried in a vacuum oven at 50C.

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Example 10 Sulfonated EPDM Thermoplastic Elastic Ionomers from EPDM and Sulfomaleic Anhydride Ester (Methoxysulfonyl Maleic Anhydride) According to the method of the previous Example Royalene 521 EPDM rubber in xylene was reacted with sulfomaleic anhydride methyl ester at the rate of 15 or 10 mmole per 100 g of polymeric and the product neutralized and isolated as before.

Example 11 Tensile Properties The products of Examples 9 and 10 were com-pounded with 10 parts zinc stearate and 0.5 parts Irgan x 1010 on a hot mill (140-170C) for 20 minutes. The compounds we~re pressed at 192C into pads which were cut into dumbbells for testing on an Instron (Model 1122).

Tensile results in the Table below show that the products are strong ionomers when compared with the modified EPDM (Royalene 521). The products also compare favorably with sulfonated EPDM, suggesting even stronger associations at a given sulfur level.

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v o ~ U~ ~ o U~ Ln E~
~ V _ u~ ~ _I o ~o _I _I ~ Ul ,~ r IQ O ~ ~. O ~ ) CO
~ aJ g O O X ~P X 1`
E~ u~

_ o ~ o\
~ _l æ
~ o SV 0 a~ s O ~ ~ ~
~ N ~ 8 ~ a~ 3 3 ~ ~ ~ ~ u ~ r ~
~ z u~
o u~
53 ~ ~ .~ r~
~ C
E~ ~ ~ c ~:
u~ o ~ ~ _l ~
,~ ~ ~ cn o o o u~ In O
s ~
E~
' 'Ll '~
v ~
~ ~ U ~ U t~ UV~ Vn ~: 0~ o ~ ~ ~ 0~ 0 3 3 ~ :~ g ,~

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Example 12- Sulfonated EPDM Thermoplastic Elastic IonomerS from EPDM and Sulfomaleic Anhydride Ester (Methoxy5ulfonyl Maleic Anhydride) According to the method of Example 9 Royalene 521 EPDM rubber in xylene was reacted with sulfomaleic anhydride methyl ester or sulfomaleic anhydride trimethyl silylester at the rate of 10 or 30 mole per 100 g of polymeric and the product neutralized and isolated as before.

Example- 13 Sulfomaleic anhydride or maleic anhydride sulfoester-adduct~ with EPDM were hydrolyzed and neutralized during isolation. Solu~ion~ were prepared in xylene-methanol at several concentration9 of polymer and varying methanol content~ A comparison of a zinc ~alt of said polymer with zinc ~alt~ of sulfo-EPDM's ~hows that the material of the instant invention i5 much more efficient at vi3cosification than ordinary sulfonated EPDM zin~ polymers. Even at higher ulfona-tion levels ordinary sulonated EPDM's were inefficient in the pre~en~e of methanol.

Since many modifications and variations of thi~ inv~ntion may be made without departing from the spirit or scope of the invention, it is not intended to limit the spirit or scope hereof to the ~pecific Examples hereof.

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Claims (17)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A polymer which is a sulfomaleic anhydride adduct or sulfoester maleic anhydride adduct with an unsaturated hydrocarbon polymer.

2. A polymer according to claim 1 wherein said unsaturated hydrocarbon polymer is selected from the group consisting of ethylene propylene terpolymers, ethylene propylene copolymers, polyisoprene, Butyl rubber, polybutadiene, and styrene-butadiene, and styrene-isoprene random and block copolymers, poly-propylenes and polyisobutylenes, as well as plastic polypropylene copolymers or polyethylene copolymers.

3. A polymer according to claim 2 wherein the sulfonic acid groups of the sulfomaleic anhydride adduct with the unsaturated hydrocarbon polymer are neutralized with a metal counterion selected from the group consisting of iron, aluminum, lead and Groups IA, IIA, IB and IIB of the Periodic Table of Elements.

4. A polymer according to claim 1 wherein the sulfonic acid groups of the sulfomaleic anhydride adduct with the unsaturated hydrocarbon polymer is neutralized with ammonia or an organic amine.

5. An ionomer according to claim 3 which is useful as a thermoplastic elastic.

6. An ionomer composition wherein the products of claim 5 are compounded with an ionic plas-ticizer.

7. A polymer which is an adduct of a sulfo-maleic anhydride derivative or isomer.

8. Polymer adduct of claim 7 wherein the sulfomaleic derivative or isomer is selected from the group including halosulfonyl maleic anhydride, alkoxy sulfonylmaleic anhydrides, .beta.-sulfoacrylic anhydrides.

9. A method for controlling the viscosity of organic liquids, said organic liquid having a solubi-lity parameter of from about 6 to about 10.5, which comprises incorporating in said organic liquid a minor amount of a polymer which is a hydrolyzed and neutralized sulfomaleic anhydride adduct or sulfoester maleic anhydride adduct with an unsaturated hydrocarbon polymer.

10. The method of claim 9, further including a polar cosolvent wherein said polar cosolvent com-prises from about .1 to about 40 weight percent of the total mixture of said organic liquid, said polymer and said polar cosolvent.

11. A method according to claim 9 wherein said unsaturated hydrocarbon polymer is selected from the group consisting of ethylene propylene terpolymers, ethylene propylene copolymers, polyisoprene, Butyl, rubber, polybutadiene, and styrene-butadiene and styrene-isoprene random and block copolymers, poly-propylenes and polyisobutylenes, as well as plastic polypropylene copolymers or polyethylene copolymers.

12 A method according to claim 10 wherein the sulfonic acid groups of the sulfomaleic anhydride adduct with the unsaturated hydrocarbon polymer are neutralized with a metal counterion selected from the group consisting of iron, aluminum, lead and Groups IA, IIA, IB and IIB of the Periodic Table of Elements.

13. A method according to claim 9 wherein the sulfonic acid groups of the sulfomaleic anhydride adduct with the unsaturated hydrocarbon polymer is neutralized with ammonia or an organic amine.

14. The method of claim 9 wherein said poly-mer is incorporated into said organic liquid at a level of from .01 to 20 grams/100 ml.

15. The method of claim 9 wherein said organic liquid has a viscosity at 100°F of less than 35 centipoises.

16. The method of claim 9 wherein said organic liquid is a lubricating oil.

17. The method of claim 9 wherein said polar cosolvent is selected from the group consisting of alcohols and amines.