CA2025587A1 - Poly(keto-esters) - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE Novel poly(keto-esrters) having pendant functionality comprised of carbonyl and oxycarbonyl units randomly combined with linking units derived from olefinic monomers to form an essentially straight-chain polymer backbone are provided. The poly(keto-esters) having pendant functionality are produced by converting a portion of the carbonyl functionality of a polyketone to oxycarbonyl groups. The conversion is achieved by reacting the polyketone with an organic peroxyacid in an inert liquid medium at a temperature from -20°C. to 150°C.

Description

POLY(I~ETO-ESTERS) The present inv~ntion relates to a new class of useful poly(keto-esters) having pendant functionality and con~aininc~ carbonyl groups and oxycarbonyl groups in the polymer chain and the method for preparing same.
Poly~:etones, i.e., polymers having carbonyl groups incorporated in the polymer chain, are known and are most co~monly produced by polymerizing carbon monoxide with one or more a-olefins. Polyketones of -this type derived ~rom ethylene and carbon monoxide are disclosed by Brubaker in U.S. Patent No. 2,495,286. Numerous other liquid and gas phase procedures utilizing Ziegler and radical catalysts have been descr~bed in the prior art for polymerizin~ carbon monoxide with ethylene and other olefinically unsaturated monomers. A general review of the properties, preparations, reactions and uses of olefin-carbon monoxide copolymers can be found in the Encyclopedia of Polymer Science and Technology, Vol. 9, p. 397-402, John Wiley & Sons, Inc.
~ lg68 ) .
Carbon monoxide is also known to be copolymeriz-able with a variety of functionaliæed vinyl monomers to produce polyketones having pendant functional groups.
For example, copolymers of carbon monoxide with vinyl halides, most commonly vinyl chloride, is reported by Westcott, et al. in Macromolecules 17, 2501 ~1984~, Kawai, et al. in J. Polym. Sci., A-1 10, 1709 ~1972) Weintraub, et al. in Chem. Ind. 1976 (1965) and in U.S. Patent No.
3,790,460; The copolymerization of carbon monoxide wi~h styrene and vinyl chloride is disclosed by Kawai, et al.

-2~

in J. Polym. Sci., Polym. Chem. Ed. 12,1041 (1974). Methyl l methacrylate, acrylonitrile, vinyl chloride, vinylidene chloride and styrene have also been copolymerized with carbon monoxide using azobisisobutyronitrile catalyst by Otsuka, et al. in ~ie Makromolekulare Chemie 103, 291 (1967). Terpolymers of carbon monoxide, ethylene and vinyl acetate are similarly disclosed in U.S. Patent Nos.
4,172,939, 4,137,382 and 3,780,140. Additionally, in U.S.
Patent No. 3,780,140 the terpolymerization of ethylene and carbon monoxide with methyl methacrylate, vinyl proprionate, methyl vinyl ether and isobutyl acrylate is described.
European Patent Application EP 281139A2 discloses terpolymers of ethylene, carbon monoxide and maleic anhydride.
Various procedures are known ~or the chemical modification of polyketones. U.S. Patent No. 2,457,271 discloses a method for modifying monoolefin-carbon monoxide copolymers to increase the degree of unsaturation by heating the copolymer in a solution of an organic solvent with a minor amount of an alkali metal hydroxide. The copolymer is reacted until the oxygen content is decreased by at least 5%
or the iodine number increased to at least 25. Modification of polyketones (monoolefin-carbon monoxide copolymers) by reaction with hydrazine hydrate and related nitrogen containing compounds is described in U.S. Patent No.
2,457,279. A process for reacting polyketones with hydrogen cyanide to prepare polycyanohydrin resins is disclosed in U.S. Patent No. 2,495,284.
U.S. Patent No. 2,495,292 discloses the catalytic hydrogenation of monoolefin-carbon monoxide polymers in the 3 presence of a nickel catalyst to reduce the carbonyl groups to secondary alcohol groups and obtain high molecular weight 3 .~

polyhydric alcohols. U.S. Patent No. 2,846,406 relates to a 1 process for reacting monoolefin-carbon monoxide copolymers with formaldehyde and specific ammonium or amine salts to produce polyamines of relatively high molecular weight.
Another process for modifying monolefin-carbon monoxide copolymers by reaction with hydrazoic acid in the presence of an acid catalyst is disclosed in U.S. Patent No.
3,068,201.
Processes for producing thermoplastic polymers from polyketones are also disclosed in U.S. Patent Nos.
3,979,373 and 3,979,374. The products of U.S. Patent No.
3,979,373 are polymeric furan derivatives obtained by reacting an equimolar alternate copolymer of ethylene and carbon monoxide with a strong acid, e.g., sulfuric, phosphoric, p-toluene sulfonic, etc., at 40-200C. The polymeric pyrrolic polymers of U.S. Patent No. 3,979,374 are obtained by reacting an equimolar alternate copolymer of ethylene and carbon monoxide with a primary monoamine in the presence of strong acid and a solvent at a temperature from 40-lOO~C.
U.S. Patent Nos. 4,616,072 and 4 t 687,805 disclose halogenating ethylene-carbon monoxide copolymers by 1 contacting said copolymers in a liquid medium and in the presence of an anionic halogenation catalyst selected from Lewis acids and Lewis bases.
The oxidation and chain cleavage of ethylene-carbon monoxide copolymers to produce mixtures of a, dicarboxylic acids ranging from succinic acid through dodecanedioic acid and possibly higher and their corresponding esters is disclosed in U.S. Patent No.
2,436,269. The oxidation is typically accomplished utilizing nitric acid and a vanadium oxidation catalyst, e.g., vanadium pentoxide or ammonium vanadate. Other oxidizing agents which are disclosed include the higher oxides of nitrogen, chromic acid, permanganates, molecular oxygen or air, or mixtures of these.
It would be highly advantageous if a process were available whereby carbonyl groups incorporated in a polymer chain having pendant functional groups, such as in several of the above-described polyketones, could be readily oxidized to ester groups. It would be even more advantageous if this conversion could be accomplished without significant cleava~e of the polymer chain, i.e., without substantially altering the molecular weight and molecular weight distribution of the polymer, and wit~out affecting other functionality present in the polymer. It would be still more advantageous if the degree of oxidation could be easily controlled so that substantially all or only a portion of the carbonyl groups could be converted to oxycarbonyl moieites. These and other advantages are realized by the process and resultant polymers ~f the 3 present invention and will be described in more detail to ~ollow.

~' ` '' ' " ' ' ' ~ ~ ' ~ f j lhe ~resent invention relates to a poly(keto-1 ester) ha~ing a pendant functionality and a molecular weight greater than 1000 comprised of (a) carbonyl units; (b) oxycarbonyl units; ~c) lin~ing units derived from olefinic monomers and corresponding to the formula:

Il 13 - - C - C

wherei.n at least one of R1, R2, R3 and R4 is a functional group containing one or more oxygen, nitrogen, sulfur or halogen atom and the remaining R groups are hydrogen, alkyl or aryl, said units randomly arranged to form an essentially straight-chain polymer backbone with (a) and (b) constituting from 0.1 to 50 mole percent o~ the polymer, and the molar ratio of (a) and (b) ranging from 0.01 to 100:1. -Also, the present invention relates to a process ~or converting polyketones having pendant functionality to polyesters comprising contacting a polyketone having a molecular weight greater than 1,000 and containing 0.01 to 50 mole percent carbonyl group and wherein the pendant functional groups contain one or more oxygen, nitrogen, sulfur or halogen atoms or a combination of said atoms with an organic peroxyacid oxidizing agent having from 2 to 30 carbon atoms in an inert liquid medium at a temperature from -20C. to 150C.; the molar ratio of said oxidizing agent to carbonyl ranging from 0.01:1 to 3001 and the weight ratio of said inert liquid medium to said polyketone ranging from 1:1 to 100:1.
The process involves contacting a polyketone of molecular weight greater than 1,000 and containing from O.U1 to 50 mole perc~nt carbonyl with an organic peroxyacid :

~6~

oxidizing agent having from 2 to 30 carbon atoms in an inert l liquid medium at a temperature from -20C. to 150C. The molar ratio of organic peroxyacid to carbonyl can range from Q.1:1 to 30:1 and the wcight ratio of the inert liquid medium to polyketone can range from 1:1 to 100:1.
Substantially all or only a portion of the carbonyl group present in the poly~etone backborle can be converted to ester moieties.
Polyketones oxidized in accordance with the present procedure are typically obtained by polymerizing carbon monoxide with a vinyl or vinylidene monomer. Useful vinyl or vinylidene monomers, generically referred to herein as the functionalized comonomer, correspond to the ~ormula H2C = CRlR2 where Rl represents the functional group and R2 is hydrogen, al~yl, aryl or a second ~unctional group which can be the same or different than Rl. Useful ~unctional groups contain one ore more oxygen, nitro~en, sulfur or halogen atoms or a combination thereof. In one embodiment of the invention, polyketones which are terpolymers obtained by polymerizing carbon monoxide with a functionalized comonomer and an a-olefin are oxidized.
In a particularly useful embodiment of the invention, the polyketone will have a molecular weight from about 10,000 to 1,000,000 and the carbony~ content will range from 0.5 to 20 mole percent. Organic peroxyacids which are especially useful oxidizing agent include chloro-, fluoro-, and carboxy--substituted aromatic or aliphatic peroxyacids. These peroxyacids are particularly effective for the process when employed at molar ratios from 2:1 to 15:1 (peroxyacid:carbonyl). The process is highly useful for the conversion of ethylene-vinyl acetate-carbon monoxide terpolymers to the corresponding polyesters.

, - ~3 As employed herein, the term polyketone qenerally 1 refers to polymers having a plurality oE carbonyl( O )groups in the polymer chain. The carbonyl groups, also referred to herein as ketone or keto groups, may be randomly or uniformly distributed throughout the polymer chain.
The ter~ polyester is used herein in a generic sense and encompasses any polymer having one or more oxycarbonyl( 11 ) groups in the polymer chain. The polyesters will typically contain a plurality of oxycarbonyl groups, also referred to herein as ester groups;
however less than all of the available car~onyl functionality of the polyketone may be converted to oxycarbonyl. In the latter case, the resulting polyesters will contain both carbonyl groups and these polyesters are sometimes referred to herein as poly~keto-esters).
As will be apparent to those skilled in the art, a broad array of useful polyester products, including poly~keto-esters), having functional groups pendant to the ~ polymer backbone can be produced by the present process. It is a highly desirable aspect of the present invention that by judicious selection of the polyketone and the process variables, it is possible to vary the composition of the resulting product with respect to the amount of carbonyl and oxycarbonyl groups present therein thus making it possible to "tailor" products to pre-determined specifications and for speci~ic applications.

3o Considering thc reaction of only a single carbonyl 1 group wlthin a polyketone molecule derived from the copolymerization of carbon monoxide with a functionalized comonomer, the process of the present invention can be represented as follows:

H2cRlR2~ C } ~CH2CRlR2~ CO

or ~CH2CRlR2~ OC -~

where R1 represents a functional group, R2 represents hydrogen alkyl, aryl or a functional group, and x is an integer representing the number of adjoining comonomer units at a particular C0 site. It is evident fxom the above-equation that insertion of the oxygen atom can occur on either side of the carbonyl group.
While it is possible to obtain quantitative conversion of the carobnyl to oxycarbonyl groups, it is not necessary. Substantial amounts of carbonyl functionality may remain and be present in the resulting polyester product. For example, if the above-depicted reaction sequence is adapted to a functionalized polyketone where only a portion of the carbonyl groups in the polyketone produced by the copolymerization of carbon monoxide with a functionalized comonomer is reacted, the reaction showing 3 one possible molecular configuration which could result can be represented as follows:

',~

~g_ ~' ',;, ','i' \ ~CH~CRlR2t~ C ~CH2 \ 0 ~CH2CRlR2~ Co~cH2cRlR2~ ~

where R1 and R2 are the same as previously defined and x and y are integers, which can be the same or different, representing the number of repeating functionalized comonomer units.
The polyketone polymers utilized for the preparation of the polyesters ln accordance with the process of the present invention comprise a hydrocarbon polymer chain backbone having a plurality of carbonyl groups distributed throughout with the carbon atom of the carbonyl group being part of the polymer chain backbone. The polymer chain backbone is comprised substantially entirely of carbon atoms. Without regard to any functional groups pendant to the polymer chain backbone, the carbonyl groups may be either randomly or uniformly distributed within the polymer molecule, i.e., along the polymer backbone. The polyketones can structurally be represented as being comprised of repeating units of the structural formula:

R-C

3 where R represents a bivalent functionalized hydrocarbon moiety.

, ~ 10- 2: f The molecular ~eight of the polyketones can range from 1 about 1,000 up to several million or more. It is possible to react extremely high molecular weight polyketones (up to about 5 million) in accordance with the process to convert all or a portion of the carbonyl ~roups to ester moieties. Most commonly, the polyketones will have molecular weights from 1,000 to 2,000,000 and, more particularly, from a~out 10,000 up to about 1,000,000. The carbonyl contentr expressed in mole percent, of the polyketones will range from 0.01 up to about 50. Most usually the carbonyl content will range from 0.5 mole percent up to about 20 mole percentO
Useful polyketones can be obtained by any of the known procedures described in the art. The method of prepartion of the polyketones plays no role in the process of the invention so long as the polyketone is substantially free of impurities, such as catalyst residues or the like, which might interfere with the oxidation reaction. While the polyketones are most advantageously prepared by copolymerization, other procedures can be utilized. These can include, for example, copolymerization of ethylene with aliphatic aldehydes at high temperature and pressure;
oxidation o~ polyvinylalcohol or polyethylene; cationlc polymerization of ketenes or diketenes; radical ring-opening polymerization of unsaturated cyclic esters of diketenes;
radical ring-opening polymerization of 2,2-diphenyl-4-methylene-1,3- dioxolane, and the like.
Copo]ymerization of carbon monoxide and a-olefins or mixtures of a-olefins is commonly utilized to pro~uce the polyketones. Numerous procedures for preparation ~f these polymers are known and described in the prior art. The a-olefins 3 which are used typicall~ have from 2 to 12 carbon atoms and include aliphatic a-ole~ins, such as ethylene, propylene, butene-l, isobutylene, hexene-l, octene-l, and a-ole~ins having l aromatic substituents, such as styrene, p-methyl styrene, ~-methylstyrene and the like. Polyketones obtained by the polymerization o~ carbon monoxide and ethylene or the polymerization of carbon monoYide, ethylene and a second a-olefin having from 3 to 8 carbon atoms, particularly propylene, are advantageously utilized ir, the present process.
The process of the present invention may also be advantageously used with other polymers having carbonyl groups present in the polymer chain and derived from one or more olefinically unsaturated monomers such as styrene;
a-methylstyrene, ~-olefins; acrylonitrile; acrylamide; vinyl chlo~ide; vinylidene chloride; vinyl acetate; methyl vinyl ketone; vinylpyridine; acrylic acid and esters thereof;
methacrylic acid and esters thereof; maleic anhydride and mono-diesters thereof; and the like.
Polyketones having functional groups pendant to the polymer backbone are similarly generally obtained by copolymerizing carbon monoxide with the functionalized comonomer. Useful functionalized comonomers for this purpose include vinyl and vinylidene monomers corresponding to the general formula H2C = CRlR2 where Rl represents a functional group containing one or more oxygen, nitrogen, sulfur or halogen atoms or a combination of two or more of these atoms, and R2 is hydrogen, alkyl, aryl, or a functional group as defined for Rl. The functional groups Rl and R2 can be a single atom, 3 as in the case of halogen, or a su~stituted aliphatic or aromatic or hetrocyclic moiety. When the -functional group is a single halogen atom, it is most commonly chlorine.
When both Rl and R2 are functional groups, they can be the same or different.

12 ,~ ; ~ i Representativc functional groups include alkoxy;
1 aryloxy; acyl; acyloxy; carboxy and derivatives thereof including salts, esters and amides; nitrile; amine; halo; thioal~yl;
pyridyl; pyrrol; furfuryl; furoyl; thia201yl; thienyl; and the like. Monomers which can be copolymerized with carban monoxide to introduce functional groups of the above types include vinyl acetate; vinylacetronitrile; vinyl n-butyl ether; vinyl butyrate;
vinyl chloride; vinylidene chloride; acrylonitrile; methyl vinyl ketone; methyl vinyl ether; vinyl isobutyl ether; vinyl pyridine;
N-vinylcarbazole; vinyl 2-chloroethyl ether; vinyl 2-ethylhexanoate; vinyl 2-ethylhexyl ether; maleic anhydride, vinyl fluoride, acrylic acid; methacrylic acid; ethyl acrylate;
methyl methacrylate; and the li~e. It should be noted that when the functional group is a ketone, as with methyl vinyl ketone, in addition to oxidizing carbonyl groups present in the polymer chain, all or a portion of the carbonyls of the pendant keto groups will also ~e oxidized to oxycarbonyl groups.
Particularly useful polyketones employed in the present process are obtained when the functionalized comonomer is selected fxom the group consisting of acrylic acid, Cl 4 alkyl esters of acrylic acid, methacrylic acid, Cl 4 alkyl esters of methacrylic acid and vinyl Cl 4-alkanoates. It is even more advantageous if the functionalized comonomer is vinyl acetate, vinyl butyrate, or iso-butyl acrylate.
The functionaliæed comonomer may be the sole comonomer emplo~ed with the carbon monoxide or it may be advantageously polymerized with the carbon monoxide in a mixture of comonomers wherein the mixture is comprised of a functionalized comonomer 3 and an a-olefin of the type described aboYe, i.e., C2 12 a-olefin. Terpolymers are produced in this manner. Particularly -13~ s~, use~ul polyketone terpolymers containing pendant functional l groups are obtained by copolymerizing carbon monoxide with ethylene and a functionalized comonomer selected from the group consisting of acrylic acid, Cl 14 al~yl esters of acrylic acid, methacrylic acid, C1 14 alkyl esters of methacrylic acid and vinyl Cl 14- alkanoates. When utilizing a terpolymer the amount of carbon monoxide polymerized will be the same as previously described and the balance will be comprised of the functionalized comonomer and the a-olefin present in a molar ratio from 50:1 to 1:50 and, more preferably, 10:1 to 1:10.
Polyketones which can be oxidized in accordance with the present invention and obtained by polymerizing carbon monoxide with ~unctionalized comonomers, alone or in combination with a-olefins, are known and some of these polymers are commercially available. For example, terpolymers of ethylene, carbon monoxide and vinyl acetate are available under the trademark ELVALOY. Copolymers of carbon monoxide and vinyl halides, such as vinyl chloride, can be obtained by the polymerization procedures described in U.S. Patent No. 3,790,460 and by Wescott, et al., Macromolecules 17, 2501 (1984), Kawai, et al., J. Polvm. sci., A-1 10, 1709 ~1972), Weintraub, et al., Chem. Ind. 1976 (1965). Copolymers of carbon monoxide with styrene or vinyl chloride can be produced in accordance with the procedures of Kawai, et al., J. Polym. Sci., Polym. Chem. Ed. 12, 1041 (1974). Carbon mono~ide can also be copolymerized with methyl methacrylate, acrylonitrile, vinyl chloride, vinylidene chloride or styrene using azobisisobutyronitrile catalyst as described by Otsuka, et al. in Die Makromolekulare Chemie 103, 291 (1967). The procedures of U.S. Patent Nos. 4,172,939, 3 4,137,382 and 3,780,140 can be employed to produce terpolymers of carbon monoxide, ethylene and vinyl acetate and terpolymers of carbon monoxide and ethylene with methyl methacrylate, vinyl propionate, methyl vinyl ether or isobutyl acrylate can be obtained in acco~dance with the procedure of U.S. Patent No.
l 3,780,140.
Physical characteristics of the resulting polyest~rs esters are a function of molecular weight and the molecular weight distribution of the polyketone employed and the extent of conversion of carbonyl groups to oxycarbonyl groups. These, in turn, primarily depend on the composition of the polyketone, reaction conditions, and amount of oxidizing agent used.
For the process of this invention, the reaction is carried out in an inert liquid medium, that is, a material which is a li~uid at the reaction temperature and which does not react with either the polyketone or the polyester and which is not oxidized under the reaction conditions.
Additionally, the liquid must be one which is capable of either dissolving or swelling the polymer. While the boiling point of the liquid medium is not critical, the boiling point should not be so high as to make removal of the solvent difficult. The reaction can be run under reflux conditions or in a pressure vessel.
Vseful mediums for the reaction include hydrocarbons, chlorinated hydrocarbons, nitrohydrocarbons, carboxylic acids and carboxylic acid esters. Hexane, heptane, octane, benezene, decalin, methylene chloride, chlorobenzene, dichlorobenzene, nitrobenzene and dimethylphthalate are illustrative of the compounds which can be used as the reaction medium for the process. Aliphatic (C5 10) hydrocarbons, benzene, chlorinated C1 3 aliphatic hydrocarbons, chlorobenzene and dichlorobenzene are particularly advantageous for the process.
The weight ratio of the liquid medium to polyketone can 3 vary over broad limits and generally ranges from 1:1 to 100:1.
More preferably the weight ratio of liquid to polyketone will range from 5:1 up to about 50:1.

-15- ~ J ~ ~

An oxidizing agen-t is necessarily utilized for the 1 process and is dispersed or dissolved in the inert liquid medium and contacted with the poly~etone. The molar ra-tio of oxidizing agent to carbonyl group ranges from about 0.1:1 to 30:1 and, most preferably, from 2:1 to 15:1. Organic peroxyacids are employed as the oxidizing agent for the present process. Useful organic peroxyacids for the invention contain from 2 up to about 30 carbon atoms and correspond to the formula:

R'-COOH

where R' is an aliphatic, cycloaliphatic or aromatic moiety which can be unsubstituted or substituted with one or more halo, nitro or carboxyl groups. When R' is aliphatic, i.e., an alkyl group, it will generally contain from 1 to 19 carbon atoms. When R' is cycloaliphatic, i.e., a cycloalkyl group, it will generally contain from 5 to 19 carbon atoms.
When R' is aromatic, i.e.~ an aryl group, it will generally contain from 6 to 19 carbon atoms.
As previously indicated, any of said alkyl, cycloalkyl or aryl groups can contain halo-, nitro-, or carboxyl-substituents. Chloro and fluoro groups are particularly advantageous halo substituents. In a particularly useful embodiment, the organic peroxyacid oxidizing agent is a chloro-, fluoxo- or carboxyl-substituted aromatic or aliphatic peroxyacid.
Peroxybenzoic acid, m-chloroperoxybenzoic acid, peroxyacetic acid, tri~luoroperoxyacetic acid, monoperoxyphthalic acid and monoperoxymaleic acid are representative o~ the oxidi~ing agents 3 which can be used. m-Chloroperoxybenzoic acid and monoperoxy-maleic acid have been ~ound to be particularly advantageous. The ~6~

peroxyacid can be used as such, as formed in situ, e.g., by the l reaction of maleic anhydride with hydrogen peroxide.
The reaction can be conducted at temperatures from about -20~C. up to about 150~C.; however, it is generally considered most advantageous to carry out the reaction at a temperature ~rom about 20C. to 100C. While the reaction time will vary depending on the reactants and liquid medium used and the reaction temperature, it can range from 30 minutes under optimal or near optimal conditions up to 24 hours or more where low reaetion temperatures and/or low eoncentrations or reactants are used.
Reaction conditions and time o reaction will be selected based on the degree of conversion of carbonyl to oxycarbonyl desired. As previously pointed out, all or substantially all o~ the available carbonyl ~roups of the polyketone can be converted to ester moieties if desired.
However since it is not necessary to achieve 100% conversion and in certain instances is advantageous to produce poly(keto-esters), i.e., polymer products which contain both oxycarbonyl and carbonyl moieties, the process is generally conducted in such a way that only a portion of the keto funetionality is converted to ester groups. This permits the use of reaction times and conditlons which minimize or eompletely eliminate undesirable chain scission reaetions.
Most commonly the reaction is earried to no more than 9~%
eonversion of the ~eto groups.
The polymer produets prepared in aecordanee with the invention, whether they contain only oxyear~onyl moieties or both carbonyl and oxyearbonyl groups, are reeovered utilizing eonventional proeedures known to the 3 art. Generally, the polymer solution or polymer dispersion is eooled to ambient eonditions to preeipitate the polymer whieh is then reeovered by filtration. To facilitate this precipitation, p~ecipitating diluents which are non-solvents l for the polyester, i.e., do not dissolve or swell the polymer, can be added. Such precipitating diluents include, but are not limited to, methanol, ethanol, propanol, t-butanol, acetone and the like. Since excess oxidizing agent and by-products Eormed as a result of the reaction, e.g., carboxylic acids, may be precipitated with the polyester it may be advantageous to re-dissolve the polymer in a solvent, such as toluene or xylene, and re-precipitate by the addition of one or more of the aforementioned precipitating diluents.
The recovered polymer is then dried and, if desired, additives incorporated therein.
It is }nown that the subtrate polyketones, particularly ethylene-carbon monoxide copolymers, are known to exhibit photodegradability due to absorption of radiation by the carbonyl chromophore (Comprehensive Polymer Science, Vol. 6, p. 530, Pergamon Press), however, the polyester products obtained according to the present process which result from the partial conversion of carbonyl to oxycarbonyl moieties are both photodegradable and biodegradable. This is a particularly useful combination of properties.
The biodegradable polyesters obtained in accordance with the present process are highly usefu~ as plastics and waxes, the degree of biodegradability increasing with increasing percent conversion of main-chain carbonyl groups to oxycarbonyl moieties. The present products are also useful as adhesives and coatings.
The following examples illustrate the invention more fully, however, they are not intended as a limitation 3 on the scope thereo~. In the examples, all parts, percentages and ratios are on a weight basis unless otherwise indicated.

-18~

l Ten grams of a polyketone lethylene-carbon monoxide (ECO) copolymer resin powder contalning 1.6% carbon monoxide (1.6 mole %) carbon monoxide (Mw 125,000; ~n 18,000) and 2.0 grams m-chloroperoxybenzoic acid (MCPBA) were charged to ~lask containing 50 mls heptane and dissolved therein. The ratio of heptane to polyketone was 3.~:1 and the molar ratio of the oxidizing agent to carbonyl (CO) was 2.1:1. The reaction mixture was stirred for 2 hours at 80OC. and then cooled to room temperature.
Methanol (250 mls) was added to precipitate the polymer.
The polymer was recovered by filtration, washed with methanol and dried at room temperature under vacuum.
Analysis of the resulting product by infrared spectroscopy showed a strong absorption at 1735 cm 1 attributable to the presence of ester carbonyl. The infrared spectrum also showed a significant decrease in the ketone carbonyl absorption at 1710 cm 1 compared to the starting polyketone.
Based on the relative heights of the infrared absorption peaks, conversion of carbonyl to oxycarbonyl was calculated to be 90~. Ester formatlon was also confirmed by nuclear magnetic resonance spectroscopy.

EXAMPLE I I
1 The procedure of Example I was repeated on a larger scale. Reactants used were the same except that the ratio of heptane to ECO copolymer was 2.4:1 and the molar ratio of m- chloroperoxybenzoic acid to carbonyl was 2.0:1.
After 2 hours reaction at 80C. approximately 80% of the carbonyl groups of the polyketone were converted to oxycarbonyl groups. The resulting polyester product ~tensile strength at yield 1650 psi, elongation 540% was useful for the preparation of sheet, film and molded articles.

, ;

s ~

EXAMPLES I I I -VJ I I
1 To further demonstrate the ability to vary the process, a series of reactions were conducted following the general procedure of Example I. Process details and results were obtained, i.e., degree of conversion carbonyl to oxycarbonyl, are set forth in Table I. It is apparent from the data that a variety of solvent and conditions can be utilized for the oxidation reaction and that a wide variety of polyester products can be produced.

1.0 ~ ! ", ~

C <: C < H H Wl H H H <~ H ~C
H H H

(D

w ~ o co ~ co co oo ~ ~_ .. .. .. .. .. .P ~ p.
~ It oPJ

w --~3 --n _ 3 n 5 (D o P~ o~ ~J ~ o ~--- o f~
n~ t~
n --~D r~
~ tt N ..
r~ PJ n ,t ~ w n3 ~D n o rD ~3 ~ ~d ~
o o o o o o (D r 3 ~
~n H
o o o 1~
~ pJ
.. tD n _~ rt.

Ul w u~ co n o o o ul o o o o 0\o _ o ..

EXAMPLE IX
1 A low molecular weight polyketone was oxidized using monoperoxymaleic acid. The monoperoxymaleic acid was prepared by reacting (1 houx at ~0C. with stirring) 26 mls 30% aqueous hydrogen peroxide with 56.0 grams maleic anhydride in 125 mls methylene chloride. The solid maleic acid formed was collected on a filter and the filtrate containing monoperoxymaleic acid was added to a chlorobenzene solution of the polyketone. The solutlon was obtained by dissolving 5.0 grams ethylene carbon monoxide copolymer [powder; 36.6 wt. % ~36.6 mole %) carbon monoxide; Mw 3,700; Mn 1,970] in 100 mls chlorobenzene. After stirring for 24 hours at 70C., the mixture was cooled and filtered and 500 mls methanol added to the filtrate to precipitate the polyester. After washing with methanol, the polyester was dissolved in toluene and re-precipitated usin~ methanol. Conversion of keto functionality to ester functionality was calculated to be 20% based on a comparison of the relative intensities of the infrared absorption peaks.

EXAMPLES X-XI I I
1 A series of low molecular weight ethylene-carbon monoxide IECO) copolymers of varying carbonyl content were oxidized to the corresponding polyesters in accordance with the general procedure of the invention. In each instance 90~ of the carbonyl functionality was converted to oxycarbonyl groups. The oxidizing agent used was m-chloroperoxybenzoic acid ~MCPBA) acid and the dilu~nt was chlorobenzene. Characteristics of the EC0 copolymers and and reaction particulars are set forth in Table II.

x ~c x x w ~. ~
~ ~ o ~
o o o o , Y ~ ~ 1~
~' w ~ ~ ~
o o o o ~w~
. o u~ w w r~
O ~D ~ O o\o w ~-- ~:
o . ~ o ~D ~ IJ
O O (\Do o ~ ~t .. .. .. .. W ~-~
Y o ~ ~3 O w ~J tJ H
O ~

~1 ~I ~I ~1 ~
,, o o o o o tD
O---o a~ ~ ~ ~t 3 P~
u~ (D n ~ ' EXAMPLE XIV
l Ethylene-carboll monoxide copolymer pellets [1.6 wt. % (1.6 mole %) carbon monoY~ide; Mw 125,000; Mn 18,000] were suspended in 10 mls chlorobenzene with l.6 grams m-chloroperoxybenzoic acid in a glass vessel. The molar ratio of oxidizing agent to carbonyl was 8.3:1 and the ratio of solvent to copolymer resin was 5.9:1. The container was sealed and rolled for 90 hours on a roller mill under ambient conditions. The swelled polymer pellet (recovered by filtration) were washed with toluene and then methanol and purified by dissolving in toluene followed by precipitation with methanol. Infrared analysis of the dried polymer product showed a strong ester carbonyl absorption at 1735 cm 1 Based on the relative in-tensities of the keto and ester peaks the conversion of ketone to ester functionality was calculated to be 35%.

EXAMPLE XV
l Ethylene-carbon monoxide copolymer powder [1.6 wt.% (1.6 mole%) carbon monoxide; Mw 125,000; Mn 18,000]
was combined with chlorobenzene (weight ratio 7.7:1) and m-chloroperoxybenzoic acid (molar ratio 8.8:1l and stirred for 7 days at room temperature. Approximately fifty percent of the ketone groups of the polyketone converted to ester groups~ Expressed in different terms, the resulting polyester product had carbonyl and oxycarbonyl groups, present in essentially a 1:1 molar ratio, randomly distributed throughout the polymer chain.

3o --2 7-- ~ - r ~XAMPLE XVI
1 one gram of the polyketone of Example XV was dissolved in 25 mls chlorobenzene by heating at 90C.
The solution was cooled to 65C. and 3.0 grams maleic anhydride and 2.0 grams 30% a~ueous hydrogen peroxide added thereto. The reacti.on mixture was maintained at 65~C. for 21 hours with stirring after which time the polymer was precipitated by cooling the mixture and the addition of 50 mls. methanol. The recovered polymer was dissolved in 50 mls. toluene and re-precipitated using methanol. The infrared spectrum o~ the dried polymer showed the presence of an ester peak at 173S cm 1; the conversion of carbonyl to oxycarbonyl was calculated to be 2~%.

~8- " , ; '7 EXAMPLE XVII
1 To demonstrate the ability of the process to oxidize polyketones containing functional groups, a commercially available ethylene-vinyl acetate-carbon monoxide tcrpolymer sold under the trademark ELVALOY was reacted in accordance with the general procedures. The terpolymer contained 9.5 mole % vinyl acetate and 12.1 mole ~ carbon monoxide by analysis. For the reaction, 1.0 gram of the terpolymer was dissolved in 15 mls chlorobenzene at 90~C. The solution was then cooled to 65C. and 3.0 grams m-chloroperoxybenzoic acid (55%
purity) added thereto. The mixture was stirred at 65C.
for 20 hours after which time the solution was cooled to room temperature and 100 mls methanol added to precipitate the polymer product. The polymer was recovered by filtration, reprecipitated from toluene and dried at room temperature. Analysis of the recovered product by nuclear magnetic resonance spectroscopy indicated that 99% conversion of carbonyl to oxycarbonyl was achieved.

..

Claims (23)

1. A poly(keto-ester) having pendant functionality and a molecular weight greater than 1000 comprised of:
(a) carbonyl units;
(b) oxycarbonyl units;
(c) linking units derived from olefinic monomers and corresponding to the formula wherein at least one of R1, R2 R3 and R4 is a functional group containing one or more oxygen, nitrogen, sulfur or halogen atoms and the remaining R groups are hydrogen, alkyl or aryl; said units randomly arranged to form an essentially straight-chain polymer backbone with (a) and (b) constituting from 0.1 to 50 mole percent of the polymer, and the molar ratio of (a) and (b) ranging from 0.01:1 to 100:1.

2. The polytketo-ester) of Claim 1 having a molecular weight from about 10,000 to 1,000,000 and containing at least 2 mole percent oxycarbonyl.

3. The poly(keto-ester) of Claim 1 or 2 wherein (a) and (b) constitute from about 0.5 to 20 mole percent of the polymer and the molar ratio of (a) to (b) ranges from 0.1 to 10.

4 The poly(keto-ester) of any one of Claims 1 to 3 wherein (c) is derived from a functionalized vinyl or vinylidene monomer of the formula H2C = CR1R2 where R1 represents a functional group containing one or more oxygen, nitrogen, sulfur or halogen atoms or a combination of two or more of these atoms, and R2 is hydrogen, alkyl, aryl or a functionalized group as defined for R1 or a mixture of the C2-C12 alpha olefin and the vinyl or vinylidene monomer.

5. The poly(keto-ester) of Claim 4 wherein the monomer is polymerized with carbon monoxide to provide the polyketone.

6. The poly(keto-ester) of Claim 4 or 5 wherein the functionalized monomer is selected from acrylic acid, C1-4 alkyl esters of acrylic acid, methacrylic acid, C1-4 alkyl esters of methacrylic acid or vinyl C1-4-alkanoates.

7. The poly(keto-ester) of Claim 6 wherein the functionalized monomer is vinyl acetate, vinyl butyrate, or iso-butyl acrylate.

8. A process for converting polyketones having pendant functionality to polyesters comprising contacting a polyketone having a molecular weight greater than 1,000 and containing 0.01 to 50 mole percent carbonyl group and wherein the pendant functional groups contain one or more oxygen, nitrogen, sulfur or halogen atoms or a combination of said atoms with an organic peroxyacid oxidizing agent having from 2 to 30 carbon atoms in an inert liquid medium at temperature from -20°C. to 150°C.;
the molar ratio of said oxidizing agent to carbonyl ranging from 0.01:1 to 30:1 and the weight of said inert liquid medium to said polyketone ranging from 1:1 to 100:1.

9. The process of Claim 1 wherein substan-tially all of the carbonyl groups of the polyketone are converted to ester moieties.

10. The process of Claim 1 wherein only a portion of the carbonyl groups of the polyketone are converted to ester moieties.

11. The process of Claim 1 wherein the polyketone is obtained by the polymerization of carbon monoxide with a functionalized comonomer of the formula:
H2C = CR1R2 where R1 is a functional group containing one or more of oxygen, nitrogen, sulfur or halogen atoms or a combination of said atoms and R2 is hydrogen, alkyl, or a functional group as defined for R1 and which contains 0.5 to 20 mole percent carbonyl group.

12. The process of Claim 4 wherein the functionalized comonomer is selected from the group consisting of acrylic acid, C1-4 alkyl esters of acrylic acid, methacrylic acid, C1-4 alkyl esters of methacrylic acid and vinyl C1-4-alkanoates.

13. The process of claim 1 or 4 wherein the inert liquid medium is selected from hydrocarbons, chlorinated hydrocarbons, nitrohydrocarbons, carboxylic acids or esters of carboxylic acids.

14. The process of Claims 1, 4 or 13 wherein the organic peroxyacid oxidizing agent corresponds to the formula:
wherein R' is an alkyl group having from 1 to 19 carbon atoms; a cycloalkyl group having from 5 to 19 carbon atoms; an aryl group having from 6 to 19 carbon atoms; a halo-, nitro-, or carboxyl-substituted alkyl group having from 1 to 19 carbon atoms; a halo-, nitro- or carboxyl-substituted cycloalkyl group having from 5 to 19 carbon atoms; a halo-, nitro, or carboxyl-substituted aryl group having from 6 to 19 carbon atoms.

15. The process of Claim 14 wherein the organic peroxyacid is formed in situ.

16. The process of Claim 14 wherein the polyketone has a molecular weight from about 10,000 to about 1,000,000 and the functionalized comonomer is vinyl

17. Ihe process of Claim 16 wherein the reaction is carried out at a temperature from 20°C. to 100°C., the organic peroxyacid oxidizing agent is a chloro-, fluoro- or carboxyl-substituted aromatic or aliphatic peroxyacid, the molar ratio of the peroxyacid to carbonyl ranges from 2:1 to 15:1 and the weight ratio of inert liquid medium to polyketone is from 5:1 to 50:1.

18. The process of Claim 17 wherein the polyketone is a terpolymer obtained by copolymerizing carbon monoxide, the functionalized comonomer and a C2-12 alpha olefin.

19. The process of Claim 14 wherein the organic peroxyacid oxidizing agent is m-chloroperoxy-benzoic acid.

20. The process of Claim 14 wherein the organic peroxyacid oxidizing agent is peroxymaleic acid.

21. The proces of Claim 18 wherein the inert liquid medium is an aliphatic C5-10 hydrocarbon, a chlorinated C1-3 aliphatic hydrocarbon, benzene, chlorobenzene or dichlorobenzene.

22. The process of Claim 18 wherein the terpolymer is obtained by copolymerizing carbon monoxide, the functionalized comonomer and ethylene.

23. The process of Claim 22 wherein the functionalized comonomer is vinyl acetate.