Novel poly(keto-esters) having 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) 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.degree. C. to 150.degree. C.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a new class of useful polymers which 
contain both carbonyl groups and oxycarbonyl groups in the polymer chain. 
More specifically, the poly(keto-esters) of the invention have carbonyl 
and oxycarbonyl units randomly combined in a straight-chain arrangement 
with linking units derived from olefinic monomers. 
2. Description of Related Art 
Polyketones, i.e., polymers having carbonyl groups incorporated in the 
polymer chain, are known. They are most commonly produced by polymerizing 
carbon monoxide with one or more .alpha.-olefins. Polyketones of this type 
derived from ethylene and carbon monoxide are disclosed by Brubaker in 
U.S. Pat. No. 2,495,286. Numerous other liquid and gas phase procedures 
utilizing Ziegler and radical catalysts have been described in the prior 
art for polymerizing 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.(1968). 
Polyketones obtained by the copolymerization of carbon monoxide and 
functionalized vinyl monomers having pendant functional groups are also 
known. The copolymerization of carbon monoxide with vinyl halides, most 
commonly vinyl chloride, is reported by Wescott 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. Pat. No. 3,790,460; 
Kawai et al in J. Polym. Sci., Polym. Chem. Ed. 12, 1041 (1974) disclose 
the copolymerization of carbon monoxide with styrene and vinyl chloride 
Methyl methacrylate, acrylonitrile, vinyl chloride, vinylidene chloride 
and styrene have also been copolymerized with carbon monoxide using 
azobisisobutyronitrile catalyst by Otsuka et al in Die Makromolekulare 
Chemie 103, 291 (1967). Terpolymers of carbon monoxide, ethylene and vinyl 
acetate are disclosed in U.S. Pat. Nos. 4,172,939, 4,137,382 and 
3,780,140. Additionally, in U.S. Pat. No. 3,780,140 the terpolymerization 
of ethylene and carbon monoxide with methyl methacrylate, vinyl 
propionate, methyl vinyl ether and isobutyl acrylate is described European 
Patent Application EP 281139A2 discloses terpolymers of ethylene, carbon 
monoxide and maleic anhydride. 
Other methods are known for the preparation of polyketones and include, for 
example, copolymerization of ethylene with aliphatic aldehydes at high 
temperature and pressure; oxidation of polyvinylalcohol or polyethylene; 
cationic polymerization of ketene or diketene; radical ring-opening 
polymerization of unsaturated cyclic ethers or diketene; and radical 
ring-opening polymerization of 2,2-diphenyl-4-methylene-1,3-dioxolane. 
Various procedures are known to chemically modify polyketones. U.S. Pat. 
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. Pat. No. 2,457,279. A process for reacting polyketones with 
hydrogen cyanide to prepare polycyanohydrin resins is disclosed in U.S. 
Pat. No. 2,495,284. 
U.S. Pat. No. 2,495,292 discloses the catalytic hydrogenation of 
monoolefin-carbon monoxide polymers in the presence of a nickel catalyst 
to reduce the carbonyl groups to secondary alcohol groups and obtain high 
molecular weight polyhydric alcohols. U.S. Pat. No. 2,846,406 relates to a 
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 
monoolefin-carbon monoxide copolymers by reaction with hydrazoic acid in 
the presence of an acid catalyst is disclosed in U.S. Pat. No. 3,068,201. 
Processes for producing thermoplastic polymers from polyketones are also 
disclosed in U.S. Pat. Nos. 3,979,373 and 3,979,374. The products of U.S. 
Pat. 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.degree.-200.degree. C. The polymeric pyrrollic polymers of U.S. Pat. 
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.degree.-100.degree. C. 
U.S. Pat. Nos. 4,616,072 and 4,687,805 disclose halogenating 
ethylene-carbon monoxide copolymers by 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 .alpha., .omega.- dicarboxylic acids ranging from 
succinic acid through dodecanedioic acid and possibly higher and their 
corresponding esters is disclosed in U.S. Pat. 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. 
Poly(keto-esters) having ester groups pendant to the polymer chain are 
known and can be obtained by polymerizing carbon monoxide with alkyl 
acrylates or methacrylates as previously described. Optionally, other 
olefinic comonomers may be included in the polymerization. They can also 
be produced in accordance with the procedure of U.S. Pat. No. 2,557,256 by 
polymerizing carbon monoxide with a polymerizable olefinic compound 
containing ethylenic unsaturation and an alcohol or alkyl formate. 
Poly(keto-esters) having terminal ester groups are obtained by the 
palladium (II)-catalyzed copolymerization of carbon monoxide with ethylene 
in alcoholic solvents as disclosed by T. Lai et al in Organometallics, 3, 
866-870(1984). 
Poly(keto-esters) having keto and ester groups uniformly distributed 
throughout are also known. Such polymers can be produced by the 
ring-opening polymerization of unsaturated spiro ortho esters as disclosed 
by T. Endo et al in J. Polym. Sci: Polym. Chem. Ed., Vol 19, 1283 (1981). 
It is also known that numerous other poly(keto-esters) can be produced by 
the condensation polymerization of keto-dicarboxylic acids with diols. 
While the resulting condensation polymers will have both ester and keto 
groups in the polymer chain, the groups are necessarily fixed in relation 
to each other and uniformly located throughout the polymer backbone. 
Illustrative keto-containing diacids and diols which can be used include 
.gamma.-ketopimelic acid, .alpha.-oxoglutaric acid, oxalacetic acid, 
ethylene glycol, butanediol and hexanediol 
SUMMARY OF THE INVENTION 
The novel poly(keto-esters) of the present invention are obtained by 
converting carbonyl groups present in a polyketone to oxycarbonyl groups 
so that the resulting polymer will have both carbonyl and oxycarbonyl 
groups randomly distributed throughout the polymer backbone. More 
specifically, the poly(keto-esters) are comprised of (a) carbonyl units, 
(b) oxycarbonyl units and (c) linking units derived from olefinic 
monomers, said linking units (a), (b) and (c) oriented in a random fashion 
to form an essentially straight-chain polymer backbone. Units (a) and (b) 
are present in a molar ratio of 0.01:1 to 100:1 and the sum of these units 
constitutes 0.1 to 50 mole percent of the polymer. The poly(keto-esters) 
have molecular weights greater than 1,000. 
Olefinic monomers from which linking units (c) can be derived will 
correspond to the formula 
EQU R.sub.1 R.sub.2 C.dbd.CR.sub.3 R.sub.4 
where R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are independently selected 
from the group consisting of hydrogen, alkyl, aryl or a functional group 
containing one or more oxygen, nitrogen, sulfur or halogen atoms. The 
above-defined poly(keto-esters) are obtained by contacting a polyketone of 
molecular weight greater than 1,000 and containing from 0.01 to 50 mole 
percent carbonyl with an organic peroxyacid oxidizing agent having from 1 
to 20 carbon atoms in an inert liquid medium at a temperature from 
-20.degree. C. to 150.degree. C. The molar ratio of organic peroxyacid to 
carbonyl can range from 0.1:1 to 30:1 and the weight 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 polyketone backbone 
can be converted to ester moieties. 
Polyketones oxidized in accordance with the present procedure are typically 
obtained by polymerizing carbon monoxide with an ethylenically unsaturated 
monomer or mixture of one or more of these monomers. Useful monomers 
include C.sub.2-12 .alpha.-olefins and vinyl or vinylidene monomers, 
generically referred to herein as functionalized comonomers, corresponding 
to the formula 
EQU H.sub.2 C.dbd.CR'R" 
where R' represents the functional group and R" is hydrogen, alkyl, aryl, 
or a second functional group which can be the same or different than R'. 
Useful functional groups contain one or more oxygen, nitrogen, sulfur or 
halogen atoms or a combination thereof.

DETAILED DESCRIPTION OF THE INVENTION 
The present invention broadly relates to a process for converting carbonyl 
groups present in a polymer chain of a polyketone to oxycarbonyl groups 
and to novel polymers produced thereby. 
As employed herein the term polyketone generally refers to polymers having 
a plurality of carbonyl 
##STR1## 
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 term polyester is used herein in a generic sense and encompasses any 
polymer having one or more oxycarbonyl 
##STR2## 
in the polymer chain. The polyesters will typically contain a plurality of 
oxycarbonyl groups, also referred to herein as ester groups. Since less 
than all of the available carbonyl functionality of the polyketone is 
generally converted to oxycarbonyl, the resulting polyesters contain both 
oxycarbonyl and carbonyl groups and these polyesters are referred to as 
poly(keto-esters). 
As will be apparent to those skilled in the art, a broad array of useful 
poly(keto-esters) 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. This makes it possible to 
"tailor" products to pre-determined specifications or for particular 
applications. 
Considering the reaction of only a single carbonyl group within a 
polyketone derived from the copolymerization of ethylene and carbon 
monoxide, the process of the present invention can be represented as 
follows: 
##STR3## 
x and y are integers representing the number of comonomer units adjoining 
the particular CO site. It is evident from the above equation that 
insertion of the oxygen atom can occur on either side of the carbonyl 
group and different molecular species will result when x and y are 
different. It will also be obvious to those skilled in the art that an 
even greater number of possible molecular configurations are possible 
where a mixture of monomers, such as ethylene and vinyl acetate, is 
employed. 
While it is possible to quantitatively convert all of the carbonyl to 
oxycarbonyl groups, more typically only a portion of the carbonyl of the 
polyketone will be reacted. Substantial amounts of carbonyl functionality 
may remain in the resulting polymer product. For example, where only a 
portion of the carbonyl groups in functionalized polyketone produced by 
the copolymerization of carbon monoxide with a functionalized comonomer is 
reacted, one of the many possible molecular configurations which could 
result at adjacent carbonyl sites can be represented as follows: 
##STR4## 
where R' and R" will be later defined and x and y are integers, which can 
be the same or different, representing the number of repeating 
functionalized comonomer units. It will be evident that the number of 
possible arrangements of the repeating units within the polymer precludes 
formularization of the resulting poly(keto-esters). 
The polyketone polymers utilized for the preparation of the 
poly(keto-esters) in accordance with the process of the present invention 
have a hydrocarbon polymer chain backbone containing 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. 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 
##STR5## 
where R represents a bivalent moiety derived from an olefinic monomer or 
mixture of monomers. 
The molecular weight of the polyketones can range from 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 groups to ester moieties. Most 
commonly, the polyketones will have molecular weights from 1,000 to 
2,000,000 and, more particularly, from about 10,000 up to about 1,000,000. 
The carbonyl content, 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 percent. 
Useful polyketones can be obtained by any of the known procedures described 
in the art. The method by which the polyketones are prepared is of no 
consequence so long as the polyketone is substantially free of impurities, 
such as catalyst residues or the like, which might interfere with the 
oxidation of the carbonyl to oxycarbonyl. 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 of 
polyvinylalcohol or polyethylene; cationic polymerization of ketenes or 
diketenes; radical ring-opening polymerization of unsaturated cyclic 
ethers or diketenes; radical ring-opening polymerization of 
2,2-diphenyl-4-methylene-1,3-dioxolane, and the like. 
Copolymerization of carbon monoxide and .alpha.-olefins or mixtures of 
.alpha.-olefins is commonly utilized to produce the polyketones. Numerous 
procedures for preparation of these polymers are known and described in 
the prior art. The .alpha.-olefins which are used typically have from 2 to 
12 carbon atoms and include aliphatic .alpha.-olefins, such as ethylene, 
propylene, butene-1, isobutylene, hexene-1, octene-1, and .alpha.-olefins 
having aromatic substituents, such as styrene, p-methyl styrene, 
.alpha.-methyl styrene and the like. Polyketones obtained by the 
polymerization of carbon monoxide and ethylene or the polymerization of 
carbon monoxide, ethylene and a second .alpha.-olefin having from 3 to 8 
carbon atoms, particularly propylene, are advantageously utilized. One or 
more other olefinically unsaturated monomers such as styrene; 
.alpha.-methylstyrene; acrylonitrile; acrylamide; vinyl chloride; 
vinylidene chloride; vinyl acetate; methyl vinyl ketone; vinylpyridine; 
acrylic acid and esters thereof; methacrylic acid and esters thereof; 
maleic anhydride and mono- and diesters thereof; and the like may be 
included in the polymerization with the carbon monoxide and 
.alpha.-olefin. 
Polyketones having functional groups pendant to the polymer backbone can 
similarly be obtained by copolymerizing carbon monoxide with the 
functionalized comonomer. Useful functionalized comonomers for this 
purpose include vinyl and vinylidine monomers corresponding to the general 
formula 
EQU H.sub.2 C.dbd.CR'R" 
where R' 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 R" is hydrogen, alkyl, aryl, or a functional group as defined 
for R'. The functional groups R' and R" can be a single atom, as in the 
case of halogen, or a substituted aliphatic or aromatic or heterocyclic 
moiety. When the functional group is a single halogen atom, it is most 
commonly chlorine. When both R' and R" are functional groups, they can be 
the same or different. 
Representative functional groups include alkoxy; aryloxy; acyl; acyloxy; 
carboxy and derivatives thereof including salts, esters and amides; 
nitrile; amine; halo; thioalkyl; pyridyl; pyrroyl; furfuryl; furoyl; 
thiazoyl; thienyl; and the like. Monomers which can be copolymerized with 
carbon monoxide to introduce functional groups of the above types include 
vinyl acetate; vinylacetonitrile; 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 like. It 
should be noted that when the functional group is ketonic, 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 be oxidized to oxycarbonyl groups. 
Particularly useful functionalized comonomers are selected from the group 
consisting of acrylic acid, C.sub.1-4 alkyl esters of acrylic acid, 
methacrylic acid, C.sub.1-4 alkyl esters of methacrylic acid and vinyl 
C.sub.1-4 -alkanoates. It is even more advantageous if the functionalized 
comonomer is vinyl acetate, vinyl butyrate, or iso-butyl acrylate. 
The functionalized comonomer may be the sole comonomer employed 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 and an alpha-olefin of the type described above, 
i.e. C.sub.2-12 .alpha.-olefin. Terpolymers are produced in this manner. 
Particularly useful polyketone terpolymers containing pendant functional 
groups are obtained by copolymerizing carbon monoxide with ethylene and a 
functionalized comonomer selected from the group consisting of acrylic 
acid, C.sub.1-4 alkyl esters of acrylic acid, methacrylic acid, C.sub.1-4 
alkyl esters of methacrylic acid and vinyl C.sub.1-4 -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 .alpha.-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 functionalized 
comonomers, alone or in combination with .alpha.-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. Pat. No. 3,790,460 and by Wescott, et al 
Macromolecules 17, 2501 (1984), Kawai et al J. Polym. 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 monoxide 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. Pat. 
Nos. 4,172,939, 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 
accordance with the procedure of U.S. Pat. No. 3,780,140. 
Physical characteristics of the resulting poly(keto-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. The latter primarily depend on the composition of the 
polyketone, reaction conditions, and amount of oxidizing agent used. 
The reaction is carried out in an inert liquid medium, that is, a material 
which is a liquid at the reaction temperature and which does not react 
with either the polyketone or the resulting product 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. 
Useful mediums for the reaction include hydrocarbons, chlorinated 
hydrocarbons, nitrohydrocarbons, carboxylic acids and carboxylic acid 
esters. Hexane, heptane, octane, benzene, 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 (C.sub.5-10) hydrocarbons, benzene, chlorinated 
C.sub.1-3 aliphatic hydrocarbons, chlorobenzene and dichlorobenzene are 
particularly advantageous for the process. 
The weight ratio of the liquid medium to polyketone can 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. 
An oxidizing agent is necessarily utilized to convert the keto groups to 
ester moieties. The oxidizing agent is dispersed or dissolved in the inert 
liquid medium and contacted with the polyketone. The molar ratio 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 
##STR6## 
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-, fluoro- 
or carboxyl-substituted aromatic or aliphatic peroxyacid. Peroxybenzoic 
acid, m-chloroperoxybenzoic acid, peroxyacetic acid, trifluoroperoxyacetic 
acid, monoperoxyphthalic acid and monoperoxymaleic acid are representative 
of the oxidizing agents which can be used. m-Chloroperoxybenzoic acid and 
monoperoxymaleic acid have been found to be particularly advantageous. The 
peroxyacid can be used as such, or formed in situ, e.g., by the reaction 
of maleic anhydride with hydrogen peroxide. 
The reaction of the polyketone with the oxidizing agent can be conducted at 
temperatures from about -20.degree. C. up to about 150.degree. C.; 
however, it is generally considered most advantageous to carry out the 
reaction at a temperature from about 20.degree. C. to 100.degree. C. 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 
reaction temperatures and/or low concentrations of reactants are used. 
Reaction conditions and time of reaction will be selected based on the 
degree of conversion of carbonyl to oxycarbonyl desired. While all or 
substantially all of the available carbonyl groups of the polyketone can 
be converted to ester moieties it has been advantageous to convert only a 
portion of the carbonyl in order 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 functionality is converted to ester groups. This permits the use of 
reaction times and conditions which minimize or completely eliminate 
undesirable chain scission reactions. Most commonly the reaction is 
carried to no more than 90% conversion of the keto groups. In an 
especially useful embodiment, 20 to 80% of the carbonyl groups are 
converted to oxycarbonyl. 
The polymer products prepared in accordance with the invention are 
recovered utilizing conventional procedures known to the art. Generally, 
the polymer solution or polymer dispersion is cooled to ambient conditions 
to precipitate the polymer which is then recovered by filtration. To 
facilitate this precipitation, precipitating diluents which are 
non-solvents 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 formed 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. 
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, when the polyketones are converted to polyester products 
in accordance with the process of this invention by converting a portion 
of the carbonyl groups in the polymer chain to oxycarbonyl moieties, the 
resulting poly(keto-esters) can also be degraded by biological means, 
i.e., by the action of living organisms. 
In view of today's increased concern about disposal of plastic waste there 
is an increasing call for environmentally degradable polymeric materials 
and the combination of photoand biodegradability in a polymeric material 
is an extremely desirable characteristic. It is well-established that the 
substrate polyketones of this invention, particularly ethylene-carbon 
monoxide copolymers are photodegradable, due to the absorption of 
radiation by the carbonyl chromophore [Comprehensive Polymer Science, Vol. 
6, p530, Pergamon Press]. The conversion of polyketone carbonyl groups to 
oxycarbonyl groups can confer biodegradability on the polymer. As 
conversion increases, biodegradability increases. It is an added advantage 
that such poly(keto-esters) produced are intrinsically biodegradable. That 
is, they do not require the addition of biodegradable additives, such as 
starch. 
The poly(keto-esters) of the present invention which exhibit the 
aforementioned desirable characteristics are comprised of carbonyl units, 
oxycarbonyl units, and linking units derived from olefinic monomers. The 
units derived from olefinic monomers correspond to the formula 
##STR7## 
where R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently selected 
from the group consisting of hydrogen, alkyl, aryl or a functional group 
containing one or more oxygen, nitrogen, sulfur or halogen atoms. The 
units are linearly arranged in a random manner to comprise the polymer 
backbone. 
Randomness of the repeating units is a result of the oxidation process and 
the polyketones from which the poly(keto-esters) are derived. Since only a 
portion of the carbonyl groups are oxidized and the oxidation occurs in a 
more or less random fashion, non-uniform distribution of the repeating 
units within the poly(keto-ester) is insured. Furthermore, the carbonyl 
moieties being oxidized are randomly distributed in all but the situation 
where the polyketone is obtained by copolymerizing equimolar amounts of 
carbon monoxide and one other monomer. This random distribution of 
repeating carbonyl and oxycarbonyl units distinguishes the present 
poly(keto-esters) from heretofore known polyesters containing keto groups 
obtained by other processes where the carbonyl and oxycarbonyl groups in 
the polymer chain are fixed in relation to each other and uniformly 
located throughout the polymer backbone. 
The present poly(keto-esters) have molecular weights greater than 1,000. 
More typically, molecular weights range from 10,000 to 1,000,000. The 
molecular weight of the poly(keto-ester) may be essentially the same or 
different than the molecular weight of the starting polyketone. Since some 
chain scission generally occurs as a result of the oxidation, the 
molecular weight of the poly(keto-ester) is usually somewhat lower than 
that of the starting polyketone. Where the molecular weight of a 
polyketone is undesirably high, it is possible to produce 
poly(keto-esters) with molecular weights in a more useful range by 
controlling reaction conditions. 
The mole percentages of the carbonyl and oxycarbonyl groups, taken as a 
whole, will range from 0.1 up to 50 mole percent. Typically, the sum of 
the mole percentages of these two groups in the poly(keto-ester) is 
essentially the same as the mole percent of carbonyl in the starting 
polyketone but some minor variation may occur. Most generally the mole 
percent of carbonyl/oxycarbonyl in the poly(keto-ester) ranges from about 
0.5 to about 20. The molar ratio of carbonyl to oxycarbonyl can be widely 
varied but usually ranges from about 0.01:1 to 100:1. Most commonly the 
molar ratio of carbonyl to oxycarbonyl is from 0.1 to 10. 
The environmentally degradable poly(keto-esters) obtained in accordance 
with the present process are useful as plastics and waxes. The products 
are also useful as adhesives and coatings. They can be substituted for 
conventional materials having comparable physical properties in known 
applications. 
The following examples illustrate the invention more fully; however, they 
are not intended as a limitation on the scope thereof. In the examples, 
all parts, percentages and ratios are on a weight basis unless otherwise 
indicated. 
EXAMPLE I 
A poly(keto-ester) was prepared by oxidizing an ethylene-carbon monoxide 
(ECO) copolymer resin powder containing 1.6% carbon monoxide (Mw 125,000; 
Mn 18,000). For the oxidation 10 grams ECO and 2.0 grams 
m-chloroperoxybenzoic acid (MCPBA) were charged to a flask containing 50 
mls heptane and dissolved therein. The ratio of heptane to polyketone was 
3.4:1 and the molar ratio of the oxidizing agent to carbonyl (CO) was 
2.1:1. The reaction mixture was stirred for 2 hours at 80.degree. C. and 
then cooled to room temperature. Methanol (250 mls) was added to 
precipitate the polymer. The resulting poly(keto-ester) product was 
recovered by filtration, washed with methanol and dried at room 
temperature under vacuum. Analysis of the product by infrared spectroscopy 
showed a significant decrease in the ketone carbonyl absorption (1710 
cm.sup.-1) compared to the starting ECO copolymer and a strong absorption 
at 1735 cm.sup.-1 attributable to the presence of ester carbonyl. Based on 
the relative heights of the infrared absorption peaks, the molar ratio of 
carbonyl to oxycarbonyl was estimated to be 0.11:1. The molar ratio was 
shown by nuclear magnetic resonance spectroscopy to be 0.22:1. Gel 
permeation chromatographic data showed Mw=66,600 and Mn=18,000. 
EXAMPLE II 
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 80.degree. C. approximately 80% of the carbonyl 
groups of the polyketone were converted to oxycarbonyl groups. The 
resulting poly(keto-ester) contained carbonyl and oxycarbonyl groups which 
were present in a molar ratio of 0.25:1. 
The poly(keto-ester) had a tensile strength at yield of 1650 psi and 
elongation of 540% and was useful for the preparation of sheet, film and 
molded articles. The product was also useful as a hot melt adhesive. To 
demonstrate the adhesive ability, Kraft paper was hot-melt bonded by 
sandwiching a 1" square area of adhesive between two 1".times.4" pieces of 
the paper. A shear force of 500 grams was applied and the temperature 
raised from 50.degree. C. in 5.degree. C. increments every 15 minutes. 
Shear adhesion failure (average of 5 tests) for the poly(keto-ester) did 
not occur until 116.degree. C. 
EXAMPLES III-VIII 
To demonstrate the ability to vary the process and the degree of conversion 
of carbonyl (--CO--) to oxycarbonyl (--COO--), a series of reactions were 
conducted following the general procedure of Example I. Details for these 
reactions and for the resulting poly(keto-ester) products are set forth in 
Table I. It is apparent from the data that a variety of solvents and 
conditions can be utilized for the oxidation reaction and that a wide 
variety of polyester products can be produced. 
TABLE I 
__________________________________________________________________________ 
Molar Ratio 
Reaction Diluent 
Reaction 
Reaction 
Carbonyl 
Poly(keto-ester) 
Example 
MCPBA:CO 
(Diluent:ECO) 
Temp (.degree.C.) 
Time (hours) 
Conversion (%) 
Molar Ratio CO:COO 
__________________________________________________________________________ 
III 13.4:1 Chlorobenzene 
70 20 80 0.25:1 
(11.1:1) 
IV 6.8:1 Toluene 50 24 20 4.0:1 
(8.7:1) 
V 6.8:1 Ethyl Acetate 
70 24 15 5.7:1 
(9.0:1) 
VI 6.8:1 Decalin 50 24 20 4.0:1 
(9.0:1) 
VII 6.8:1 Dimethylphthalate 
70 24 50 1.0:1 
(11.9:1) 
VIII 6.8:1 Heptane 70 24 90 0.11:1 
(6.8:1) 
__________________________________________________________________________ 
EXAMPLE IX 
A low molecular weight polyketone was oxidized using monoperoxymaleic acid. 
The monoperoxymaleic acid was prepared by reacting (1 hour at 40.degree. 
C. 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 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 70.degree. 
C., the mixture was cooled and filtered and 500 mls methanol added to the 
filtrate to precipitate the polymer. After washing with methanol, the 
polyester was dissolved in toluene and re-precipitated using 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. The poly(keto-ester) contained CO and COO present in a 
molar ratio of 4:1. 
EXAMPLES X-XIII 
A series of low molecular weight ethylene-carbon monoxide (ECO) 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 diluent was chlorobenzene. Characteristics of the ECO 
copolymers and particulars for the reaction and the resulting 
poly(keto-ester) product are set forth in Table II. 
TABLE II 
__________________________________________________________________________ 
Rn. Rn. Poly(keto-ester) 
ECO Molar Ratio 
Diluent: 
Temp 
Time Mole % Molar Ratio 
Ex. 
Mw Mn % CO 
MCPBA:CO 
ECO (.degree.C.) 
(hrs.) 
Mw Mn CO + COO* 
CO:COO 
__________________________________________________________________________ 
X 2,510 
1,240 
13.0 
2.1:1 11.1:1 
70 24 2,000 
1,000 
-- 0.1:1 
XI 2,300 
1,260 
3.2 
4.4:1 11.1:1 
70 24 2,100 
1,200 
3.0 0.1:1 
XII 
2,190 
1,040 
5.9 
2.7:1 7.9:1 
70 16 1,900 
1,000 
-- 0.1:1 
XIII 
2,270 
1,130 
10.0 
2.5:1 13.1:1 
70 20 2,000 
1,100 
9.6 0.1:1 
__________________________________________________________________________ 
*Mole % was determined by nuclear magnetic resonance spectroscopy 
EXAMPLE XIV 
Ethylene-carbon monoxide copolymer pellets [1.6 wt. % (1.6 mole %) carbon 
monoxide; Mw 125,000; Mn 18,000] were suspended in 10 mls chlorobenzene 
with 1.6 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 
pellets (recovered by filtration) were washed with toluene 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.sup.-1. Based on the relative 
intensities of the keto and ester peaks the conversion of ketone to ester 
functionality was estimated to be 35%. The poly(keto-ester) contained 
carbonyl and oxycarbonyl present at a molar ratio of 1.9:1. 
EXAMPLE XV 
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 8.8:1) 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 poly(keto-ester) product had carbonyl and 
oxycarboxyl groups, present in essentially a 1:1 molar ratio, randomly 
distributed throughout the polymer chain. 
EXAMPLE XVI 
One gram of the polyketone of Example XV was dissolved in 25 mls 
chlorobenzene by heating at 90.degree. C. The solution was cooled to 
65.degree. C. and 3.0 grams maleic anhydride and 2.0 grams 30% aqueous 
hydrogen peroxide added thereto. The reaction mixture was maintained at 
65.degree. 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 reprecipitated 
using methanol. The infrared spectrum of the dried polymer showed the 
presence of an ester peak at 1735 cm.sup.-1. Conversion of carbonyl to 
oxycarbonyl was estimated by infrared spectroscopic analysis to be 20% 
producing a molar ratio of CO:COO in the resulting poly(keto-ester) of 
4:1. 
EXAMPLE XVII 
To further demonstrate the versatility of the invention and the ability to 
produce poly(keto-esters) by oxidizing polyketones containing functional 
groups, a commercially available ethylene-vinyl acetate-carbon monoxide 
terpolymer 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.degree. C. The 
solution was then cooled to 65.degree. C. and 3.0 grams 
m-chloroperoxybenzoic acid (55% purity) added thereto. The mixture was 
stirred at 65.degree. C. 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. The poly(keto-ester) 
contained 12.1 mole percent CO+COO present at a molar ratio of 99:1. 
EXAMPLE XVIII 
To demonstrate the degradability of the poly(keto-esters) prepared in 
accordance with the process of this invention by living organisms, the 
products of Examples X, XI, XII, and XIII were tested following the 
procedure outlined in ASTM G-21-70, "Determining Resistance of Synthetic 
Polymeric Materials to Fungi." For comparison, the polyketones used to 
obtain products X, XI, XII and XIII were also evaluated. For the test, 
approximately one gram of polymer film coated on a fiberglass tape was 
placed on a mineral salts agar medium and sprayed with a combined 
suspension of spores of Aspergillus Niger, Penicillium Funiculosum, 
Chaetomium Globosum, Gliocladium Virens and Aureobasidium Pullulans. After 
inoculation, the samples and placed in an incubator maintained at 
30.+-.1.degree. C. and relative humidity greater than 85%. After 60 days, 
the samples were removed and the weight loss recorded. Results were as 
follows: 
______________________________________ 
Percent Weight Loss 
______________________________________ 
Ex. X Poly(keto-ester) 
23 
Ex. XI Poly(keto-ester) 
4 
Ex. XII Poly(keto-ester) 
3 
Ex. XIII Poly(keto-ester) 
18 
Polyketone used for Ex. X 
&lt;1 
Polyketone used for Ex. XI 
&lt;1 
Polyketone used for Ex. XII 
&lt;1 
Polyketone used for Ex. XIII 
&lt;1 
______________________________________ 
It is apparent from the above data that polyketones which are essentially 
inert to the action of living organisms can be rendered biodegradable by 
converting a portion of the carbonyl moieties to ester groups. The above 
examples further illustrate that biodegradability is enhanced as the 
oxycarbonyl content is increased. This can be accomplished by utilizing 
polyketones having higher levels of copolymerized carbon monoxide and/or 
by converting more of the carbonyl functionality to oxycarbonyl groups.