WO1999015575A1

WO1999015575A1 - Process for the copolymerisation of carbon monoxide with an olefinically unsaturated compound and new copolymers

Info

Publication number: WO1999015575A1
Application number: PCT/EP1998/006053
Authority: WO
Inventors: Sami Karaborni; Guy Lode Magda Maria Verbist; Rudolf Jacobus Wijngaarden; Nico Maria VAN OS
Original assignee: Shell Internationale Research Maatschappij B.V.; VAN OS-SCHRIER, Johanna, Maria, Hendrika
Priority date: 1997-09-24
Filing date: 1998-09-23
Publication date: 1999-04-01
Also published as: AU9746098A; ZA988666B; GB9720332D0

Abstract

A solution copolymerisation process, for copolymerisation of carbon monoxide with an olefin to make a polyketone copolymer, comprises contacting the monomers in the presence of a Group VIII metal catalyst, in a solvent comprising a compound of general formula R1-CH(Q1H)-(X)¿n?-CH(Q?2H)-R2¿ (formula A) wherein X represents a group of formula -CHR3-, n is 0 or 1, Q?1 and Q2¿ represents sulphur or oxygen, and at least one of the moieties R?1, R2 and R3¿ comprises a group which is able to effect hydrogen bonding with molecules of formula A. A preferred solvent is glycerol. The polyketone copolymer formed is believed to react with the compound A to form a ketal derivative and to be held in solution as a result of hydrogen bonding via at least one of the moieties R?1, R2 and R3¿. Treatment of the solution with water precipitates the polyketone copolymer.

Description

PROCESS FOR THE COPOLYMERISATION OF CARBON MONOXIDE

WITH AN OLEFINICALLY UNSATURATED COMPOUND

AND NEW COPOLYMERS

The invention relates to a process for the preparation of polyketone copolymers, the process comprising the copolymerisation of carbon monoxide with an olefini- cally unsaturated compound, or compounds, in the presence of a Group VIII metal containing catalyst composition; and to certain copolymers believed to be new.

Processes of this kind for preparing the polyketone copolymers are well known in the art, for example from EP-A-213671 and EP-A-619335. The copolymers prepared are linear copolymers wherein the monomer units originating from carbon monoxide and the monomer units originating from the olefinically unsaturated compound, or compounds, occur in alternating or substantially alternating order. In EP-A-213671 it is mentioned that such a copoly- merisation is carried out in a liquid diluting agent, and that lower alcohols such as methanol and ethanol are very suitable as liquid diluting agents . In the examples methanol is the liquid diluting agent. The copolymer is not soluble in methanol, or other lower alcohols, and at the end of the process the precipitated copolymer is filtered off. Such processes are called suspension or slurry copolymerisation processes.

In EP-A-619335 it is mentioned that the catalyst compositions for the copolymerisation of carbon monoxide and an olefinically unsaturated compound can be used in either the gas-phase or the liquid-phase, the term liquid-phase also including slurry processes. Suitable solvents are said to be ketones (e.g. acetone), ethers, glycol ethers, chlorinated solvents (e.g. chloroform, dichloromethane) , hydrocarbon solvents (e.g. cyclohexane, toluene), methanol and ethanol. It should be noted that although the term solvents is used these compounds are only solvents for the reactants; they do not dissolve the copolymer which forms. In the examples the solvents are dichloromethane and acetone and in each case the copolymer was collected by filtration.

In EP-A-121965 it is mentioned that a polymerisation process of this type can be carried out employing solution polymerisation or suspension polymerisation methods. Lower alcohols, ethers, glycols and glycol ethers are said to be suitable diluents. In the examples the diluents used are methanol, diglyme, diethylene glycol, 1, -butanediol and acetonitrile . The diluents do not dissolve the copolymer and accordingly these examples are all of slurry copolymerisation processes.

There are many similar prior art disclosures and whilst they generally do not explicitly exclude the possibility of carrying out solution copolymerisation, in which the copolymer is dissolved in the diluent, and occasionally even mention it as a possibility, they only provide specific disclosures of liquid-phase processes in which the copolymer precipitates from the diluent i.e. slurry copolymerisation processes. EP-A-412671 discloses a hemiacetalised copolymer obtained by reacting a polyketone with a diol of formula HOZOH, where Z represents the group -(C(R)2)n-' ^t^ ^{e R} groups independently being H, OH, or C]_-IQ alkyl or hydroxyalkyl and n being 2 to 6. Preferably, Z is selected from -CH₂-CH -, -CH₂-CH (CH₃) - and -CH(CH₃)-.

The preparation of the polyketone used for this reaction is by a conventional slurry copolymerisation process using methanol as diluent. It is stated that the hemiacetalised copolymers are readily soluble in a range of solvents such as tetrahydrofuran and dichloromethane, whereas the starting polyketones have poor solubility in anything other than extremely expensive or high boiling solvents, such as hexafluoroisopropanol and meta-cresol. A similar disclosure can be found in EP-A-409493, also relating to copolymers derived from polyketones, themselves prepared by convention slurry copolymerisation.

In EP-A-324998 there is a further disclosure of the derivatisation of a polyketone, itself produced by a conventional slurry copolymerisation process, by reaction of at least two-thirds of the ketone groups of the polyketone with an amine or a 1, 2-dihydroxyalkane, to make various derivatives set out in that specification. Examples of the 1, 2-dihydroxyalkanes are stated to be ethylene glycol, glycerol, 1, 2, 6-hexanetriol, 1, 2, -hexanetriol, 1, 2 , 5-pentanetriol and 1,2-pentane- diol.

EP-A-360358 discloses a process for the solvent spinning of polyketone fibres and mentions as solvents hexafluoroisopropanol, m-cresol and mixtures thereof. It is stated that non-solvents may be employed, in a minor amount, in combination with the solvents. Non-solvents mentioned include aromatic hydrocarbons, lower aliphatic alcohols, aliphatic hydrocarbons, ketones and acids. The present invention relates in one aspect to a novel solution polymerisation process for preparing copolymers of carbon monoxide and an olefinically unsaturated compound, or compounds.

In accordance with a first aspect of the present invention there is provided a solution polymerisation process, comprising the step of copolymerising carbon monoxide and an olefinically unsaturated compound in the presence of a Group VIII metal containing catalyst composition and in the presence of a solvent comprising a compound of general formula - A -

R¹ -CH ( Q¹H ) - ( X ) _n-CH ( Q²H ) -R² ( formula A )

wherein X represents a group of formula -CHR^- and n represents 0 or 1, Q1 represents an oxygen or sulphur atom, Q² represents an oxygen .or sulphur atom and at least one of R^, R² and R^ represents a moiety which is able to effect hydrogen bonding with molecules of formula A under the process conditions selected, sufficient to maintain the process as a solution copolymerisation process.

Preferably at least one of R^, R² and R^ represents an alkyl group substituted by a moiety selected from a hydroxy group, a thiol group, an amino or monoalkylamino group, an amido or monoalkylamido group, a halogen atom (preferably a chlorine or fluorine atom) , or a carboxylic acid group or an acid halide or ester thereof. In accordance with a second aspect of the present invention there is provided a solution polymerisation process, comprising the step of copolymerising carbon monoxide and an olefinically unsaturated compound in the presence of a Group VIII metal containing catalyst composition and in the presence of a solvent comprising a compound of general formula

Ri-CrMQ¹!.)- (X)_n-CH(Q²H) -R² (formula A)

wherein X represents a group of formula -CHR^- and n represents 0 or 1, Q1 represents an oxygen or sulphur atom, Q² represents an oxygen or sulphur atom, at least one of R1, R² and R^ represents an alkyl group substituted by a moiety selected from a hydroxy group, a thiol group, an amino or monoalkylamino group, an amido or monoalkylamido group, a halogen atom (preferably a chlorine or fluorine atom) , or a carboxylic acid group or an acid halide or ester thereof.

The following definitions apply both to the first and second aspects of the present invention as presented above .

The skilled reader will appreciate that any of R^, R² and R- which does not represent a moiety or an alkyl group as defined hereinbefore, represents an organic group or, preferably, a hydrogen atom.

In general, any alkyl group mentioned herein may suitably be a C_]__g alkyl group, preferably a C_]__4 alkyl group, more preferably an ethyl group or, especially, a methyl group. Thus, most preferably a monoalkylamino group is methylamino; most preferably a monoalkylamido group is methylamido; and most preferably a substituted alkyl group is a substituted methyl group. It will be appreciated that smaller alkyl groups are in general preferred over larger alkyl groups because, in the absence of other factors, the polar character of the compounds of the general formula A will be more substantial, and hence stronger hydrogen bonding may be expected, and better dissolution of the copolymer. However, it should be noted that the apolar character of a larger alkyl group could be counteracted by the selection of more strongly hydrogen bonding groups or of more groups able to effect hydrogen bonding.

Suitably at least one of R! and R² represents an alkyl group substituted by a moiety selected from a hydroxy group, a thiol group, an amino or monoalkylamino group, an amido or monoalkylamido group, a halogen atom (preferably a chlorine or fluorine atom) , or a carboxylic acid group or an acid halide or ester thereof. Preferably at least one of R^ and R² represents an alkyl group substituted by a moiety selected from a hydroxy group, an amino group, an amido group or a fluorine atom. More preferably at least one of R^ and R² represents a hydroxyalkyl group.

Most preferably at least one of R! and R² represents a hydroxymethyl group.

Suitably R-3 represents an alkyl group substituted by a moiety selected from an amino or monoalkylamino group, or an amido or monoalkylamido group, a halogen atom (preferably a fluorine or chlorine atom) or a carboxylic acid group or an acid halide or ester thereof.

Preferably, however, R^ represents an unsubstituted alkyl group or, especially a hydrogen atom. Most preferably n is 0.

Both moieties represented by R-L and R² may be able to effect hydrogen bonding with a compound of formula A under the process conditions selected. In such a case both moieties R^ and R² may be selected from the lists given herein, and may be different but are preferably identical .

However in other embodiments the moiety represented by R! may be able to effect hydrogen bonding and the moiety represented by R² may not. For example R² may suitably represent an alkyl group, or an alkoxyalkyl group, or, preferably, a hydrogen atom.

As for the moiety R3, this may be able to effect hydrogen bonding irrespective of whether R^ and/or R² can do so. However, as indicated above, whilst the possibility is not excluded, it is preferred that R^ is not able to effect hydrogen bonding, in which case R^ suitably represents an alkyl group, or an alkoxy alkyl group, or, preferably, a hydrogen atom.

In preferred embodiments only the moiety represented by R! is able to effect hydrogen bonding. Most preferably R! represents hydroxymethyl and R² represents hydrogen.

Preferably Q! and Q² both represent oxygen atoms. A preferred solvent is glycerol (formula A : Q1 = Q2 = o; R¹ = -CH₂0H; R² = H; n = 0) Without being bound by any theory, it is believed that the copolymer formed in the invented polymerisation processes stays in solution because of the derivatisation of at least a proportion of the ketone groups

0

II -C-

to cyclic groups carrying groups R^, R² and, when present, R^, with loss of a water molecule, and because of the hydrogen bonding between at least one of the groups R1, R² and R3 thereof, and molecules of formula A. The cyclic groups are predominantly ketal groups of general formula

It should be noted that should this theory prove incorrect in any way the operation and utility of the present invention is unaffected. The reaction may be effected with water removal as it progresses, but this has not been found to be necessary, and so is not preferred.

The term "polyketone copolymer" is used herein to denote the copolymer which has alternating ketone groups substantially throughout its length with substantially no cyclic groups, and the term "derivatised copolymer" is used herein to denote the copolymer, having at least a proportion of its ketone groups derivatised to cyclic groups.

The invention extends to a process, as defined above, for preparing a said derivatised copolymer, the process comprising the copolymerisation of carbon monoxide with an olefinically compound in the presence of a solvent of formula A, in which process at least a proportion of the said ketone groups are derivatised as described above.

The said solvent for the reaction is suitably present in substantial excess, by weight on the weight of the copolymer formed, typically at least 10:1 by weight, but of course the lower limit of the excess is ultimately determined by the solubility of the copolymer in the solvent. The proportion of the ketone groups of the polymer which react with the compound A has not been determined under different conditions and in a sense is not critical: if a sufficient reaction and sufficient degree of hydrogen bonding occurs the process will be a solution polymerisation in accordance with the invention; if it does not, the process will be a slurry polymerisation akin to the prior art processes. Olefinically unsaturated compounds which can be used as monomers in the copolymerization process of the invention include compounds consisting exclusively of carbon and hydrogen and compounds which in addition comprise hetero atoms, such as unsaturated esters, ethers and amides. Unsaturated hydrocarbons are preferred. Examples of suitable olefinic monomers are lower olefins, such as ethene, propene and butene-1, cyclic olefins such as cyclopentene, aromatic compounds, such as styrene and α-methylstyrene and vinyl esters, such as vinyl acetate and vinyl propionate. Most preference is given to ethene and mixtures of ethene with another olefinically unsaturated compound, in particular an α-olefin, such as propene or butene-1. The term "lower" used in this document to specify an organic compound has the meaning that the organic compound contains up to 6 carbon atoms. Generally, the molar ratio of on the one hand carbon monoxide and on the other hand the olefinically unsaturated compound (s) used as monomer is selected in the range of 1:5 to 5:1. Preferably the molar ration is in the range of 1:2 to 2:1, substantially equimolar rations being preferred most.

Examples of suitable Group VIII metals for use in the catalyst composition are nickel and cobalt. However, the Group VIII metal is preferably a noble Group VIII metal, of which palladium is most preferred.

The Group VIII metal is typically employed as a cationic species. As the source of Group VIII metal cations conveniently a Group VIII metal salt is used. Suitable salts include salts of mineral acids, such as sulphuric acid, nitric acid, phosphoric acid, perchloric acid and sulphonic acids, and organic salts, such as acetylacetonates. Preferably, a salt of a carboxylic acid is used, for example a carboxylic acid with up to 8 carbon items, such as acetic acid', trifluoroacetic acid, trichloroacetic acid, propionic acid and citric acid. Palladium (II) acetate and palladium (II) tri- fluoroacetate represent particularly preferred sources of palladium cations. Another suitable source of Group VIII metal cations is a compound of the Group VIII metal in its zero-valent state. The catalyst composition of the invented process is preferably based, as an additional component, on a ligand which forms a complex with the Group VIII metal. It would appear that the presence of two complexing sites in one ligand molecule significantly contributes to the activity of the catalysts. It is thus preferred to use a ligand containing at least two dentate groups which can complex with the Group VIII metal. Although less preferred, it is also possible to employ a monodentate ligand, i.e. a compound which contains a single dentate group which can complex with the Group VIII metal, in particular a dentate group of phosphorous . Suitably a bidentate ligand is used which contains two phosphorus-, nitrogen- or sulphur- containing dentate groups. It is also possible to use a mixed bidentate ligand such as 1-diphenylphos- phino-3-ethylthiopropane .

A preferred group of bidentate ligands can be indicated by the general formula

_R4_R5_Ml__R__M2_Rβ_R7 _(I)

In this formula M¹ and M² independently represent a phosphorus, nitrogen, arsenic or antimony atom, R⁴, R^,

R and R⁷ independently represent a non-substituted or polar substituted hydrocarbyl group, in particular of up to 10 carbon atoms, and R represents a bivalent organic bridging group containing at least 1 carbon atom in the bridge.

In the ligands of formula (I) M¹ and M² preferably represent phosphorus atoms. R⁴ , R^, R^ and R⁷ may independently represent optionally polar substituted alkyl, aryl, alkaryl, aralkyl or cycloalkyl groups. Preferably at least one of R , R⁵, R⁶ and R⁷ represents - Ir an aromatic group, in particular an aromatic group which is polar substituted.

Suitable polar groups include halogen atoms, such as fluorine and chlorine, alkoxy groups such as methoxy and ethoxy groups and alkylamino groups such as methylamino, dimethylamino and diethylamino groups. Alkoxy groups and alkylamino groups contain in particular up to 6 carbon atoms, more in particular up to 4 carbon atoms in each of their alkyl groups. It is preferred that one or more of R⁴ , R^, R^ and R⁷ represents an aryl group, preferably a phenyl group, substituted at an ortho position with respect to M^ or M² with an alkoxy group, especially a methoxy group. In the ligands of formula (I), R preferably represents a bivalent organic bridging group containing from 2 to 4 bridging atoms, at least two of which are carbon atoms. Examples of such groups R are -CH₂-CH₂-,

-CH₂-CH₂-CH₂-, -CH₂-C(CH₃)₂-CH₂-, -CH₂-Si (CH₃ ) ₂-CH₂- , and -CH₂-CH₂-CH₂-CH₂- . Preferably R is a trimethylene group. Preferred ligands are 1, 3-bis [bis (2, 4-dimethoxy- phenyl) -phosphino] propane, 1, 3-bis [bis (2, 4, β-trimethoxy- phenyl) -phosphino] propane and, more preferred, 1,3—bis- [bis (2-methoxyphenyl) phosphino] propane.

Other suitable bidentate ligands are nitrogen containing compounds of the general formula

χi X²

/ \ / \

N = C - C = N

wherein X^- and X² independently represent organic bridging groups each containing 3 or 4 atoms in the bridge at least 2 of which are carbon atoms. There may be an additional bridging group connecting the bridging groups χl and X². Examples of such compounds are 2,2' -bipyridine, 4,4' -dimethyl-2, 2 ' -bipyridine, 4,4' -dimethoxy-2, 2 ' -bipyridine, 1, 10-phenanthroline, , 7-diphenyl-l, 10-phenanthroline and 4 , 7-dimethyl-l, 10- phenanthroline . Preferred compounds are 2, 2 ' -bipyridine and 1, 10-phenanthroline .

Again other suitable bidentate ligands are sulphur containing compounds of the general formula

R⁸S-Q-SR⁹

wherein R° and R⁹ independently represent a non-sub- stituted or polar substituted hydrocarbyl group and Q represents a bivalent bridging group containing 2 to 4 carbon atoms in the bridge. The groups R⁸ and R⁹ are preferably alkyl groups, each having in particular up to 10 carbon atoms. Very suitable bis thio compounds are 1 , 2-bis (ethylthio) ethane and 1, 2-bis (propylthio) ethene . The amount of bidentate ligand supplied may vary considerably, but is usually dependent on the amount of Group VIII metal present in the catalyst composition. Preferred amounts of bidentate ligands are in the range of from 0.5 to 8, more preferably in the range of from

0.5 to 2 moles per gram atom of Group VIII metal, unless the bidentate ligand is a nitrogen bidentate ligand, in which case the bidentate ligand is preferably present in an amount of from 0.5 to 200 and in particular 1 to 50 moles per gram atom of Group VIII metal. The mono- dentate ligands are preferably present in an amount of from 0.5 to 50 and in particular 1 to 25 moles per gram atom of Group VIII metal.

The Group VIII metal containing catalyst compositions may be based on another additional component which functions during the copolymerization as a source of anions which are non- or only weakly co-ordinating with the Group VIII metal under the conditions of the copoly- merization. Typical additional components are, for example, protic acids, salts of protic acids, Lewis acids, acids obtainable by combining a Lewis acid and a protic acid, and salts derivable from such combinations. Suitable are strong protic acids and their salts, which strong protic acids have in particular a pKa of less than 6, more in particular less than 4, preferably less than 2, when measured in aqueous solution at 18 °C . Examples of suitable protic acids are the above mentioned acids which may also participate in the Group VIII salts, e.g. perchloric acid and trifluoroacetic acid. Suitable salts of protic acids are, for example, cobalt and nickel salts. Other suitable protic acids are adducts of boric acid and 1,2-diols, catechols or salicylic acids. Salts of these adducts may be used as well. Suitable Lewis acids are, for example, BF₃, A1F₃, ASF5 and Sn(CF₃S0₃)₂, and also hydrocarbylboranes, such as triphenylborane, tris (perfluorophenyl) borane and tris [bis-3, 5- ( trifluoro- methyl) phenyl] borane . Protic acids with which Lewis acids may be combined are for example sulphonic acids and hydrohalogenic acids, in particular HF. A very suitable combination of a Lewis acid with a protic acid is tetra- fluoroboric acid (HBF4) . Other compounds which function during the copolymerization as a source of anions which are non- or weakly co-ordinating with the Group VIII metal are salts which contain one or more hydrocarbyl- borate anions or carborate anions, such as sodium tetrakis [bis-3, 5- (trifluoromethyl) phenyl] borate, lithium tetrakis (perfluorophenyl) borate and cobalt carborate (Co (B_]__]_CH_]_₂) 2 ) • Again other compounds which may be mentioned in this context are aluminoxanes, in particular methyl aluminoxanes and t-butyl aluminoxanes.

The amount of the additional component which functions during the copolymerization as a source of anions which are non- or only weakly co-ordinating with the Group VIII metal is preferably selected in the range of 0.1 to 50 equivalents per gram atom of Group VIII metal, in particular in the range of from 0.5 to 25 equi- valents per gram atom of Group VIII metal. However, the aluminoxanes may be used in such quantity that the molar ratio of aluminium to the Group VIII metal is in the range of from 4000:1 to 10:1, preferably from 2000:1 to 100:1. The amount of catalyst composition used in the process of the invention may vary between wide limits. Recommended quantities of catalyst composition are in the range of 10^-8 to 10^-2, calculated as gram atoms of Group VIII metal per mole of olefinically unsaturated compound to be copolymerised with carbon monoxide.

Preferred quantities are in the range of 10^-7 to 10^~3 on the same basis.

The performance of Group VIII metal catalyst compositions in the copolymerization process may be improved by introducing an organic oxidant, such as a quinone or an aromatic nitro compound. Preferred oxidants are quinones selected from the group consisting of benzo- quinone, napththoquinone and anthraquinone . The quantity of oxidant is advantageously in the range of from 1 to 50, preferably in the range of from 1 to 20 mole per gram atom of metal of Group VIII.

The copolymerization process is usually carried out at a temperature between 20 and 200 °C, preferably at a temperature in the range of from 30 to 150 °C, and usually applying a pressure between 0.2 and 20 MPa, pressures in the range of from 1 to 10 MPa being preferred.

The copolymerisation process, which produces a derivatised copolymer in which at least a proportion of ketone groups have been derivatised to cyclic groups, is suitably followed by a recovery step in which the copolymer solution, which contains the derivatised copolymer, is treated with an aqueous medium, which causes the polyketone copolymer to precipitate from solution, whereupon it may easily be separated by a physical measure, such as filtration. The medium causing precipitation is preferably water alone.

The process is an advantageous one particularly because of the possibility of physical separation of the copolymerisation, in a reactor, and the polyketone copolymer recovery, in a downstream mixer. In slurry copolymerisation the non-compact morphology of the precipitating polyketone copolymer gives rise to a high space requirement, within the reactor. It is potentially more cost effective to provide a compact reactor, and a separate mixer, where the polyketone copolymer is obtained. Surprisingly, the polyketone copolymer so obtained has a relatively high bulk density, which indicates that it is present in a relatively compact form.

Accordingly the invention further extends to a process, as described above, for preparing a said polyketone copolymer by treatment of a derivatised copolymer with an aqueous medium. The polyketone copolymers of this invention have typically a limiting viscosity number (LVN) in the range of 0.1-10 dl/g, in particular 0.2-8 dl/g, more in particular 0.5-3 dl/g, based on viscosity measurements at 35 °C of solutions of the copolymers in hexafluoroiso- propanol .

The polyketone copolymers obtained according to the invention are suitable as thermoplastics for fibres, filaments, films or sheets, or for injection moulding, compression moulding and blow moulding applications. They may be used for applications in the car industry, for the manufacture of packaging materials for food and drinks and for various uses in the domestic sphere. They are particularly suitable for use as mono- or multifilament fibres. Polyketone polymers as defined herein formed by any process e.g. slurry polymerisation may be dissolved in a solvent as defined herein. However, in a preferred method of the invention fibres are spun direct from the copolymer solution from a solution copolymerisation process as defined herein. Solvent spinning can be followed by the application to the fibres of a medium which removes the solvent and yields fibres of the polyketone copolymer. This may be achieved by passing the fibres through a water bath, or spraying them with a water spray. Such solution spinning may be carried out effectively using solutions with a copolymer content of up to 10 %wt, for example 0.5 to 5 %wt.

Suitably the solvent-free fibres are then stretched at a suitable temperature.

Essentially, the teaching of EP-A-360358 may be applied, and is incorporated herein by reference, but with the derivatised copolymer dissolved within the solution defined herein, rather than in hexafluoroisopropanol and m-cresol, as described therein, and with the preferred solvent-removal medium being an aqueous medium, preferably water alone.

In a completely analogous manner as described for fibre spinning, the dissolved polyketone polymer can be used in a film forming process which comprises forming a film, treating the film with an aqueous medium and, optionally, stretching the film in a mono- or bidirectional drawing process.

The preparation of fibres and films of the derivatised copolymer and of the polyketone copolymer, as described above, constitute further aspects of the present invention. The invention extends in further aspects to a copolymer prepared by any process of the invention, as described herein. Thus, the invention extends to a copolymer which is a polyketone copolymer prepared by a process described herein; to a copolymer which is a derivatised copolymer carrying at least a proportion of cyclic groups instead of ketone groups, as described above; and to fibres of a said polyketone copolymer, or of a said derivatised copolymer.

The derivatised copolymers are believed to be new per se and represent further aspects of the present invention .

Thus a novel derivatised copolymer may be defined in one definition as a copolymer having the repeat units

0

~ [ C Z ] ^' repeat units B )

and

ϊ repeat units C !

wherein Z is an alkylene moiety obtainable by the incorporation into the polymer chain of an olefinically unsaturated compound and wherein Z, and the moieties Cjl,

Q² , R1, R², n and X as defined elsewhere herein, and the relative proportion of the respective repeat units B and C, are such that the said copolymer is soluble in a solvent of formula R.1¹ - CH - (X)_n- CH --RR2 I I

Q¹!. Q²H

to a concentration of at least 3% of weight of derivatised copolymer to weight of the solvent, at 90 °C, the substituents of the solvent being the same as the sub- stituents in repeat units C.

Suitably the relative proportion of the repeat units B and C is in the range (by number) about 40-95% B to 5-60% C, preferably about 60-95% B to 5-40% C, most preferably about 80-90% B to 10-20% C.

A novel derivatised copolymer may be defined in another definition as a copolymer having the repeat units

0 I -[C - Z^' ^'repeat units B)

and

^'repeat units C)

wherein Z is an alkylene moiety obtainable by the incorporation into the polymer chain of an olefinically unsaturated compound and wherein Z, and the moieties Q^,

Q², R1, R², n and X as defined elsewhere herein, and the relative proportion of the respective repeat units B and C is in the range (by number) about 40-95% B to 5-60% C, preferably about 60-95% B to 5-40% C, most preferably about 80-90% B to about 10-20% C. The invention is now illustrated by means of the following example.

A linear alternating polyketone copolymer was prepared as follows . A 2 litre experimental reactor was charged with

1000 g glycerol, and the catalyst, comprising: palladium acetate; 1, 3-bis [bis (ortho-methoxyphenyl) -phosphino] - propane; and trifluoroacetic acid, the molar ratio of the components being 1; 1.1; 6 and the concentration of palladium on glycerol being 10 ppm by weight. The reactor was heated to 90 °C and pressured with 25 bar pressure of ethylene, followed by an additional 25 bar pressure of carbon monoxide. The reactor content was then stirred for two hours with a specific power input in excess of 3 W/kg. The rate of formation of the copolymer was approximately 10 kg copolymer/ (g palladium, hour) .

It was found that the copolymer formed was soluble i.e. a gel was formed. X-ray analysis was carried out on the reactor contents and the diffractogram showed that no solid crystalline phase was present. No solid particles were visible under an optical microscope.

At a copolymer concentration of approximately 5% by weight on weight of glycerol the reaction was terminated. NMR testing gave the result that 10-20% of the ketone groups had been cyclised to dioxolane groups, with the other ketone groups remaining unreacted.

It was found that the required copolymer could be easily recovered by blending the solution issued from the reactor with water in a downstream mixer. The copolymer precipitated from the solution and was removed by filtration. The LVN was 1.1 dl/g and the melting point was 270 °C. The bulk density was 500-600 kg/m³. The filtrate could be dried, yielding the glycerol containing the catalyst, to be recycled.

Claims

C L A I M S

1. A solution polymerisation process, comprising the step of copolymerising carbon monoxide and an olefinically unsaturated compound in the presence of a Group VIII metal containing catalyst composition in the presence of a solvent comprising a compound of general formula

R¹-CH(Q¹H) -(X)_n-CH(Q²H)-R² (formula A)

wherein X represents a group of formula -CHR³- and n represents 0 or 1, Q! represents an oxygen or sulphur atom, Q² represents an oxygen or sulphur atom, and at least one of R^, R² and R³ represents a moiety which is able to effect hydrogen bonding with molecules of formula A under the process conditions selected, sufficient to maintain the process as a solution polymerisation process .

2. A process as claimed in claim 1, characterised in that at least one of the moieties R^, R² and R³ represents an alkyl group substituted by a moiety selected from a hydroxy group, a thiol group, an amino or monoalkylamino group, an amido or monoalkylamido group, a halogen atom or a carboxylic acid group or an acid halide or ester thereof.

3. A solution polymerisation process, comprising the step of copolymerising carbon monoxide and an olefinically unsaturated compound in the presence of a Group VIII metal containing catalyst composition in the presence of a solvent comprising a compound of general formula Ri -CrM Q¹!. ) - ( X ) _n-CH ( Q² H ) -R² ( formula A)

wherein X represents a group of formula -CHR³- and n represents 0 or 1, Q! represents an oxygen or sulphur atom, Q² represents an oxygen or sulphur atom, and at least one of R^, R² and R³ represents an alkyl group substituted by a moiety selected from a hydroxy group, a thiol group, an amino or monoalkylamino group, an amido or monoalkylamido group, a halogen atom or a carboxylic acid group or an acid halide or ester thereof.

4. A process as claimed in claim 2 or 3, characterised in that at least one of R1 and R² represents an alkyl group substituted by a moiety selected from a hydroxy group, an amino group, an amido group or a fluorine atom.

5. A process as claimed in claim 4, characterised in that at least one of R^ and R² represents a hydroxymethyl group.

6. A process as claimed in any preceding claim, wherein

R³ represents a hydrogen atom.

7. A process as claimed in any preceding claim, wherein n is 0.

8. A process as claimed in any preceding claim, characterised in that Q_l and Q² both represent oxygen.

9. A process as claimed in any preceding claim, characterised in that the solvent is glycerol.

10. A process as claimed in any preceding claim, characterised in that the polyketone copolymer formed is separated in a recovery step in which the copolymer solution from the copolymerisation step is treated with an aqueous medium which causes the polyketone copolymer to precipitate.

11. A process for providing fibres of a polyketone polymer of carbon monoxide and an olefinically unsaturated compound, the process comprising the spinning of fibres from a solution of the copolymer in a solvent of general formula A as defined in any of claims 1 to 8, and the application to the fibres so formed of an aqueous medium.

12. A process for providing films of a polyketone polymer of carbon monoxide and an olefinically unsaturated compound, the process comprising forming a film a solution of the copolymer in a solvent of general formula A as defined in any of claims 1 to 8, and treating the film with an aqueous medium.

13. A copolymer which is obtainable by a process as claimed in any preceding claim.

14. A copolymer having the repeat units

0

II

-[C - Z]- (repeat units A)

and

units C)

Q², R¹, R², n and X, defined by any of claims 1 to 9, and the relative proportion of the respective repeat units B and C are such that the said copolymer is soluble in a solvent of formula R¹ - CH -(X)_n- CH -R² I I

Q¹ti Q²H

to a concentration of at least 3% of weight of copolymer to weight of the solvent, at 90 ┬░C .

15. A copolymer having the repeat units

0

-[C - Z] ^repeat units B)

and

units C)

wherein Z is an alkylene moiety obtainable by the incorporation into the polymer chain of an olefinically unsaturated compound and wherein Z, and the moieties Q¹,

Q², R1, R², n and X, defined by any of Claims 1 to 9, and the relative proportion of the respective repeat units B and C is in the range (by number) about 40-95% B to about 5-60% C.