IE54967B1 - Process and polymers - Google Patents

Description

The invention relates to ring-containing polymers, to processes for the production thereof and to polymeric blends comprising such polymers.

Homopolymers of 1,4-cyclohexadiene and copolymers thereof with sulphur dioxide are known. Whilst we have been unable to polymerise 1.2- dihyroxycyclohexa-3,5-diene by free radical or ionic polymerisation we have now found that polymerisable compositions which comprise certain 1.2- disubstitutedcyclohexa-3,5-dienes and certain homologues and analogues thereof, which 1.2- substituents, which may be the same or different, are not hydroxy groups and do not unduly inhibit polymerisation of the polymerisable composition, can, under suitable conditions, be homopolymerised, or copolymeri6ed with suitable polymerisable comonomers to produce polymers which have a useful combination of properties. Such polymers and processes for the preparation thereof are claimed in our Patent Specification No. , from which the-present application is divided.

Known polymers which have aromatic rings in the backbone thereof are, because of their intractable nature, often difficult to form or shape; and where 54967 * Preferably the 1,2-aubstituents In the l,2-disubstituted-cyclohexa-3,5-diene or homologue or analogue thereof of which the polymerisable composition which is used in the preparation of polymers for use in 5 the process of the first aspect of the present invention is comprised are els to each other since such compounds may be derived from cls-1,2-dlhydroxy-cyclohexa-3,5-dienes which may be readily prepared by biochemical processes as is more fully described in our 10 Patent Specification No. 5 31/a .

However, we do not exclude the possibility that the aforesaid substituents may be trans to each other· As examples of the aforesaid 1,2-substituents on the eyelohexa-3,5-diene we would mention inter alia 15 acyloxy, carbonate, alkoxy. amide, halide, thioeeter, urethane and xanthate substituents· Preferably the 1,2-disubsituted-cyclohexa-3,5-diene of which the polymerisable composition which is used in the preparation of polymers for use in the 20 process of the first aspect of the present invention is comprised has a structure which may be represented by the general formula: wherein each R1, which may be the same or different, is acyl, e.g. aroyl or alkanoyl, or R2OCO-, where R2 is aryl or an alkyl group having up to ten carbon atoms; and Y is hydrogen, halogen, or an alkyl group having up to four carbon atoms.

Preferably the polymer of which the polymeric composition which is used in the first aspect of the present invention is comprised has a structure which may be represented by the general formula: wherein the cyclohexenylene ring and the residue X, where X is present, may vary from unit to unit along polymer chain; each R3, which may be the same or different, is hydrogen or R1, where R1 has the meaning hereinbefore ascribed to it; X has the meaning hereinbefore ascribed to it; n and m are whole numbers; and the ratio of n:m lies in the range 1:0 to 1:100.

R2, in general formulae II and R2t in general formulae III, are preferably (a) aroyl groups, (b) alkanoyl groups having up to eight carbon atoms and lacking a hydrogen atom on the carbon atoms adjacent the carboxy group or (c) R20C0- in which R2 has the meaning hereinbefore ascribed to it; and more preferably are CH^OCO- groups.

In general formula II, Y is preferably hydrogen, chlorine, methyl or ethyl, and more preferably is hydrogen because in the polycyclohexadiene derived therefrom at least a portion of the cyclic rings may be readily aromatised. a that where Ar represents a p-phenylene group and m is zero n is greater than 120 and preferably the polymer has a crystallinity of at least 40%, more preferably at least 60% and where Ar represents a paraphenylene group and X is -S0~2" the polymeric composition has a number average molecular weight of more than 5,000.

By "polymerisable comonomer" we mean a compound which can be reacted under polymerisation conditions with a l,2-disubstituted-cyclohexa-3,5-diene which has 1.2- substituents as hereinbefore defined to form a copolymer therewith.

Examples of suitable polymerisable comonomers include vinyl monomers, for example, olefinic hydrocarbons, e.g. styrene and ethylene, methacrylates, vinyl halides, vinyl esters, acrylonitrile and tetrafluoroethylene; and compounds such as carbon monoxide, carbon dioxide and sulphur dioxide.

Preferably a polymerisable comonomer, where it is used in the preparation of a polymer which has 1.2- di6ubstituted-cyclohexenylene rings in the polymer backbone for use in the present invention, generates a "stable" radical, by which we mean a propagating radical that is stabilised by an electron withdrawing group, e.g. phenyl, cyano, acyl, since we have found that polymerisable compositions which comprise, in addition to the 1,2-disubstituted-cyclohexa-3,5-diene, such polymerisable comonomers give polymeric compositions of higher molecular weight than polymerisable compositions comprising polymerisable comonomers which generate active radicals. As examples of polymerisable comonomers which generate stable radicals we would mention inter alia methyl methacrylate, styrene and acrylonitrile. 3 54967 such polymers are polyphenylenes they often contain halogen impurities which are due to their mode of preparation.

In US 2,502,645 it is disclosed that polymers 5 bearing in-chain cyclohexadiene rings may be prepared by the polymerisation of the "vinyl" esters of cyclohexadiene- dicarboxylic acid and that such polymers have useful adhesion properties.

We have found that certain of the aforementioned 10 poly(l,2-disubstitutedcyclohexa-3.5-dienes) can be readily shaped or formed and then converted into polyphenylenes and that such polyphenylenes often contain no or less halogen impurities than polyphenylenes known hitherto.

A first aspect of the present invention provides a process for the preparation of a polymer having aromatic rings in the backbone thereof which process comprises treating a polymer which has 1.2- disubstituted cyclohexenylene rings in the polymer 20 backbone under conditions such that the 1.2- substituents are eliminated from at least substantially all of the said cyclohexenylene rings such that they are converted into aromatic rings.

A second aspect of the present invention provides 25 polymeric compositions comprising a polymer having a structure which may be represented by the general formula: -fA -(-X^r wherein the residues Ar and X, where X is present, may 30 vary from unit to unit in the polymer chain, Ar represents a divalent aromatic or substituted aromatic group and X, is a residue of one or more polymerisable comonomers as hereinafter defined and n, and m have the meanings hereinafter ascribed to them, with the proviso 7 754967 In polymers of general formula III, in substantially all of the cyclic rings, esch of the bonds which bind the cyclic ring into the polymer backbone is preferably attached to a carbon atom adjacent the olefinic double bond in the cyclic ring, i.e. the cyclic rings are bonded in the polymer backbone at the 3,6-positions.

In polymers of general formula I Ar is preferably a phenylene ring and more preferably the linkages by which the phenylene rings are bonded in the polymer backbone are para to each other.

In polymers of general formula I, and III, n is preferably greater than about 400; m is preferably O or the ratio of n:m, where group X is present, is in the range 50:1 to 1:50; the cyclic rings and the group X, where X is present, preferably form an alternating copolymer; and the group X, where present, is preferably the residue of a polymerisable comonomer chosen from the group consisting of CH, 1 3 -CH2CHAr~, -CH2C- 1 . , -chr2ch2- , -ch2-ch- , co2R 02CR4 -ch2-cz- , -ch2chci- # "CFjCFj* » —CO—, and S02-, CM (where t is t halogen atom or R4 and R4 is hydrogen or R?, where R^ has the meaning hereinbefore ascribed to it) and more preferably X is -CH2CHPh-,-CH2CMeC02Me, or -CHjCHCN-.

Certain of the 1,2-di6ubetituted-cyclohexadienes for use in the preparation of the polycyclohezadienes used in the process of the first aspect of the present invention may often be obtained via a biological 549 67 · $ pathway. For example, ciB-l,2-dihydroxycyclohexa-3,5-dienes may be prepared by suitable micro-organisms, e.g. a mutant strain of Pseudomonas putida, as is more fully described in Patent Specification No 5 5311X and the hydoxy groups thereof can be converted into suitable derivatives, e.g. ester and carbonate derivatives, by techniques well known in the art. For example, the ester derivatives can be prepared by reacting the aforesaid dihydroxy compounds with acyl 10 halides or acyl anhydrides. For ease of polymerisation, the ester or carbonate derivatives are preferably used in the preparation of the polycyclohexadienes. However, we do not exclude the possibility that the 1.2- disubstitutedcyclohexadienes may be obtained by 15 conventional organic synthesis or that the 1.2- substituents may be tran6 to each other. For example. United States Patent Specification No. 3,755,080 describes the microbial conversion of naphthalenes to 1,2-dihydro-1,2-trans-di-hydroxy 20 derivatives thereof using a Nocardia species of bacteria; Nakajima, et. al. describe the chemical synthesis of cis- and trans-l,2-dihydroxy-cyclohexane-3,5-diene in Chemische Berichte, 1959, Volume 92, pages 163-172 and 1956, Volume 89, pages 25 224-9 respectively; and Platt et al describe the chemical synthesis of trans-1,2-diacetoxycyclohexa-3,5-diene in Synthesis, 1977, Volume 7, pages 449-50.

Polymerisation of the aforesaid 1,2-disubstitutedcyclohexadienes may be initiated by conventional olefin polymerisation catalysts and free radical initiation is preferred. 3» 54967 Polymerisation of the aforesaid 1,2-disubstitutedcyclohexadienes way bo effected on a neat polymerisable composition; on a solution of the polymerisable composition in a suitable organic solvent, for example a hydrocarbon, e.g. toluene and bensene, a halohydrocarbon, e.g. 1,1,2-trichloro-l,2,2-trifluoroethane, a ketone, e.g. acetone and methyl ethyl ketone, or an eeter, e.g. ethyl acetate; or on a suspension, dispersion or emulsion of the polymerisable composition which may be in aqueous media, e.g. water, or in a suitable organic liquid, e.g. perfluoromethyldecalin, benzene or tetrafluoroethylene tetramer. Preferably the polymerisation is carried out on neat 1,2-disubstituted-cyclohexa-3,5-diene or a homologue or analogue thereof or in the presence of a suitable organic liquid.

The temperature at which polymerisation of the aforesaid 1,2-disubstituted-cyclohexadienes is carried out depends inter alia on the thermal stability of the 1.2- disubstituted-cyclohexa-3,5-diene and typically is carried out on neat 1,2-disubstituted-cyclohexa-3,5-diene or a homologue or analogue thereof or in the presence of a suitable organic liquid.

The temperature at which polymerisation of the aforesaid 1,2-disubstituted-cyclohexadienes is carried out depends inter alia on the thermal stability of the 1.2- disubstituted-cyclohexa-3,5-diene and typically is carried out in the range 10*C to 100*C.

The polymerisable composition used in the preparation of polycyclohexadienes for use in the first aspect of the present invention may comprise one or more of the aforesaid cyclohexadiene derivatives or a mixture of one or more of the aforesaid cyclohexadiene 10 derivatives and one or more polymerisable comonomers. Where one or more polymerisable comonomers is/are present it/they may provide up to 99 mole t of the polymeric product. For example, where the polymerisable comonomer is styrene we have prepared copolymers which have a styrene content which varies from 1 to 99 mole %.

The polycyclohexadienes for use in the process of the first aspect of the present invention typically have molecular weight of at least tens of thousands and often of hundreds of thousands. They are readily soluble in organic solvents, for example ketones, e.g, acetone: esters, e.g. ethyl acetate; hydrocarbons, e.g, toluene; halogenated hydrocarbons, e.g. chloroform; polar aprotic solvents, e.g. dimethyl formamide, and dimethyl eulphoxide; and protic solvents, e.g. trifluoroacetic acid and acetic acid. Films and fibres can be readily prepared from such solutions.

The polycyclohexadienes for use in the process of the first aspect of the present invention may be fabricated by conventional techniques to produce products, e.g. fibres and films.

The polycyclohexadienes for use in the process of the first aspect of the present invention readily form polymeric blends with suitable polymers. For example, a polymeric composition for use in the process of the first aspect of the present invention may be readily mixed with, e.g. dissolved in, a suitable monomer which is then polymerised. Alternatively, the aforesaid polymeric compositon and a suitable polymer may be dissolved in a common solvent and a polymeric blend recovered therefrom. As examples of suitable 11 1154967 polymers of which the blend may be comprised we would mention inter alia polystyrene, polyphenylene oxide, and polyethylene terephthalate.

Where, in polymers of general formula III the 5 groups R3 represent hydrogen, such polymeric compositions can be prepared by hydrolysis of, for example, the corresponding ester. Techniques for effecting such hydrolysis are well known in the art.

Although we do not exclude the possiblity that 10 the process of the first aspect of the present invention may be carried out by treating the polymeric composition comprising a polymer of general formula III in solution in a suitable solvent, e.g. squalane or sulpholane, it is often preferred that a neat polymeric 15 composition comprising a polymer of general formula III is employed.

Whilst the process of the first aspect of the present invention may be carried out by treating the polymeric composition of general formula III with a 20 suitable reagent, often subjecting the aforesaid polymeric composition to a suitable heat treatment is sufficient to effect aromatiaation. Suitable heat treatments typically comprise heating the aforesaid polymeric composition for several hours at a 25 temperature of, for example, 100*C to 300*C. It will be appreciated that the exact conditions used will depend on the particular polymeric composition which is used and on the substituent groups which are being eliminated. For example, where acetate groups are being 30 eliminated a temperature in the range 260*C to 290*C is often convenient; where benzoate groups are being eliminated a temperature about 250*C is often convenient. It is preferred that carbonate groups are eliminated since such elimination can be effected at 18 lower temperatures. Where carbonate groups are eliminated elimination is preferably effected in the presence of a suitable reagent. As examples of suitable reagents we would mention metal salts, e.g. halides of alkaline earth metals, e.g. potassium bromide, and bases of alkaline earth metals, e.g. potassium methoxide and potassium hydroxide.

It is often preferred that the process of the first aspect of the present invention is carried out on a polymeric composition which is in the form, e.g. of a film or fibre, which it is desired that the product of the process adopt. Furthermore, it is often preferred that the shaped and/or formed cyclohexenylene polymer is subjected to a tensile stress during treatment under the aforesaid conditions since euch a stress tends to increase the tensile modulus of the resulting product, e.g. a fibre.

Where the process of the first aspect of the present invention is carried out on a polymer which is in fibrous form, the fibres are conveniently prepared by dry spinning the polymer from a suitable solvent, e.g. methylene chloride. The fibres may then be subjected to a suitable heat treatment. For example, the heat treatment may be effected in vacuo; or in an inert atmosphere, e.g. nitrogen.

The resulting polymer is often at least 90S polyphenylene as indicated by microanalysis and IR spectroscopic analysis.

Accordingly, a third aspect of the present invention provides a process for the production of a fibre which is substantially polyphenylene which process comprises subjecting a fibre of a suitable cyclohexenylene polymer to a suitable heat treatment in 13 13 54967 an appropriate atmosphere, preferably whilat the fibre ia under a tenaile atreae to orientate the noleculea thereof· We do not exclude the poaaibility that the process of the first aspect of the present invention may be carried out on a polymer which has substantially a three dimensional shape, e.g. a solid cube. Where elimination is effected on a polymer of such a shape and Where the polymer comprises suitably volatile substituents, or derivatives thereof, which are elminated during the process, a foamed product may be produced. Where it is desired to produce a foamed product it is often preferred that the elimination reaction is effected by induction heating.

The polymeric compositions of the second aspect of the present invention typically have molecular weights of at least tens of thousands and often have decomposition temperatures of more than 250*C although it will be appreciated that the decomposition temperature will depend on the nature and amount of the polymerisable comonomer where present.

It will be appreciated that as the ratio of n>m in general formula I increases, the modulus of the resulting polymer increases to give a polymer of very high modulus, particularly when the polymer chains are orientated.

The polymeric compositions of the second aspect of the present invention readily form polymeric blends with suitable polymers, in which polymeric blends the polymers are often molecularly dispersed. As examples of such suitable polymers we would mention inter alia polyethylene terephthalate, polymethyl methacrylate. 14 14 5496? nylon, polyethersulphone, polycarbonate, polystyrene, and polyphenylene oxide.

The quantity of the polymeric composition of the second aspect of the present invention which is used in 5 the aforementioned polymeric blends depends inter alia on the properties required in the blend and on the particular polymeric composition which is used. The weight ratio of the polymeric composition to the suitable polymer may be between 1>2 and It 1000 and 10 preferably is between 1:4 and 1*20.

A polymeric blend comprising a polymeric composition of the second aspect of the present invention is preferably prepared by mixing, more preferably dissolving, a polycyclohexadiene homo or 15 copolymer of general formula III in a precursor or monomer for a suitable polymer and effecting polymerisation of the precursor or monomer under conditions such that at least a substantial proportion of, and preferably substantially all, the cyclohexenyl 20 rings in the polycyclohexadiene homo.or copolymer of general formula III are aromatised. For example, the polycyclohexadiene homo or copolymer may be dissolved in polyethylene terephthalate "prepolymer" and the polyethylene terephthalate "prepolymer" may be 25 polymerised, by known techniques, at temperatures in the range of for example, 240*C to 300*C, to form a polymeric blend.

Alternatively, a first polymeric blend may be prepared from a polycyclohexadiene homo or copolymer of 30 general formula III and a suitable polymer, e.g. polystyrene or polyphenylene oxide, for example by melt or solution blending, and the first polymeric blend may 15 15 54967 be treated, e.g. heated, auch that elimination of at least a substantial proportion of the 1,2-diaubstituenta in the polycyclohexadiene homo or copolymer of general formula III is effected.to give a S second polymeric blend comprising a polymeric composition of the second aspect of the present invention and a suitable polymer. Khere, in a polymeric blend comprising a polymeric coiaposition of the second aspect of the present invention, the aforesaid 10 polymeric composition is a polyphenylene the degree of aggregation of the polyphenylene polymer may be determined by neutron scatterin in the solid state.

The various aspects of the present invention will now be described by reference to the following 15 Examples which are illustrative of the invention.

Preparation of cls-1,2-dihydroxycyclohexa-3,5-dienes A mutant of Pseudomonas putlda HCXB 11680 was prepared using H-methyl-K1-nitro-H~nitrosoguanidine as mutagen in the procedure of Ornaton, Journal of 20 Biological Chemistry, 1966, Volume 241, pages 3800-3810.

This mutant was used in the procedures described by Gibson, Rersley, Yoshioka and Mabry, Biochemistry, 1970, Volume 9, pages 1626-1630 and Gibson, Cardini, 25 Maseles, and Kallio, Biochemistry, 1970, Volume 9, pages 1631-1635 with the appropriate aromatic compound. 1« Preparation of trans-1,2-diacetoxycyclohexa-3,5-dlene trans-1 f2-Di'aoetoxycyclohexa-3,5-diene was synthesised from 1,4-cyclohexadiene by the method of Platt et al (Synthesis, 1977 Volume 7, pages 449-50). Preparation of cis-1,2-diacetoxy-3-methyl-cyclohexa-3,5-diene cis-1,2-diacetoxy-3-methyl-cyclohexa-3,5-diene was prepared from cis-1,2-dihydroxy-3-methyl-cyclohexa-3,5-diene and acetyl chloride using the procedure as hereinafter described in Procedure λ of Examples 1-5. It had a boiling point of 120*C at l.333Pa (0.01 mm Hg).

Preparation of cis-1,2-diacetoxy-cyclohexa-3,5-diene cis-1,2-diacetoxy-cyclohexa-3,5-diene was prepared from cis-1,2-dihydroxy-cyclohexa-3,5-diene and acetic anhydride using the procedure as hereinafter described in Procedure B of Examples 1-5. It had a boiling point of 83-84'C at 9.332 Pa (0.07 urn Hg). Benzoyl Peroxide Benzoyl peroxide was dried at 20,‘C and 1.333 Pa (0.01 inn irercury) for 4 hours before use.

Preparation of Polyethyleneterephthalate ."Prcoolvmer" A mixture of dimethylterephthalate (48.54 g, 0.25 moles), ethyleneglycol (34.16 g, 0.53 moles) and manganese diacetate tetrahydrate (18.4 mg, 7.5 nmol) was heated, with agitation, under distillation until approximately the theoretical amount (16g, 0.25 mol) of methanol had been evolved. A solution (420 ul) of ortho-phosphoric acid (16.8 ul) in methanol (403 pi) was added by syringe to precipitate the catalyst as manganese phosphate and the residual traces of methanol were removed under reduced pressure. The mixture was allowed to cool to give a solid polyethylene terephthalate prepolymer. 17 54967 Examples 1-5 General Methods for the preparation of acyl and carbonate derivatives of clB-1.2-dlhydrcKycyclohexa-3,5-diene and homolocuea thereof. (a) Procedure A An ice-chilled solution of the appropriate acyl halide or chloroformate (8 mmol) dissolved in dry toluene (4 an3) or, when not readily soluble in toluene, in dry diethylether (4 an3), was added dropwise to .a. stirred solution of the 1,2-di-hydroxy-cyclohexa-3,5-diene (4cm3) in dry pyridine (4 cm3) at 0-5°C at such a rate that the temperature of the mixture did not rise above 6*C. After stirring at 0-5®C for 0.5 hours the cooling source was removed and the reaction mixture was stirred at 20*C for a further 1 hour. Solvent was removed under reduced pressure (30-40°c bath), the residue was dissolved in chloroform or diethyl ether, washed successively .with aqueous sodium carbonate and water, and dried (NajSO^ or HgSOj). Evaporation of the filtered solvent gave the crude acyl derivative which was purified by recrystallisation and/or distillation. Details of the purification and products are given in Table 1. (b) Procedure B Acetic anhydride (7.5 an3) was added dropwise to a stirred solution of the 1,2-dihydroxycyclohexa-3,5-diene (1.0 g) in pyridine (2.5 an3) at 0.5*C at such a rate that the temperature of the mixture did not rise above 6*C. The cooling source was removed, the reaction mixture was stirred at 20*C for a further 1 hour, and then worked-up' as described in Procedure A to give a crude diacetate derivative which was purified by distillation and/ or recrystallisation. Details of the purification and products are given in Table 1. 54967 1β 18 18 *•4867 Notes to Table 1 a : In nujol b i As KBr disc, c i In D6-dimethyl sulphoxlde d i In deuterochloroform.

L « cie-l,2-Dibenzoyloxy-cyclohexa-3,5-diene.

M i cis-1,2-Dibenroyloxy-3-methyl-cyclohexa-3,5-dien·. N t cis-1,2-Dipivaloyloxy-cyclohexa-3,5-diena.

O s cis-1,2-Di(methoxyXetooxy)-cyclohexa-3,5-dlene (hereinafter referred to for convenience as "bensene-cis-glyeol dimethylcarbonate).

P i cis-1,2-Diacetoxy-3-chloro-cyclohexa-3,5-diene.

Q i Crystallisation from chloroform/pentane.

R i Crystallisation from hexane· S i Distillation T » Crystallisation from pentane. 549 67 Example 6 This example illustrates the preparation of poly-(l,2-cis-dlacetoxycyclohexa-3,5-diene) from neat monomer.

A mixture of freshly distilled cis-1.2-diacctovy-5 cyclohexa-3,5-diene (2.4g, 12.2 mmole) and benzoyl per oxide (8.5mg, 35 nmole) in a glass tube was degassed under reduced pressure, frozen, and the glass tube was sealed. After 40 hours at 75 C the tube was opened and the contents thereof, in the form of a clear glass-like 10 polymer, were dissolved in chloroform. The chloroform solution was concentrated and the polymer was precipitated by the addition of methanol. The solid was filtered and dried at reduced pressure to give poly- (1,2-cis-diacetoxycyclohexa-3,5-diene) as a fluffy white solid 15 (1.84g,77?s). The infra-red spectrum of the polymer (as a K3r disc) had peaks at 2920 (C-H); 1740 (-COCHj); 1370 (rOAc); and 1240 and 1040 (C-O) cnT^·. The proton magnetic resonance spectrum of the polymer in deutero-chlorofom at 29°C gave signals at 62.05 (6H, broad 20 singlet, 2 x CHgCO-); 62.60 (2H, very broad, >CHCH * CHCH<); 64.60-6.1 (4H, very broad signal with peaks at 65.2 and 5.6, 2 x >CH0Ac and -C1I =· C1I-) . The C13 magnetic resonance spectrum of the polymer in deutero-chloroform at 29°C gave signals at 620.97 (CHgCO-, 25 sharp); 639.84 (broad, >CHCH = CH-); 668.96 (broad, >C0Ac); 6127.32 (broad, -CH *= CH-); 6169.97 (sharp, -COCHj). The weight average molecular weight (absolute) of the polymer determined by low angle laser light scattering in ethylene dicbloride was 103600 (t 2¾) and 30 in methyl ethyl ketone was 1.03 x 105. The glass 31 S4S67 transition temperature and the decomposition temperature of the polymer were 209°C and 260°C respectively and its radius of gyration (measured in methyl ethyl ketone) was 26 nanometres.

Examples 7-9 These examples illustrate the solution preparation of poly (l,2-cis-dlacetoxyc<'clohexa-3,5-diene).

A mixture of cis-l,2-diacetoxycyclohexa-3,5-diene (500 mg, 2.6 mmol) and benzoylperoxide (9 mg, 37 μηοΐ) 10 in solvent (2.0 cm3) in a glass tube was degassed under reduced pressure, frozen, and the tube was sealed.

The contents were stirred (magnetic follower) for a specified time at 80°C. The tubes were opened and,the contents were added to chloroform. The solution 15 was concentrated and poly (1,2-cls-dlacetoxvcvclo-hexa-3,5-diene) was precipitated by the addition of hexane. The polymer was characterised by infra-red spectroscopy and gel permeation chromatography. Details of the preparation and products are given in Table 2.

Examples 10 and 11 These examples illustrate the suspension preparation of poly (l,2-cis-diacetoxycYclohexa-3,5-diene), A mixture of cis-1,2-diacetoxycyclohexa-3,5-diene (500 mg, 2.6 mmol), benzoylperoxide . (9 mg, 37 jimol) and organic liquid (2an3) in a glass-tube was degassed under reduced pressure, frozen, and the tube'was sealed. The contents were vigorously stirred to disperse the 1,2-diacetoxy-cyclohexa-3,5-diene in the organic liquid. After 17 hour 30 at 80°C the tube was opened and the contents were dissolved in chloroform. The chloroform solution was concentrated and the polymer was precipitated by the addition of hexane. The precipitate was filtered, washed with hexane, and dried under reduced pressure, 35 to give poly (I,2-cis-diacetoxycyclohexa-3,5-diene) . 54967 TABLE 2 Solution Preparation of Poly(l,2-cis-diacetoxycyclohexa-3,5-diene) •P o 3 •a o u Ck O O CN o c W w a\ rp vo vo O CO CM CN 0 3 0) 3 H O £« Φ d Φ Φ »o i—l *H >i U xs o •P H φ x: 2 u vJeiglit average molecular weight. Dispersity = weight average molecular weight number average molecular weight Determined by gel permeation chromatography. Φ rH Q* S aj X W r**· co o\ as Q O 23 **4967 In Example 10,the organic liquid was perfluoro-1-methyldecalin and the yield of polymer was 67¾.

In Example 11, the organic liquid was tetra-fluoroethylene tetramer and the yield of polymer was * 5 41¾.

Example 12 This example illustrates the preparation of poly (1,2-cls-dlbenzoyloxycyclohexa-3,5-diene).

A mixture of cis-1,2-dibenzoyloxycyclohexa-3,5-10 diene (600 mg, 1.88 mmol) and benzoyl peroxide (3 mg, 12.4 uraol) in a glass tube was degassed under reduced pressure, frozen and the tube was sealed. After 18 hours at 37-98°C the tube was opened and the contents, in the form of a clear glass-like polymer, were dissolved in 15 chloroform. The chloroform solution was filtered, concentrated, and the polymer was precipitated by the slow addition of n-heptane (150 an3). The filtered precipitate was washed with pentane, and dried.under reduced pressure to give poly (1,2-cis-dlbenzoyl-20 oxycyclohexa-3,5-diene) (450 mg, 75¾). The infra-red spectrum of the polymer (as a film on NaCl) had peaks at 1720 (-COAr); 1600, 1580 (Ar); 1445, 1310, 1215 (broad), 1170, 1105, 1090, 1065, 1020 and 70S cm"1.

The proton magnetic resonance spectrum of the polymer 25 in D-6 dimethyl sulphoxide at 29°C gave signals at 44.80-6.40 (believed to be -CH CH- and 2 x >CH0C0Ph); and 46.40-8.40 (believed to be aromatic hydrogens).

The weight average molecular weight (absolute) of the polymer determined by low angle laser light scattering 30 in ethylene dichloride was 206,000.' Example 13 This example illustrates the preparation of poly (1,2-cls-dibenzoyloxy-3-methylcyclohexa-3,5-diene).

A mixture of cls-l,2-dlbenzoyloxy-3-methyl-35 cyclohexa-3,5-diene (1.50 g, 4.5 mmol) and benzoyl-peroxide (12 mg, 49.6 )imol)in a glass tube was 54967 2*4 degassed under reduced pressure, frozen and the tube sealed. Alter 17 hours at 90-95°C the tube was opened, the contents were dissolved in chloroform and the polymer was precipitated by the addition of methanol. The 5 precipitate was filtered and dried under reduced pressure to give poly(l^-cls-dibenzoyloxv-l-methvi-cyclohexa-3,5-diene) (66 mg,0.04%). The infra-red spectrum of the polymer (as a KBr disc) had peaks at 1730(-CO); 1600, 1580 (Ar); 1445; 1110, 1270, 1175, 10 1105, 1095, 1065, 1020, and 705 cm"^. The proton magnetic resonance spectrum of the polymer in deutero-chloroform at 40°C gave signals at 40.40-2.0 (3H, very broad resonance with peaks at 41.25 and 1.70, CHg-CJr); 42.20-3.80 (about 1.5H, very broad signal); 44.80-8.20 15 [(very broad signal with peaks at 45.90 (integrating about 4H and believed to correspond to 2 x >CH0C0Ph and -CH = CH-) and 47.20 and 7.70 (integrating for about 10H and believed to correspond to meta/para- and ortho- protons respectively of -COPb groups)].

Example 14 This example illustrates the preparation of poly (3-chloro-l ,2-cis-diacetoxyc'yclohexa-3,5-diene).

A mixture of 3-chloro-l,2-cis-diacetoxycyclo-bexa-3,5-diene (400 mg, 1.73 mmol) and t-butyl perben-25 zoate (4 mg,20.6 ymol) in a glass tube was degassed under reduced pressure and the tube was sealed. After 72 hours at 93°C the tube was opened and the contents were washed with methanol/pentane. The insoluble material was filtered off and dried to give poly 30 (3-chloro-l,2-cis-diacetoxycyclohexa-3,5-diene) (18 mg, 0.05%). The infra-red spectrum of the polymer (as a KBr disc) had peaks at 1750 (-C0CH,); 1370 (-0AC); 1235 and 1045 (C-0) cm . The proton magnetic resonance spectrum, of the polymer in deuterochloroform at 29°C gave signals at 42.10 (3H, singlet, -COCHj); 35 25 54967 62.15 (3H, singlet, -COCH3); 52.50-2.32 (1H, very broad >CHCH - C<);and 64.90-6.30 (4H, very bro&d, 2 x »CHOAc and -CH - CH-).

Example 15 5 This example illustrates the preparation of poly (1,2-cls-dihydroxycyclohexa-3,5-diene).

A solution (200cm3) of sodium methoxide (prepare by dissolving 5 grams of sodium in 200 am3 dry methanol) was added over 15 minutes to a solution of poly 10 (1!2-cls-diacetoxycyclohexa-3,5-diene) (300 mg), pre pared in Example 6, in hot methanol (250cm3). After the addition of about 50 cm3 the solution became cloudy and a fluffy white precipitate was deposited. The mixture was gently refluxed for 20 hours then cooled 15 and water (5 cm3) was added. The precipitate was removed by filtration, washed successively with methanol and ice cold water and dried under reduced pressure to give poly (1,2-cls-dlhydroxycyclohexa-3,5-dlqne) (145 mg, 85%). The infra-red spectrum of the product (KBr disc) 20 had peaks at 2910 (C-H); 1400 and 1055 (C—0) cm-*. The proton magnetic resonance spectrum of the product in· D-6 dimethyl sulphoxide at 70°C gave signals at 63.40-4.60 (with maxima at 63.65, 3.80 and 4.1) and 65.20-6.0 (peaking at 5.50 with a shoulder at 5.65); integral 25 intensities of the two broad signals were in the ratio of 2:1. The polymer product was found to be insoluble in acetone, chloroform, pyridine, nitrobenzene and dimethylformamide, slightly soluble in hot water, moderately soluble in dime.thyl sulphoxide and 'readily ·· 30 soluble in trifluoroacetic acid.

Examples 16 - 28 These examples illustrate the preparation of a range of copolymers of cis-l,2-dlacetoxycyclohexa-3,5-diene and styrene. a mixture of cls-1,2-diacetoxycyclohexa-3,5- dlene, benzoyl peroxide, and freshly distilled styrene 36 36 S 4 9 6 7 In a glass tube was degassed, frozen, and the tuoe was sealed. After 40 hours at 80°C, the tube was opened and the polymeric product was recovered as in 5 Example 6 to give copolymer of cis-1,2-diacetoxy- cyclohexa-3,5-diene and styrene. The infra-red spectrum of the polymers (as KBr discs) had peaks at 3030, 2930 (C-H); 1740 ICH3C0-); 1600, 1495,.1455 (polystyrene); 1370 (-OAc/PS); 1245, 1225 (shoulder) (C-0); 10 1040, 1030 (C-0); 760 and 700 (Ar) cm The proton magnetic resonance specturm of the copolymers in deuterochloroform at 29°C gave signals at 41.0-2.So (broad signal with mixirna at «1,90, 2.05 and 2.30, ArCH-CH,- in polystyrene and 2 x CH3C0- and >CHCH = 15 CHCHCH0Ac, -CH = CH-) ; 46.20- 7.40 (maxima at 56.65 corresponding to two ortho-protons, and 7.10 corresponding to one para- and two meta- protons); integral intensities gave the ratio of cyclohexenylene rings to styrene residues in the 20 copolymer. The results are given in Table 3.

TABLE 3 Example Hole % cis-1,2-diacetoxy-3,5-cyclohexadiene in copolymer product Glass Transition Temperature 16 2.5 110 17 11 127 18 22 135 19 39 136 20 53 157 21 70 167 22 31 175 23 89 1B2 24 91 190 25 92.5 202 26 93.5 202 .27 95 202 23 97.5 . 208 .--- 54967 Example 2¾ This example illustrates the preparation of a copolymer of 3-chloro-cis-l,2-diacetoxycyclohexa-3,5-diene and styrene.

A mixture of 3-chloro-cis-l,2-diacetoxycyclo-5 hexa-3,5-diene (500 mg, 2.16 mmol), azobisisobutyro-nitrile (4 mg, 24.4 ymol) and freshly distilled styrene (180 mg, 1.73 mmol) in a glass tube was degassed, frozen, and the tube was sealed. After 36 hours at 60°C the tube was opened acd the contents were poured 10 into methanol. The resulting precipitate was filtered, washed with methanol and dried under reduced pressure to give a copolymer (100 mgs) of 3-chloro-l,2-cls-diacetoxycyclohexa-3,5-diene and styrene. The infrared spectrum of the polymer (as a KBr disc) had peaks 15 at 3030, 2930 (C-H); 1750 (-COCH3); 1600, 1495, 1455 (polystyrene); 1370 (-OAc/PS); 1240, 1045 (C-0); and 700 (Ar) cm-*. The proton magnetic resonance spectrum of the copolymer in deuterochlorofarra at-40°C gave signals at <1.20-2.60 (broad signal with maxima at 20 <1.52 and 2.10 (Ar-tnCHj- in polystyrene and 2 x CH^CO- and >CHCH = CH-); <4.4-5.8 (very broad signal, -CJI * CH-and 2 x >CHOAc); <6.3-7.4 (maxima at <6.7 corresponding to two ortho protons, and <7.1 corresponding to one para-and two meta- protons in polystyrene). Integral 25 intensities indicated that the molar ratio of. cyclohexen-vlene rinos to stvrene residues in the copolvmer was Is4. Example 30 This example illustrates the preparation of a copolymer of cis-1,2-diacetoxy-3-methylcyclohexa-3,5-diene and 30 styrene.

A mixture of cis-1,2-diacetoxy-3-methylcyclc-hexa-3,5-diene (500 mg, 2.38 mmol), benzoyl peroxide (1.5 mg, 6.2 pmol), and freshly distilled styrene (400 mg, 3.85 mmol) in a glass tube was degassed, frozen, and the tube was sealed. Alter 40 hours at 90°C the contents 01 the tube were isolated as in Example & to give a copolymer (110 mgs) of cis-1.2-diacetoxy-3-methvit-yrin-hexa-3,5-diene and styrene. The infra-red spectrum of the copolymer (as a KBr disc) had peaks at 3030. 2930 (C-H); 1740 (-COCHg); 1600,.1495, 1455 (polystyrene); 1370 (-OAc/PS); 1245, 1225 (shoulder) (C-0); 760 and 700 (Ar) cm-1. The proton magnetic resonance spectrum of the copolymer in deuterochloroform at 29°c and at 50°C gave signals at 61.0-2.40 (broad signal with maxima at 61.55 and 1.90, ArCHCH2- in polystyrene and 2 x CHgCO-, CH^-C^, .and -CH = CH-CK< in diacetate 64.30-5.50 (very broad signal, -CH=CH- and 2 x >CH0Ac); 66.20-7.4 (maxima at 66.6, corresponding to two ortho- protons, and 67.05 corresponding to two meta- and one para- protons in polystyrene). Integral intensities indicated that the molar ratio of cyclo-hexenylene rings to styrene residues in the copolymer was about 1:5. The glass transition temperature of the co- · polymer (determined by DSC) was 113°C.

Example 31 This example illustrates the preparation of a copolymer of cis-1,2-diacetoxy-3-methylcyclohexa-3,5-diene and methyl methacrylate.

A mixture of cis-1,2-diacetoxy-3-m&thylcyclo-hexa-3,5-diene (480 mg, 2.29 mmol), benzoylperoxide (1.5 mg, 6.2 umol) and freshly distilled methyl methacrylate (470 mg, 4.7 mmol) in a glass tube was degassed, frozen, and the tube was sealed. After 40 hours at 90°C the tube was opened and the contents thereof were recovered as in Example 6 to give a copolymer (240 mgs) of cls-1,2-diacetoxy-3-methylcyclohexa-3,5-ciene and methyl methacrylate. The infra-red spectrum of the co- 29 54967 polymer (as ft KBr disc) had peaks at 3000, 2955 (C-H); 1740-1725 (-COCB3 and -C02CH3), 1485, 1450, 1435, 1270. (shoulder), 1245, 1195 and 1150 cm-1. The proton magnetic resonance spectrum of the copolymer' in deuter-chloroiorm at 29°C gave signals at SO.50-1.40 (maxima at 0.90 and 1.05, -CH2C(OT3)C02Me); il.40-2.30 (maxima at 1.85 and 2.10, -CH^MeCOgMe 0i PUMA and CHgC^, . >CH-CH «* CH- and 2 x CHgCO- oi acetate); 3.65 (-COjMe); 4.8-5.7 (-CH - CH- and 2 x CHOAc). Integral intensities indicated that the molar ratio of cyclq-hexenylene rings to methacrylate residues in the copolymer was about 1:13. The glass transition temperature of the copolymer was 1.14°C.

Example 32 This example illustrates the preparation of a polymer of benzene-cis-glycoldimethylcarboaate by dispersion polymerisation.

Benzene-els-g lycoldlme thy lcarbor.ate (12 a, 52.63 mmol) was placed in a 250 cm3 flask equipped with a paddle strirrer and degassed. The flask was filled with nitrogen a20bisisobutvronitrile (fi Various molecular weight data was obtained. The I.V. in dichloroethane was 0.33 and low angle laser light scattering in the same solvent gave an Mw value SO of 453811. G.P.C. molecular weights were measured as (in 32074, Mw - 2320840.

Example 31¾ This example Illustrates the polymerisation of benzene-cls glycoldimethylcarbonate by the action of U.V.* radiation.

Benzene-cis-glycoldimethylcarbonate (1 gram; 4.4 nmol) was degassed and sealed in a quartz glass tube. The tube was then held at a distance from a Phillips MLV 300V! Ultra Violet Lamp so that its temperature was held at 40°. After 92 hours the tube was opened, the solid product was dissolved in methylene chloride and precipitated in hexane. The isolated and vacuum dried polymer (0.5 g, 50% yield) had an I.V. in 1,2-dichloroethane of 0.43, and G.P.C. molecular weights Mn = 89898, Mw = 321849.

Example 34 This example illustrates the polymerisation of cls-1,2-dipivaloxycyclohexa-3,5-diene by a radical initiator in the bulk phase. cis-l,2-Dipivaloxycyclohexa-3,5-diene (1 g, 3.57 mmol) was degassed in a glass tube containing benzoyl peroxide (6.3 mg, 0.026 mmol) and sealed under vacuum. After 24 hours at 80° the tube was opened and the solid contents dissolved in methylene chloride. The polymer was precipitated in methanol, isolated and vacuum dried. The polymer (0.8 g, 80% yield) had G.P.C. molecular weights Mn = 29940, Mw = 77373. The Tg of the polymer was 240°C.

Example 35 This example illustrates the thermal polymerisation of cls-1r2-diacetoxvcvclohexa-3,5-diene in the bulk phase. 31 31 54967 c1s-1,2-placetoxycyclohexa- 3,5 -di ene (1 gram; S.l mmol) was degassed and sealed under vacuum in a glass tube. After 72 hours at 90°C, the tube was opened, the product was dissolved in methylene chloride and 5 precipitated in hexane. The isolated and vacuum dried polymer (0.114 g, 11.4% yield) had G.P.C. molecular weight values of Mn » 54930, Mw = 145510. Low angle laser light scattering in 1,2-dichloroethane gave an Mw value of 112500.

Example 36 This example illustrates the copolymerisation of cls- 1.2- diacetoxycyclohexa-3,5-diene with vinyl chloride. cis-1,2-Diacetoxycyclohexa-3,5-diene (2.53 grams; 12.9 mmol) was degassed in a glass tube containing 15 benzoyl peroxide (6 mg, 0.025 mmol). Vinyl chloride ( 10 mis, 108 mmol) was then distilled into the tube which was sealed off under vacuum. After 42 hours at 90°C the tube was opened and the contents were poured into hexane. The isolated and vacuum dried 20 copolymer (0.151 grams; 1.58% yield) was shown by microanalysis to contain 45 mol% vinyl chloride residues. The copolymer had a Tg of 144°C. The G.P.C. molecular weights of the copolymer were Mn = 2945, Mw = 8369.

Example 37 This example illustrates the copolymerisation of cis- 1.2- diacetoxycyclohexa-3,5-diene with chlorotrifluoro-ethylene. cis-1,2-oiacetoxycyclohexa-3,5-diene (1 gram? 30 5.1 mmol) was degassed in a glass tube containing benzoyl peroxide ( 4 mgs, 0.017 mmol) and chlorotri-flucroethylene (1 ml, 8.6 mmol) was distilled in and sealed off under vacuum. After 20 hours at 90°C the tube was opened, the solid contents dissolved in methylene 33 S 4 9 6.7- .. 10 15 20 25 chloride and precipitated in hexane. The isolated and vacuum dried copolymer (0.15 grams, 15% yield) was estimated by microanalysis to have 10 mole % chlorotri-fluoroethylene residues incorporated in its structure. The Tg of the copolymer was 182°C. The G.P.C. molecular weights of the copolymer were Mn ** 22969, Mw » 56443. Example 38 This example illustrates the copolymerisation of benzene-cls-glycoldimethylcarbonate with 1,3-butadiene-d6. Benzene-cls-glycoldlmethylcarbonate (2 a,. 8.8 mmol) was degassed in a tube containing azo-bis-isobutyponltrile (10 mg, 0.061 mmol) and 1,3-butadiene-d6 (1.7 an3, 19.8 mmol) was distilled in and sealed off under vacuum. After 60 hours at 50° the tube wa3 opened, the solid· contents dissolved in methylene chloride and precipitated in hexane. The isolated and vacuum dried polymer (1.3 grams, 40.8% yield) had a Tg of -15°C. The G.P.C. molecular weight values were Mn = 50155 and Mw = 148997. The proton magnetic resonance spectrum of the polymer in deutero-· chloroform at 29°C gave signals at 62.6 (2H, doublet, >CH-CH=CH-)- 63.8 (6H, sharp singlet, CH30-),'64.93 (2H, doublet, >CH0) and 65.6 (2H, singlet, -CH°CH-) Example 39 This example illustrates the preparation of poly-trans-l,2-diacetoxycyclohexa-3,5-diene) from neat monomer. A mixture of freshly distilled trans-1,2-diacetoxy-cyclohexa-3,5-diene and benzoyl peroxide in a monomer/ catalyst ratio of 102/1 in a glass tube was degassed under reduced pressure, frozen, and the glass tube was sealed. After 43 hours at 90°C the tube was opened and the contents thereof, in the form of a clear glass-like polymer, were dissolved in chloroform. The chloroform solution was concentrated and the polymer was precipitated into hexane. The solid was filtered and dried at reduced 30 33 33 54967 pressure to give poly(1,2-trans-diacetoxycyclohexa-3,5-diene) as a fluffy white solid (494 conversion)» Mw - 10240 and Mn - 5770.

Examples 40-42 5 Preparation of Polymeric Blends comprising Poly(1,2-disubstitutedcyclohexa-3,5-dienes) Procedure A The matrix polymer and the poly(1,2-disubstituted-cyclohexa-3,5-diend were each dissolved in a common 10 solvent and the two solutions were blended together. The solvent is removed under reduced pressure to give the crude blend of polymers.

Procedure B The matrix polymer and the 1,2-disubstituted-15 cyclohexa-3,5-diene are each dissolved in a common solvent and the two solutions are blended together.

A solid blend of the two polymers is then produced by their precipitation in a common non-solvent. The solid is filtered, washed and dried under reduced 20 pressure.

The results are shown in Table 4.

The presence of poly(benzene-cis-glycoldimethy1-carbonate) in the blends of Examples 40 and 41 was readily detected by infra-red spectroscopy. 34 34 S 49 6 7 Polymeric Blends comprising Ben2ene-cis-glycol-d imethylcarbonate TABLE 4 Example Matrix Polymer (Weight in grams) Weight of Ben2ene-cis-glycol-dimethyl-carbonate (qrams) Common Solvent Procedure 40 Polystyrene (0.5) 0.2 chci3 A 41 Poly-2,6-di- methyl- phenylene oxide (0.5) 0.2 CBCI3 A 42 Polyethylene- terephthalate (10.0) 1.0 cp3co2h B Examnle 43 This example illustrates the preparation of poly-para-phenylene.

A colourless film of poly-3,6(1,2-cis-diacetoxycyclohexa-3,5-diene) was dissolved onto a microscope slide from a solution of the polymer (50 rag) in dichloromethane (1cm3). The temperature of the film was raised, in a substantially oxygen-free atmosphere, over 2 hours to 320*C and was held at this temperature for 3 hours to give a pale 15 yellow film.

The infra-red spectrum of the pale yellow film (as KBr disc) had no peaks which corresponded to CH3-CO-, it had peaks at 1480, 1000 and 810 cm-1, and it was very similar to a published spectrum of 20 poly(paraphenylene) (M.B.Jones, P.Kovacic and D.Lanska, Journal of Polymer Science, Polymer Chemistry, 1981,Volume 19, pages 89-107). 549 67 Examples 44-fl9 These examples Illustrate the preparation of aromatic polymers according to the present invention.

General Method A Evaporation of an approximately 20% w/w solution of poly-(cls-1,2-dlsubstltuted-cyc.lohexa-3,5-dlene) in chloroform, which solution optionally contained an antioxidant, Irganex1i010 (about 1» w/w of polymer), and/or an elimination catalyst, e.g. potassium bromide (about 1 mole »), under 10 reduced pressure afforded a film of the polymer.

The film was heated to a specified temperature for a specified length of time. The rate of aromatisation was determined in independant experiments by isothermal gravimetric analysis (TGA) and by infra-red analysis.

The product was analysed by infra-red spectroscopy, TGA, solid state proton magnetic resonance spectroscopy and X-ray crystallography and the analyses were found to be substantially consistent with the reported data for poly-p-phenylene. (J.G,Speight, P.Kovacic and F.W.Koch, 20 Journal of Macromolecular Science, Reviews of Macromolecular Chemistry, 1971, Volume C5, pages 295-386).

Method B (Example 49) Poly (cis-l,2-disubstituted-cyclohexa-3,5-diene) powder, 25 optionally containing an antioxidant or elimination was treated to a specified thermal cycle. Analysis of catalyst the product as described in Method A confirmed that it was substantially noly-p-phenylene.

The results are given in Table 5.

Example so This example illustrates the·use of a base to catalyse elimination of 1,2-substituents from poly(cls-1,2-dlsubstltuted-cyclohexa-3,5-dlene) in the third aspect of the present invention.

Trade Mark. 3554967 ΙΛ ca ct O U ΙΛ *» 3 e o in O o .CO (O m r· <71 a\ co ΟΌ L * *·- W CT. a; a.'-' o O o O' 01 t. 3 4J Λ}«^» J.U o o o o 0)0 o o o 00 CO n CO CM Er ‘ 0) H* ; •i- Q) x o/r- +; O -U 1 s S- /lrt f— c*. α ε e m -o^ •r- «Λ X σ» ο ε co C0‘ o o o o o o o o o o o h* CO CO CO CO CO CVJ o o r" «a ·# t. e~ ft γν, O o © o CM 0) 4J s c. r- m in CO o i- ε · 3 (0 o O X z V> UJ « 0 (0 A 37 5496? A solution of sodium methoxide, prepared by dissolving sodium (4.6 grams) in methanol (50 cm3), was added dropwise over 5 minutes to a refluxing solution of poly-benzene-cls-glycoldlmethylcarbonate (2.28 grams) 5 in tetrahvdrofuran (200cm3). The mixture was cooled, filtered, and the filtered product was washed sequentially with water, methanol and pentane. Analysis of the dried product (0.7 grams) by infra-red spectroscopy, showed the product to be substantially poly-p-phenylene.

Example 51 This example illustrates production of an aromatic polymer according to the present invention.

A solution of poly-benzene-cls-glycoldlplvalate (5 grams) in squalane (100 cm3 was refluxed under nitrogen 15 for 6.5 hours. An increasing quantity of a pale yellow precipitate was produced over the duration of the experiment. The mixture was cooled, filtered and washed with pentane. Analysis of the product was consistent with the formation of poly-phenyl.ene. The infra-red 20 spectrum, showed about 90« aromatisation while X-ray analysis (ratio of crystalline reflections to amorphous halos) suggested about 40% crystallinity.

Examples 52-54 These examples illustrate production of aromatic polymers 25 according to the present invention in fibre form.

A solution of poly(cis-l,2-disubstituted-cyclo-hexa-3,5-diene) in a suitable solvent, optionally containing an anti-oxidant, e.g. Irganox 1010 (0.11 by weight of polymer) was dry. spun and the solvent 30 flashed off to give a fibre the diameter of which may be varied by altering relevant conditions, e.g. wind-up rate. 33 54967 \Ω Ui CQ o m o co Π p· ro Oon L. Ο */> c i- e 4-> J3 O o> *** i. ELU to *r- o "•s. I c (AN (0 υ >>«; -.c^ +j l- O <Λ -f- 4-> CX3 C in ·*- C o o *7 Or-*»- 1» CO t- U*r* O *J 1Λ u C*r « tor fl -*>T3 L U *—* o»·^ *o iA "Σ. o o o r^. n o r— CO CVJ o nT1 CJ o COXo omo Q) a 0) C 4-> c V to 01 c ·«" *o 0 *σ 1 t in .O m i_ • cs «0 0¾ 1 u 1 to 1—— 0 X X 0 0) Λ .C £ 0 +> 0 P— W u E u 5s V— 2S u Ό υ 5S ί- >> X Ο X 0 u o >» 4-> n— ω > D> u I <0 Cl vs I •t-| *0 *o V1 «I in I 0 ·*- c u| U | 0 1 N CO CO C * — QJ c— -O * 5s is >·, 0 0 O CL c. Cl <. a 0 39 39 5496? The aforementioned fibre is held under tension in an oxygen-free atmosphere and the temperature thereof is raised to a specified value for a specified time.

The results are given in Table 6.

Example 5S-S6 These examples illustrate the aromatisation of a range of cis-1,2-diacetoxycyclohexa-3,5-diene/styrene copolymers.

A series of cis-l,2-diacetoxycyclohexa-3,5- ciene/styrene copolymers (2.5 - 97.5 mole « styrene) were aromatised as described in Method A of Examples 44-49. Aromatised products which contained up to 70 stole % aromatic residues were completely soluble in 15 methylene chloride.

The glass softening points of the polymers containing from 25 to 93 mole I phenylene residues are shown in Table 7.

TABLE 7 Example Source of Starting Material (Example No) Mole t p-phenvlene In copolymer Softening Point l°C) 55 18 25 95 56 19 39 99 57 20 53 107 58 21 70 130 59 22 81 154 60 23 89 179 61 24 90 254 62 25 93 233 Example 63 This example illustrates the aromatisation of poly-(1,2-trans-diacetoxycyclohexa-3,5-diene).

A thin film of poly(i,2-trans-diacetoxy-cyclohexa-3,5-diene), prepared in Example 39, was solution cast (from chloroform) on to a potassium bromide disc. The disc was then placed in a nitrogen purged oven contained within an infra-red spectrophotometer such that the optical path passed through the windown and film. The disc was then heated to 285*C. Regular monitoring of the spectrum demonstrated the loss of acetate groups and the appearance of pholyphenylene.

Examples 64-66 These examples illustrate the preparation of polymeric blends comprising aromatic polymers according to present invention. 41t.

S4S67 Polymeric blends prepared in Examples 40-42 were heated at elevated temperature in an oxygen-free atmosphere.

The presence of poly-phenylene in the 5 resulting blend was shown by infra-red spectroscopy and/or by dissolution of the matrix polymer in an appropriate solvent to leave an insoluble residue of polyphenylene.

The results are given in Table 8.

TABLE 8 Example Starting blend Weight of Weight of Residual Aromatisation Conditions Dissolution (Obtained in Example) Blend (gram) Polyphenylene (grams) Temp- ertature •C Time (hrs) Solvent 64 40 0.5 0.06 260 5.5 CHClj 65 41 0.5 0.06 260 5.5 CHC13 66 42 10.0 a 285 4.5 Sodium glycolate a Not determined

Claims (16)

1. 42

2. 1. A process for the preparation of a polymer which has aromatic rings in the backbone thereof which process comprises treating a polymer which has 1.2- disubstituted-cyclohexenylene rings in the polymer backbone under conditions such that the 1.2- substituents are eliminated from at least substantially all the cyclohexenylene rings such that they are converted into aromatic rings.

3. 2. A process as claimed in claim 1 wherein the polymer which has 1,2-disubstituted-cyclohexenylene rings in the polymer backbone has a structure which may be represented by the general formula: where X is present, may vary from unit to unit along the polymer chain; R5, each of which may be the same or different, is hydrogen, acyl or RJOCO where RJ is aryl or an alkyl group having up to ten carbon atoms; X, where present, is the residue of a polymerisable comonomer which can be reacted under polymerisation conditions with a 1,2-disubstitutedcyclohexa-3,5-diene in which the 1,2-substituents are not hydroxy groups and do not unduly inhibit polymerisation of the 1,2-disubstitutedcyclohexa-3,5-diene; n and m are whole numbers and the ratio of n:m lies in the range 1:0 to 1:100. 43 54967

4. 3. A process as claimed in claim 2 wherein the polymer is subjected to a heat treatment.

5. 4. A process as claimed in claim 2 or 3 wherein the acyl group is an aroyl group or an alkanoyl roup having up to eight carbon atoms and lacking a hydrogen atom on the carbon atom adjacent the carboxy group, or S' is an aryl group or an alkyl group having up to ten carbon atoms.

6. 5. A process as claimed in claim 4 wherein RJ is methyl.

7. 6. A process for the preparation of a polymer which has aromatic rings in the backbone thereof as claimed in any of the preceding claims , wherein the polymer which has 1,2-disubstituted-cyclohexenylene rings in the backbone thereof is prepared by a process which comprises the step of treating a polymerisable composition which comprises a 1,2-disubstituted-cyclohexa-3,5-diene or homologue or analogue thereof with an olefin polymerisation catalyst under polymerisation conditions for the polymerisable· composition. 7. a polymeric composition comprising a polymer which has a structure which may be represented by the general formula: wherein Ar and X. where X is present, may vary from unit to unit along the polymer chain; Ar is a divalent aromatic or substituted aromatic group; and X, n and m have the meanings ascribed to them in claim 2 with the proviso that where Ar 44 8.43 67 represents a p-phenylene group and m ie zero, n is greater than 120; and where Ar represents p-phenylene and X is -SO,-, the polymeric composition has a number average molecular weight of more than 5000.

8. A polymeric composition at claimed in claim 7 wherein m is 2ero.

9. A polymeric composition as claimed in claim 7 or 8 wherein -Ar- is p-phenylene. 10

10. A polymeric composition as claimed in any one of claims 7 to 9 in the form of a fibre or film.

11. A polymeric blend of an organic polymer and an aromatic polymer as defined in any one of claims 7 to 9. 15

12. A process according to Claim 1 for the preparation of a polymer which has aromatic rings in the backbone thereof, substantially as hereinbefore described and exemplified.

13. A polymer which has aromatic rings in the backbone thereof, whenever prepared by a process claimed in a preceding claim.

14. A polymeric composition according to Claim 7, substantially as hereinbefore described and exemplified.

15. A polymeric blend according to Claim 11, substantially as hereinbefore described and exemplified. 26th Dated this the / day of September, 1938. E. R. KELLY a CO. BY: EXECUTIVE.

16. 27 Clyde Road, Bansonage, Dublin 4. AGENTS FOR THE APPLICANTS.