DE2849424A1 - STYRENE POLYMERISATE WITH IMPROVED THERMAL PROPERTIES - Google Patents

Description

PATENT LAWYERS

WUESTHOFF - ν. PECHMANN - BEHRENS - GOETZ

professional representatives before the european patent office agrees pres l'office europeen des brevets

DR.-ING. FRANZ WUESTHOFF LR. PHIL. FREDA WUESTHOFF (1927-1956) DIPL.-ING. GERHARD PULS (1952-I971) DIPL.-CHEM. DR. E. BARBER OF PECHMANN DR.-ING. DIETER BEHRENS DIPL.-ING .; DIPL.-WTRTSCH.-ING. RUPERT GOETZ

D-8000 MUNICH SCHWEIGERSTRASSE

phone: (089) 66 20 ji telegram: protectpatent telex: 524070

IA-5I

Patent application

Applicant: RHOEE-POUEENC INDUSTRIES 22, avenue Montaigne 75 - Paris 8§me / France

Title:

Styrene polymers with improved thermal properties

909821/0581

"3R.-ING. FRANZ

PATENT LAWYERS

wuesthof2 8 4 9 4 2 A

DR. J ¹ HIL. rKEDA WUESTHOFF (1927-I956)

WUESTHOFF - v. PECHMANN - BEHRENS - GOET2 _DIPl .. _ING . _{GERHARD rüLS} a

DIPL.-CHEM. DR. E. BARBER OF PECHMANN PROFESSIONAL REPRESENTATIVES BEFORE THE EUROPEAN PATENT OFFICE DR.-ING. DIETER BEHRENS

MANUATAIRES AGREES PRES l'OPFICE EUROPEEN DES BREVETS DIPL.-ING .; DI PL.-TJCIRTSCH.-ING. RUPERT GOETZ

D-8000 MUNICH 90 SCHWEIGERSTRASSE 2

TELEPHONE: (089) 6620 51 telegram: protectpatent Telex: 524070

IA-5I 495

Atm .: EHONE-POULENC IND.

description

The invention relates to copolymers of styrene or styrene derivatives and unsaturated compounds with imide groups and a process for the production of such copolymers.

In the PR-PS 2 O46 497 monomers are already with Described imide groups which can be polymerized to form heat-resistant polymers. In the publication stated that these compounds with imide groups copolymerize with various monomers, including styrene can, always with the aim of obtaining heat-resistant or heat-resistant plastics.

The invention is based on the object of providing polymers of the polystyrene type, which under The same conditions as polystyrene can be processed, but with certain improved polystyrene Have properties that are described in more detail below will.

The polymers according to the invention are characterized in that they are copolymers of styrene and at least a compound with imide groups of the general formula I.

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co

N 4- R

are, in which η is an integer from 1 "to 5, B. a organic group of valence η isi and can contain 2 to 50 carbon atoms and D stands for one of the following groups:

YC -

Il

YC -

^(C Vm

where Y is H, CH, or Cl and m is 0, 1 or 2; the copolymers contain from 0.1 to 20 wt -. ° / o copolymerized compound having imide group, wherein the units derived from said compound are uniformly distributed in the interior of chains formed of styrene or styrene derivative.

The molecular weight of those provided according to the invention

■ 2 r

Copolymers is generally in the range from 10 to 10.

For the sake of simplicity, the terms styrene and polystyrene are used below, the latter term also being used refers to the polymers starting from styrene and the compound with imide grouping and starting from the monomers usually combined with styrene, such as acrylonitrile, butadiene, maleic anhydride, divinylbenzene and Methyl methacrylate have been obtained. Will such If additional monomers are used, their proportion can be 50 wt .- ^, based on styrene, and is used when determining the percentage of the compound containing imide groups not taken into account; the specification relates to 0.1 to 20 wt

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themselves, only on the combination connection with imide groups and Styrene.

The definitions given in formula I for the substituent R and the index η represent mean values; you can use both compounds that contain an integer number of imide groups, such as monoimides or bis-imides, or mixtures of such products, these mixtures either specifically with regard to the copolymers according to the invention have been produced or arise in the production of the compounds containing imide groups themselves.

As just said, the connection with imide grouping selected from the monoimides and / or bisimides will.

The monoimides can be given by the general formula II

CO

are reproduced, in which D has the above meaning and R .. is a linear or branched alkyl or alkenyl group with up to 20 carbon atoms, a cycloalkyl group with 5 or 6 carbon atoms in the ring, a mono- or bicyclic group Aryl group or aralkyl group with up to 20 carbon atoms, one of the groups

represents or a monovalent group consisting of a phenyl group and a phenylene group mutually exclusive by a single bond or by an atom or a group which is inert under the reaction conditions, such as -0-, -S-, alkylene group with 1 to 3 carbon atoms,

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-GO-, -SO ₂ -, -NR _4- - * -N = N-, -CONH-, -GOO-, where R ^ for H, OH · ,, represents the phenyl group or the cyclohexyl group. In addition, these different groups can still be through, one or more atoms, groups or groupings, such as F, Cl, CH ₅ , OCH ₅ , OG ₂ H ₅ , OH, NO ₂ , -COOH, -NHCOOH ₅ ,

CO- CII-OCOCH

-N I

CO - CH ₂

be substituted.

Examples of monoimides of the general formula II are N-phenyl maleic acid imide, N-phenylmethyl maleic acid imide, N-phenylchloromaleimide, N-p-chlorophenylmaleimide, N-p-methoxyphenyl maleic acid imide, N-p-methylphenyl maleic acid imide, N-p-nitrophenyl maleic acid imide, N-p-phenoxyphenyl maleic acid imide. N-p-phenylcarbonylphenyl maleic acid imide, 1-maleic acid imido-4-acetoxysuccinic acid imidobenzene, 4-maleic acid imido-4'-acetoxysuccinic acid imidodiphenyl methane, 4-maleic acid imido-4'-acetoxysuccinic acid

/ imidoimido-diphenyl ether, 4- maleic acid 4'-acetamidodiphenyl ether, 2-maleic acid imido-6-aceta.midopyridine, 4-maleic acid eimido-4'-acetamidodiphenylmethane, N-methyl maleic acid imide, N-ethylraaleimide, N-yinylmaleimide, N-allylmaleimide, N-cyclohexyl maleic acid imide and N-decyl maleic acid imide.

These monoimides can be used, for example, in US Pat. Nos. 2,444,538, 3,717,615 or in DE-OS 2,354,654 methods described.

The compound having an imide grouping can also be a bis-imide of the general formula III

Ti ^ NAN, D

\ ⁷

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/ ρη

be, in which D has the meaning given above and A stands for one of the following divalent groups: Linear or branched alkylene groups with 2 to 12 carbon atoms, Phenylene, cyclohexylene, cyclopentylene, biphenylene or naphthylene group,

NH

N-C

^ ⁰¹ Vp-t It- ^(CH 2> -

where ρ is an integer from 1 to 3 and Z is a Is a single bond or an alkylene group having 1 to 12 carbon atoms,

the groups consisting of at least two alkylene groups which are linked to one another by an atom or a group such as -0- or -NR ₂ >,

the groups consisting of at least two phenylene or cyclohexylene groups which are bonded to one another directly or via an atom or a group which is inert under the conditions of the copolymerization, such as -0-, -S-, an alkylene group with 1 to 3 carbon atoms, -CO -, -SOp-, -NR ₂ -, -N = N-, -CONH-, -COO-, -P (O) R ₂ , -CONH-X-NHCO-,

- ¹

-N

N-N

N-N

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whereby

H _{2 represents} a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, the phenyl or cyclohexyl group, and X is an alkylene group having 1 to 12 carbon atoms.

Examples of such bis-imides are: NjN'-ethylene-bis-maleic acid imide, N, N'-m-phenylene-bis-maleic acid imide, Ν, Ν'-hexamethylene-bis-maleic acid imide, N, N'-p-ehenylene- bis-maleic acid imide, N, N ^l -4.4 ^l -Biphenylen-bis-maleic acid imide, N, N ¹ -4 »4'-diphenylmethane-bis-maleic acid imide, N, N'-4,4 ¹ -diphenylmethane-bis- tetrahydrophthalimide, N, N ^l -4,4 ¹ -Diphenyläther-bis-maleic acid imide, N, N ^I -4,4 ^I -diphenylsulfid.-bis-maleic acid imide, N, N ^l -4i4'-I> iphenylsulfon-bis-maleic acid imide , N, N ^l -4.4 ^l -Bicyclohexylmethan-bis-maleic acid imide, NjN'-Ofj ^ '^^' - Dimethylene-cyclohexan-bis-maleic acid imide, N, N'-p-xylylene-l3is-maleic acid imide, N, N'-4,4'-Diphenyl-1, i-cyclohexane-bis-maleic acid imide, N, N'-4,4 ^U diphenylmethane-bis-citraconimide, N, N ¹ ^^ '-diphenyl ether-bis-endomethylene-tetrahydrophthalimide , N, N ^l -4,4 ^f -diphenylmethane-bis-chloromaleimide, N, N'-4,4 ¹ -diphenyl-1,1-propane-bis-maleic acid imide, N, N'-4 j 4 * -triphenyl -1,1,1-ethane-bis-maleic acid imide, N, N'-4,4'-triphenylmethane-bis-maleic acid imid, N, N'-3,5-triazole-1,2,4-bis-maleic acid imide, !!, N'-dodecamethylene-bis-maleic acid imide, N, N ¹ -trimethyl-2,2,4-hexamethylene- bis-maleic acid imide, bia- (2-maleic acid imido-ethoxy) -1,2-ethane, bis-0-maleic acid imido-propoxy) -1,3-propane, NjN '^^' - benzophenone-bis-maleic acid imide,

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li, N ^l -pyridir] diyl-2,6-bis-maleic acid imide,! [, N'-naphthylene-1,5-bis-maleic acid imide, K, N ^! -Cyclohexylene-1,4-bis-maleic acid imide, NjN'-methyl ^ -phenylen-i, 3-bis-maleic acid imide, N,!} ^1- methoxy-5-phenylene-1,3-bis-maleic acid imide.

These bis-imides can be prepared using the methods described in US Pat. No. 3,018,290 and British Pat. No. 1,137,592 getting produced.

The compound with imide grouping can also consist of one or more products containing 3 to 5 imide groups, exist. In this case the substituent R in the general formula I can contain up to 50 carbon atoms and consist of a naphthalene, pyridine or triazine ring, a benzene ring with 1 to 3 methyl groups is substituted, or from several benzene rings, which are mutually via an atom or one group inert under the reaction conditions, as indicated above, or above

—_N-,, ~ =: CH-, -0-P (O) O- • I O-

are bound.

Examples of such polyimides are products of the general formula

in which D has the meaning given above, y is a any number from about 0.1 to 4 and R, for a divalent hydrocarbon group with 1 to 8 carbon

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atoms is derived from an aldehyde or a ketone of the general formula 0 = R- ^, in which the oxygen atom is bonded to a carbon atom of the substituent iU. The manufacture of such Polyimides are described in BE-PS 785 391, for example.

The invention also relates to a process for the production of copolymers from styrene and compounds with imide moiety (s) as defined.

This process is characterized in that the compound is used in the polymerization of the monomeric styrene with imide grouping is continuously added to the polymerization medium during the polymerization of the styrene.

In general, the copolymerization at a temperature in the range of 50 to 150 C, preferably in the range of 70 to 120 ⁰ C.

The copolymerization reaction between styrene and the connection with imide grouping (s) is generally carried out in the presence of one or more polymerization initiators. When carrying out the process according to the invention, those customary for the polymerization of styrene can be used Use initiators. Such initiators are generally selected from the radical-forming compounds, for example organic peroxides, such as dicumyl peroxide, benzoyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di (tert-butyl) peroxyhexyne-3, lauroyl peroxide or azo compounds, such as azo-bis-isobutyronitrile or persulfates, such as potassium or ammonium persulfate, or redox systems with two components (e.g. peroxides and ferrous salts).

The polymerization can also be started thermally.

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The choice of initiator depends on its decomposition temperature and on the selected polymerization temperature. The amount of initiator is generally from 0.01 to 3 Parts per 100 parts of styrene. Depending on the chosen procedure for carrying out the copolymerization reaction the initiator is used as such or in diluted form in a solvent.

Copolymerization of styrene and compound with imide grouping (s) can be carried out in various ways are: as bulk polymerisation, as solution polymerisation, as emulsion polymerisation or as suspension polymerisation. In view of the fact that the compound with imide group (s) gradually * is added, is preferably carried out in the liquid phase, i.e. in solution or in emulsion or in Suspension polymerized.

*respectively. ongoing

When working in a solvent medium, compounds are chosen that are compatible with both styrene and are solvents for the imide compound. Examples of such solvents are dioxane, dimethylformamide, Dimethylacetamide, N-methylpyrrolidone, tetrahydrofuran and Toluene in the heat, whereby also styrene itself for the preparation of a solution of certain compounds with imide grouping (s) can be used.

When working in the solvent medium, a solution of the monomeric styrene is first prepared and then after Setting the further reaction conditions, such as temperature and initiator described above, the connection with Imide group (s) also added in the form of a solution. Of course, in this case to produce the Both solutions use the same solvent or two different solvents can be used lead to mutually miscible solutions.

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The concentration of the solutions of the monomeric styrene is generally from 5 to 95% by weight of styrene, based on the weight of the solution; the concentration of the solution of the compound with imide group (s) can be 0.1 to 50 ° ß> .

As already indicated, according to a variant of the method, the reaction in the absence of an additional Compound, which serves as a solvent, can be carried out if, on the one hand, styrene as such uno. on the other hand a solution of the compound with imide group (s) in styrene is used.

The emulsion or suspension polymerization is generally carried out in an aqueous medium. According to the customary procedures styrene in the presence of a surface-active Emulsified by means of. This surfactant can be nonionic, anionic or be cationic compound. Examples of such compounds, which are generally used in a ratio of 0.1 to 10 Parts per 100 parts of styrene are used: as non-ionic compounds: polyvinyl alcohols, polyacrylates, Copolymers of ethylene and propylene; as anionic compounds: fatty acid salts, such as sodium stearate, Potassium lauryl sulfate, sodium dodecylbenzenesulfonate, Sodium and potassium alkyl naphthalene sulfonates; as cationic compounds: quaternary ammonium salts, Pyridine derivatives such as alkyl pyridinium compounds.

When polymerizing in emulsion or in suspension, the compound ^z wSrden the compounds with imide group (s), depending on their nature, are dispersed in the form of a powder in the styrene emulsion or in turn used in the form of a suspension or emulsion. In this case, a surface active agent such as one of the above-mentioned compounds can be used.

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As already indicated, the essential feature of the process according to the invention for the preparation of copolymers based on styrene and a compound with imide grouping (s) is that this compound is introduced into the medium for the polymerization of styrene in the course of this polymerization. This means that it is important that the reaction medium does not contain the total amount of the compound (s) with imide group (s) before the start of the polymerization of the styrene. It also means that this compound with imide grouping (s) should be introduced into the polymerization medium while this polymerization is in progress and not when the styrene present in the medium has reached the desired degree of conversion or polymerization. Within the limits given, it is up to the person skilled in the art to choose the most convenient and advantageous mode of operation: introduction of the compound with imide group (s) in a rigorously constant manner, for example with the aid of a metering pump with controllable throughput; Introduce in small portions, for example with the help of a drip device. In general, it is desirable to start introducing the imide grouped compound (s) as soon as the styrene is under the conditions defined above to allow its polymerization and to control the rate of addition so that the total amount of the imide grouped compound (en) is introduced into the polymerization medium for a period of time which is about 70 to 90 f of the total duration of the copolymerization reaction.

After the end of the copolymerization, this is obtained Polymer further treated as usual, i.e. precipitated from the solution or emulsion, filtered, washed and dried.

The copolymers produced according to the invention are obtained as powder or as granules and can be used for production of molded bodies under the usual conditions for thermoplastic polymers, in particular polystyrene

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be used. They are particularly suitable, wherein for press-molding a temperature of generally 150 to 210 ⁰ C under a pressure of 20 to 400 bar, as well as for injection molding under the same conditions of temperature and pressure.

The copolymers are also suitable for the production of materials with a light structure, i.e. cellular ones Substances, by using the methods customary in the field of polystyrene for this purpose.

The copolymers prepared according to the invention are distinguished from polystyrene by a significant increase in the glass transition temperature or the freezing range (determined on powder by means of differential thermal analysis with a temperature rise rate of 10 C / min, after the thermal history of the product has been extinguished). An increase in the softening temperature according to YICAT, determined on compression-molded test specimens under a load of 5 kg at a temperature increase of 50 ° C./h in accordance with the French EOrm NI ¹ T 51 021, is also observed. It is surprising to find that this improvement of Properties, glass transition or second-order phase transformation and softening according to VICAT is very clearly pronounced, even with very little compounds) with imide grouping (s).

The copolymers prepared according to the invention can be used in the various fields of application for polystyrene used. Due to their improved properties, they are particularly suitable for manufacturing of workpieces or products for electrical household appliances, for example products for the protection of Electric motors in the manufacture of household appliances, protective housings in the manufacture of televisions, Workpieces for thermal insulation and parts of fittings.

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The following examples serve to provide a more detailed explanation the invention:

Examples 1 to 4

In a glass reactor with a stirrer, a temperature measuring device, a cooler and a feed funnel was provided, 300 ml of dioxane, 100 g of styrene and 2.4 g of benzoyl peroxide were submitted.

A solution of 1 g
N, N ¹ , 4>4'-Diphenylmetliane-bis-maleic acid imide in 200 ml
Given dioxane.

The contents of the flask increased over the course of 25 minutes
80 ⁰ O brought. Then the bis-maleimide solution was continuously introduced into the polymerization medium. The total amount of the solution was added after 4 hours. The temperature of the reaction mass was then maintained for a further hour. The polymer was then poured into 5 l of methanol with vigorous stirring, and the precipitate was filtered off, washed and dried at 60.degree. C. under a reduced pressure of 20 mm Hg. 39 g of a fine one were obtained
white powder.

The number average molecular weight of the copolymer was 14,000.

The glass transition temperature (Tg), determined by means of
Differential thermal analysis under the above conditions was 101 ⁰ G.

The above procedures were repeated using different amounts of N, N ¹ , 4,4'-diphenylmethane-bis-maleimide.

The following table shows the test conditions and results for the various approaches: Weight of added monomers (bis-male

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to

acid imide, and styrene), degree of conversion of the styrene percentage, proportion of the bis-maleimide units in the copolymer (wt -. ° / o bis-imide copolymerized in the copolymer), Tg GIasubergangstemperatür and VICAT softening temperature.

For comparison, a styrene homopolymer was included same conditions without the addition of bis-maleimide manufactured.

The uniform distribution of the bis-maleimide compound groups inside the copolymer was demonstrated by repeating the experiment of Example 3, but with the entire amount of bis-maleimide was added at the beginning of the polymerization, only a very slight improvement in the glass transition temperature, based on the homopolymer, was observed (96 C versus 92 C) while in Example 3 the Temperature Tg is 112 ° C.

Tabel 1 See you
acid imide
G Styrene
G Styrene
conversion See you
acid imide
in poly
merisat Day
° c Vicat
Temp.
⁰ C 1 100 38 2.6 101 102 example 2.5 100 42 5.6 98.5 1 3 100 40 7.0 112 111 2 5 100 41 11.0 115 113 3 4th

Comparison 0 100 45 0 92 93

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Example 5

In a glass reaction vessel with a stirrer, cooler, Thermometer and feed funnel with a tight stirrer was equipped, 200 ml of dist. Water, 0.1 g potassium persulfate, 0.1 g disodium phosphate and 2 g a nonionic surfactant of the polyol type presented.

This solution was homogenized} 100 g of styrene were then added with stirring and emulsified in the water.

First 100 ml of water, 0.05 g of disodium phosphate, 1 g of the above emulsifier and ^{5 g of N, W, 4> 4 l} -diphenylmethane-bis-maleic acid imide were placed in the inlet funnel and a fine suspension or microsuspension was generated by vigorous stirring. Vigorous agitation was continued during the following operations.

The reaction vessel was heated ^{to 70 °} C. in the course of 10 min. Half of the suspension was then gradually run in or added dropwise over the course of 2 hours. To. The temperature was increased to 90 ^° C. for 2 h at 70 ^° C. and the remainder of the suspension was again added over the course of 2 h. The polymerization mixture was then for a further 1 h. held at 90 ^° C.

The copolymer was then, as described in Example 1, isolated.

The degree of conversion for styrene was $ 98 and the glass transition temperature Tg of the copolymer was 102 ^° C.

Example 6

Example 3 was made with N-phenylmaleimide under otherwise the same conditions repeated.

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The isolated copolymer contained 7 ^c ß> units of the imide compound; its glass transition temperature Tg was 104 ° G.

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Claims (10)

Claims Styrene polymers with improved thermal properties, characterized in that they are made from copolymers of styrene and a compound with imide groups of the general formula I. CO τ /. ^X N exist, in which η is a number from 1 to 5, R for an organic group of valence η with 2 to 50 carbon atoms and D is one of the groups where Y is H, CEU or Cl and m is O, 1 or 2 is 909821/0581 and that the copolymers 0.1 to 20 wt .- ^ compound with imide grouping in polymerized form and the units of this compound regularly in those of styrene formed chains are distributed. 2. styrene polymers according to. Claim 1, characterized characterized in that starting from a bis-imide of the general formula III D N-A-F D III have been prepared, in which D has the meaning given in claim 1 and A for one of the following two valued groups: linear or branched alkylene groups with 2 to 12 carbon atoms, .Phenylene, cyclohexylene, cyclopentylene, biphenylene or naphthylene group, where ρ is an integer from 1 to 3 and Z is a single bond or is an alkylene group having 1 to 12 carbon atoms, Groups consisting of at least two alkylene groups which are bonded to one another via an atom or a group such as -0- or -NR ₂ , Groups consisting of at least two phenylene or cyclohexylene groups that are bonded to one another by a single bond or via an atom or a group which is inert under the copolymerization conditions, such as -0-, -S-, an alkylene group with 1 to 3 carbon atoms, -CO- , -SO ₂ -, -NR ₂ -, -N = N-, -CONH-, -COO-, -P (O) R ₂ , -CONH-X-NHCO-, 909821/0581 1A-51 495 N-NO N-N Nile where Rp is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms or a phenyl or cyclohexyl group and X is an alkylene group Means 1 to 12 carbon atoms. 3. styrene polymers according to claim 1, characterized g e indicates that they are starting from a Monoimide compound of the general formula II CO II have been prepared, in which D has the meaning given in claim 1 and R- is a linear or branched one Alkyl or alkenyl group with up to 20 carbon 909821 / 0S81 1A-51 atoms, a cycloalkyl group with 5 or 6 ring carbons substance atoms, a mono- or bicyclic aryl group or aralkyl group with up to 20 carbon atoms or for one of the groups or represents a monovalent group consisting of a phenyl group and a phenylene group, which are mutually linked by a single bond or via an atom or an inert group such as -0-, -S-, an alkylene group with 1 to 5 carbon atoms, -CO-, -SO ₂ -, -ITR.-, -N = K-, -CONH-, -COO-, where R. is H, CH ,, the phenyl or the cyclohexyl group, are bonded. 4. styrene polymers according to claim 1, characterized in that they are starting from a Mixture of bis-imide compound according to Claim 2 and monoimide compound according to claim 3 have been produced. 5. Process for the preparation of the styrene polymers according to one of claims 1 to 4, characterized in that after the conditions for the polymerization of styrene has ceased, the imide compound gradually adds in the course of the polymerization. 6. The method according to claim 5, characterized in that the copolymerization is carried out in the presence a polymerization initiator. 7. The method according to claim 6, characterized in that g e k e η η that a radical-forming compound is used as the polymerization initiator. 909821/0581 ■ ■■ ■. - b - 1A-51 495 8. The method according to any one of claims 5 to 7, characterized in that the copolymerization in the presence of a solvent for
Styrene and the imide compound performs. 9. The method according to any one of claims 5 Ms 7, characterized characterized in that the imide compound is added to the polymerization medium in the form of its solution in styrene clogs. 10. The method according to any one of claims 5 to 7, characterized characterized in that the copolymerization of styrene and imide group-containing compound carried out in emulsion or in suspension. 909821/0581