Process for preparation of modified polyphenylene ether or related polymers and the use thereof in modified high temperature rigid polymers of vinyl substituted aromatics

Abstract: Process for the manufacture of modified polyphenyl ether or structurally related polymers comprising the reaction of said compound with a para substituted phenylsulphonyl halide, in the presence of a substituted pyridine derivative as catalyst and an acid neutralizing agent, and in a vinyl substituted aromatic monomer as solvent; modified polyphenylene ethers or structurally related polymers so obtained and use of them for the manufacture of modified high temperature rigid poly(vinyl substituted aromatic) polymer compositions.

Description: The invention relates to a process for the preparation of modified polyphenylene ether or related polymers and to the use thereof in modified high temperature rigid polymers of vinyl substituted aromatics. More particularly the invention relates to an improved process for the preparation of modified polyphenylene ether or structurally related polymers by capping the residual free hydroxy groups in such compounds by reaction with an acid derivative. Blends of polymers of vinyl substituted aromatics and poly(2,6-dimethyl-1,4-phenylene ether) further on to be indicated by PPE, or structurally related polymers and more particularly blends of polystyrene and PPE have been aimed at for a long time. However, the polymerization of vinyl substituted aromatics in the presence of PPE was found to be prohibited or inhibited, which causes lower polymerization yields of the vinyl substituted aromatic monomer and more particularly when the PPE is used in a large amount there are some cases where the polymerization does not progress at all. Accordingly, no substantial polymerization could be progressed unless the PPE was used in an amount as small as possible to make the concentration of the vinyl substituted aromatic compound higher. This phenomenon was especially observed in the case where a vinyl substituted aromatic, and more particularly styrene, was polymerized in an aqueous dispersion in the presence of PPE and optionally a rubber component. Several processes were proposed in the past such as those described in Japanese patent application No. 22069/67; Dutch patent application No. 6617529; French patent No. 1,551,503, using large excesses of styrene as to the PPE. A common feature of all these processes was that in order to decrease the styrene content of the polymerization product, it was necessary to lower polymerization yield. In the case of polymerization of e.g. styrene in a suspension system there was observed a phenomenon, that even if the styrene content of the polymerization is intended to be decreased by lowering the polymerization yield, a large amount of unreacted styrene remains in the polymerization product. The unreacted monomer relatively high in boiling point, which was contained in such beads, was found to be difficultly removed by drying, with the result that a moulded article obtained from the polymerization product was greatly injured in appearance and was also deteriorated in physical properties. In order to avoid these disadvantages, several remedies were proposed in the past such as described in e.g. U.S. patent No. 3,862,263, proposing a process, in which a relatively small amount of a styrene compound is substantially completely graft polymerized on PPE, optionally mixed with an elastomeric polymer, and as described in U.S. patent No. 4,287,321 disclosing the preparation of PPE-poly(vinyl aromatic) compositions by oxidatively coupling a phenol dissolved in a basic reaction medium, comprising a vinyl aromatic compound in the presence of a manganese chelate catalyst, selectively extracting base-reactive by-products, and then thermally polymerizing the vinyl aromatic compound. As another remedy to avoid the hereinbefore described difficulties, processes were proposed for capping the starting PPE by conversion of the remaining free hydroxyl groups in said PPE with a material capable of reacting therewith to form inert substituents in a mutual solvent such as aromatic solvents like toluene, benzene. Typical examples of such capping agents include acid halides, acid anhydrides or ketenes as disclosed in e.g. European patent applications Nos. 0,261,574 and 0,264,623 and U.S. patents Nos. 4,048,143; 4,189,417; 4,156,773; and 4,165,422. Although this capping process was known in principle for some time, a rather extensive research for improved and more economical embodiments has still continued, an important part of the efforts being directed to the application of improved alternative capping agents, as appears e.g. from German patent application No. 3,238,930, U.S. patent No. 4,743,661 and the International patent application WO 83/02117. Although some of the hereinbefore described processes could indeed provide some progress in the art, there remained a strong need for polymer blends which are obtainable by an economically attractive process for polymerization of a vinyl substituted aromatic monomer in the presence of relatively large amounts of PPE, to be incorporated in the final polymer blends, showing the desired improved characteristics such as high temperature rigidity, and more particularly final polymer blends representing interpenetrating networks. More particularly there is still a need for an economical manufacturing process for the preparation of modified PPE, which can successfully be applied for the manufacture of blends of (a) polymer(s) of vinyl substituted aromatic monomers and said modified PPE in order to get modified high temperature rigid compositions aimed at. With the term "modified high temperature rigid compositions" as used throughout the present specification are meant compositions, which show a higher glass transition temperature (Tg) as compared with conventional compositions and as a consequence a higher Vicat softening point e.g. measured according Vicat B DIN 53460. As a result of extensive research and experimentation there is now surprisingly found a process for the manufacture of modified polyphenylene ether or structurally related polymers, comprising the reaction of a compound of the formula: wherein R 1 and R 4 each may represent hydrogen, halogen, a phenyl group, alkenyl group, alkadienyl group, an aryloxy group, or wherein R 1 and R 4 each may represent an alkyl group or an alkoxy group, each of the latter containing 12 or less carbon atoms and each optionally substituted by halogen, cyano, hydroxy, phenyl or amino, whereas alkyl or alkoxy groups attached to the terminal phenol nucleus of the chain may be substituted by an amino, dialkylamino or a di(alkanoyl) amide group, wherein the alkyl groups each contain 4 or less carbon atoms, wherein R 2 and R 3 each may represent hydrogen, halogen, a phenyl group, alkenyl group, alkadienyl group, aryloxy group or wherein R 2 and R 3 each may represent a primary or secondary alkyl group or alkoxy group as defined for R 1 and R 4 , optionally substituted by halogen, cyano, hydroxy, phenyl,-and wherein R 1 , R 2 , R 3 and R 4 may represent different or the same groups in one repeating unit, and n represents an integer having a value of at least 50 and more preferably 100 to 500, with a para substituted phenylsulphonyl halide of the general formula: wherein X 1 represents halogen or an alkyl group containing 1-4 carbon atoms and more prefereably 1 or 2, and which may optionally be substituted by halogen, and wherein X 2 represents halogen, in the presence of a catalyst of the formula: wherein R 5 and R 6 both represent in general non-electron withdrawing groups such as alkyl groups containing from 1 to 4 carbon atoms, optionally substituted by at most one phenyl group and wherein the symbols R 7 and R 8 represent hydrogen, halogen or lower alkyl, while R 5 and R 6 , R 7 and R 8 may represent different or the same groups in one molecule, and an acid neutralizing agent, and in a vinyl substituted aromatic monomer as solvent. Typical examples of the polyphenylene ether or structurally related polymers to be applied for the process of the present invention, include poly-2,6-dimethyl-1,4-phenylene ether (PPE); poly-2,6-diethyl-1,4-phenylene ether; poly-2,6-dipropyl-1,4-phenylene ether; poly-2-methyl-6-allyl-1,4-phenylene ether; poly-di-tert-butyl-dimethoxy-1,4-phenylene ether; poly-2,6-dichloromethyl-1,4-phenylene ether,poly-2,6-dibromomethyl-1,4-phenylene ether; poly-2,6-di(2-chloroethyl)-1,4-phenylene ether; poly-2,6-ditolyl-1,4-phenylene ether; poly-2,6-dichloro-1,4-phenylene ether: poly-2,6-diphenyl-1,4-phenylene ether and poly-2,5-dimethyl-1,4-phenylene ether. Preferably the symbols R 1 , R 2 , R 3 and R 4 in formula I represent hydrogen or an optionally substituted alkyl, containing from 1 to 4 carbon atoms and more particularly R 1 and R 4 may represent, when attached to the terminal phenol nucleus of the polyphenylene ether chain, an aminoalkyl or a (dialkylamino) alkyl group, the alkyl groups of which are containing from 1 to 4 carbon atoms. More preferably the symbols R 1 , R 2 , R 3 and R 4 are selected from hydrogen and methyl, optionally substituted as defined hereinbefore, whereas R 1 and R 4 may represent when attached to the terminal phenol nucleus of the chain, an aminomethyl or a (dialkylamino)methyl group, the alkyl groups of which are containing of from 1 to 4 carbon atoms, e.g. di(n-butyl)amino. Even more preferably, R 1 and R 4 represent both methyl and R 2 and R 3 represent both hydrogen. The most preferred embodiment of the starting compounds according to formula I is poly-2,6-dimethyl-1,4-phenylene ether, wherein one or both of the methyl groups attached to the terminal phenol nucleus of the chain, have been substituted by an amino or dialkylamino group, the alkyl groups of which are containing of from 1 to 4 carbon atoms. Preferred para substituted phenylsulphonyl halides to be used as capping agents are those wherein X 1 represents bromine or a methyl or ethyl group substituted by bromine, and wherein X 2 represents bromine or chlorine. Most preferably para-bromophenylphenylsulphonyl chloride (brosylchloride) or para-bromomethylphenylsulphonyl chloride is used as capping agent. In the catalyst according to formula III, the symbols R 5 and R 6 preferably represent both methyl groups or ethyl groups, whereas R 7 and R 8 preferably represent hydrogen, chlorine or a methyl group. Most preferably N,N-dimethyl-4-amino pyridine (DMAP) is used as catalyst. As acid neutralizing agent may be used in principle any basic compound which may sufficiently dissolve in the reaction medium. More particularly an organic base is used such as N,N′-di(t-butyl)ethylenediamine, N,N-dimethylbutylamine, di(n-butyl)amine, triethylamine, diethylamine, picoline, quinoline, pyridines, pyrimidines, quinoxalines, tri-n-propylamine, triisopropylamine, dimethylisopropylamine and the like, of which triethylamine or tri-n-propylamine are preferred. It will be appreciated that in the vinyl substituted aromatic monomer optionally one or more elastomeric homopolymers or copolymers may be included. More particularly homopolymers or copolymers of a vinyl substituted aromatic monomer and/or a conjugated diene monomer may be included. Preferably block copolymers AB or ABA comprising a block of vinyl substituted aromatic monomer (A) and a block of conjugated diene (B) such as polystyrene and polybutadiene or polyisoprene blocks may be used. More preferably partially hydrogenated and/or modified block copolymers of a vinyl substituted aromatic monomer and conjugated diene may be included. Suitable examples of elastomeric polymers may be selected from polybutadiene, polyisoprene (including natural rubber), polychloroprene, butadiene-styrene random or block copolymers, prepared by emulsion or solution polymerization, polyisoprene-styrene random or block copolymers and polychloroprene-styrene random or block copolymers. Such included elastomeric polymers have appeared to improve the impact strength. The vinyl substituted aromatic monomer may be selected from the group consisting of styrene, α-methyl styrene, 2,4-dichlorostyrene, p-methoxystyrene, p-nitrostyrene, p-methylstyrene, 3,4-dimethylstyrene, m-tert-butylstyrene, p-dodecylstyrene, p-phenylstyrene, p-acetoxystyrene, divinylbenzene, p-aminostyrene, p-(chloromethyl)-styrene, m-cyanostyrene, o-hydroxystyrene, p-vinylbenzoic acid, α-propylstyrene, α-undecylstyrene, o-methyl-α-methylstyrene, m-methyl-α-methylstyrene, p-methyl-α-methylstyrene, p-methoxy-α-methylstyrene, p-cyano-α-methylstyrene, m-bromo-α-methylstyrene, p-chloro-α-methylstyrene and 1,1-diphenylethylene or mixtures thereof of which styrene alone or predominantly styrene containing monomer mixtures being preferred. It will be appreciated that in the event that R 1 , R 2 , R 3 or R 4 represent a substituent containing a hydroxyl group, a corresponding excess amount of the para substituted phenylsulphonyl halide is used. The vinyl substituted aromatic monomer itself and more preferably styrene, or mixtures of them is used as solvent for the preparation of the modified PPE or structurally related polymer. During this conversion a reaction temperature is applied in the range of from 0 to 60 °C and more preferably from 10 to 30 °C. According to a preferred embodiment of the process of the present invention for preparation of capped PPE or structurally related polymer, an amount of 5-50% by weight of e.g. unmodified PPE calculated on the weight of the complete reaction mixture, is converted. However, in principle higher concentrations of unmodified PPE or structurally related polymer may be converted too, whereafter the obtained reaction mixture may be diluted with additional vinyl substituted aromatic monomer to the desired concentration of PPE, before starting the polymerization process. On the other hand, one can also prepare low concentration PPE solutions in vinyl substituted aromatic monomer and remove a part of this monomer by evaporation to obtain the desired concentration of PPE. More preferably unmodified PPE or a structurally related polymer is used in the starting mixture in a concentration of 30-50% by weight. With the term "unmodified PPE or structurally related polymers", as used throughout the present specification, is meant polymers, having terminal free hydroxy groups. During the conversion of unmodified PPE or structurally related polymer, the catalyst may be used in a concentration in the starting reaction mixture of from 0.0025-0.1% by weight and preferably of from 0.01 to 0.075% by weight, calculated on the weight of the complete reaction mixture. The para substituted phenylsulphonyl halides according to formula II may be used in a concentration in the starting reaction mixture, e.g. in styrene, of from 0.05 to 0.5% by weight and more preferably from 0.1 to 0.3% by weight, calculated on the weight of the complete reaction mixture. The hereinbefore specified acid neutralizing agent may be used in amounts being at least equivalent to the amount of acid to be produced during the conversion of desired amount of unmodified PPE or structurally related polymer and will normally be in the range of from 0.05 to 5.0% by weight and more preferably from 0.1 to 0.3% by weight, calculated on the weight of the complete reaction mixture. It will be appreciated that according to the present conversion process of unmodified PPE or structurally related polymer, bearing terminal free hydroxy groups, modified PPE or structurally related polymer is quickly and efficiently obtained as compared with prior art processes. The product shows characteristic infrared absorption maxima, from which the characteristic maxima which normally may be attributed to the presence of any free hydroxy group (3447 cm -1 ), have disappeared to a substantially neglectable level, whereas the other characteristic maxima, originally found for the starting PPE, being not attributable to hydroxy groups, have remained. Moreover, a novel characteristic Fourier transformed infrared absorption maximum is e.g. found at 729 cm -1 , as shown in figure 1 for PPE converted with bromotosyl chlorides as compared with normal PPE, after isolation by precipitation in methanol at room temperature. It will be appreciated that another aspect of the present invention is formed by the use of the modified PPE or a structurally related polymer for the manufacture of modified polymers of vinyl substituted aromatics by means of several polymerization methods, dependent on the finally desired application of said compositions. Accordingly the present invention is also relating to a process for the manufacture of modified high temperature rigid poly(vinyl substituted aromatic) compositions, comprising the polymerization of a vinyl substituted aromatic monomer in the presence of modified polyphenylene ether or a structurally related polymer, obtainable by a previous reaction of a compound of the formula wherein R 1 , R 2 , R 3 and R 4 are as defined hereinbefore, with a para substituted phenylsulphonyl halide according to formula: wherein X 1 and X 2 are as defined hereinbefore in the presence of a catalyst of the formula wherein R 5 , R 6 , R 7 and R 8 are as defined before and an acid neutralizing agent, and in the vinyl substituted aromatic monomer as solvent. It will be appreciated by persons skilled in the art that such a process enables an economically very attractive manufacture of the desired vinyl substituted aromatic polymers, modified by the incorporation of PPE or structurally related polymer. For example beads of modified polymers of vinyl substituted aromatics may be prepared by aqueous suspension polymerization. Such beads may be optionally impregnated by a physically and/or chemically blowing agent during or after the polymerization process. Such beads may be applied for e.g. injection moulding, extrusion etc., to prepare a great variety of engineering plastics when non-impregnated beads are used, and may be applied in impregnated expandable forms to prepare a great variety of engineering foams. It will be appreciated that the polymerization of the vinyl substituted aromatic monomer, containing the modified (capped) PPE or structurally related polymer may also be carried out as bulk polymerization, optionally in the presence of usual auxiliaries, such as fillers, fibres or non-woven webs, dyes, stabilizers or flame retardants, to form shaped articles. Especially the manufacture of thermoplastic matrix polymer compositions, having a specifically desired shape, was not possible up to now. Therefore, it is an unexpected advantage of the process of the present invention that such shaped thermoplastic matrix polymers are provided now. It was found that the modified PPE or structurally related polymer could be incorporated in situ into the polymer compositions to be formed during polymerization of the vinyl substituted aromatic in a sufficiently effective amount and in an economically attractive way. More particularly the modified PPE or structurally related polymer could be incorporated in an economically attractive way, into beads of polymers of the vinyl substituted aromatics and more preferably styrene, which are formed during aqueous suspension polymerization of such monomers. With the term "in a sufficiently effective amount" as used throughout the present specification, is meant to indicate that the modified PPE or structurally related polymer can be incorporated in situ during the preparation of these matrix polymer blend beads of the polymer of vinyl substituted aromatic to provide to them the desired heat stability. For example an increase of Tg of the final beads of about 40 °C as compared with beads substantially free of PPE or structurally related polymer, when containing an amount of about 40% by weight of PPE or structurally related polymer, calculated on the weight of the final matrix polymer blend composition. It will be appreciated that in particular the use of para substituted phenylsulphonyl halides according to formula II, wherein bromine is occurring as substituent, will provide fire retarding properties to the finally prepared products of modified polymers of vinyl substituted aromatics, wherein the modified PPE or structurally related polymer has been incorporated. Preferably the modified PPE or structurally related polymer, and more preferably PPE, obtained according to hereinbefore specified conversion, is subsequently used for incorporation into matrix polymer blend beads, to be formed by means of aqueous suspension polymerization to be carried out by methods known in principle. The polymerization process may be carried out in any suitable reactor equipped with heating means and agitating means. The reaction mixture, obtained by the conversion of unmodified PPE or structurally related polymer, is heated for a period of time and a temperature to cause the vinyl substituted aromatic monomer to polymerize. Generally temperatures of from 80°-175 °C may be employed and preferably in the range from 90 to 130 °C for a period of 2 to 10 hours. If temperatures above the boiling point of vinyl substituted aromatic monomer are used or if blowing agents have to be impregnated during polymerization pressure vessels should be used to prevent vaporization. According to a preferred embodiment of the aqueous suspension polymerization, the amount of water may vary from 1 to 10 parts by weight, per part of weight of the reaction mixture containing the modified PPE or structurally related polymer and vinyl substituted aromatic monomer(s) and preferably from 1-2 parts water per part by weight of reaction mixture. The aqueous dispersion to be used contains a dispersion stabilizer and one or more polymerization catalysts. Examples of such dispersion stabilizers include polyvinyl alcohol, gelatine, agar, starch, glycerine, sodium salt of polyacrylic acid and polymethacrylic acid, polyethylene glycol, hydroxyethyl cellulose, carboxymethyl cellulose, methyl cellulose, ethylene glycol, polyacrylamide and 1:1 copolymer of e.g. styrene and maleic anhydride. The amount of the dispersion stabilizer to be used is ordinarily from 0.0001 to 3% by weight and preferably from 0.001 to 1.5% by weight and more preferably 0.01 to 0.7% by weight, based on the weight of the water used. Typical examples of the polymerization catalysts include decanoylperoxide; benzoylperoxide; laurylperoxide; octanoyl- peroxide; stearylperoxide; 3,5,5-trimethylhexanoylperoxide; tert-butylperbenzoate; tert-butylperacetate; tert-butyl- perpivalate; diisopropylphenylhydroperoxide; 2,5-dimethyl-2,5-ditert-butylperoxyhexane; di-tert-butylperoxide; cyclohexanone- peroxide; dicumylperoxide; α,α′-azobis(isobutyronitrile), tert-butylperoxyisobutyrate and tert-butylperoxylaurate. These radical initiators are preferably high temperature decomposing type catalysts or are used in the form of a combination of 2 or more catalysts, e.g. a combination of a low temperature decomposing type catalyst with a high temperature decomposing type catalyst. In case the combination of a low temperature decomposition type catalyst with a high temperature decomposing type catalyst is used, the polymerization is effected initially at below about 90 °C and, after a certain extent of polymerization yield has been attained, the temperature of the system is elevated to carry out the polymerization substantially completely at a high temperature. Preferred combinations of the catalysts used include combinations of lauroylperoxide with dicumylperoxide; lauroyl- peroxide with di-tert-butylperoxide; lauroylperoxide with tert-butylperoxybenzoate; lauroylperoxide with 2,5-dimethyl-2,5-di-tert-butylperoxyhexane; lauroylperoxide with benzoylperoxide; 3,5,5-trimethylhexanoylperoxide with dicumylperoxide; 3,5,5-trimethylhexanoylperoxide with tert-butylperoxybenzoate; 3,5,5-trimethylhexanoylperoxide with benzoylperoxide; 3,5,5-trimethylhexanoylperoxide with di-tert-butylperoxide; tert-butylperoxypivalate with di-tert-butylperoxide; tert-butylperoxypivalate with dicumylperoxide; tert-butylperoxypivalate with tert-butylperoxybenzoate; 2,4-dichlorobenzoylperoxide with tert-butylperoxybenzoate; 2,4-dichlorobenzoylperoxide with dicumylperoxide; 2,4-dichlorobenzoylperoxide with di-tert-butylperoxide; 2,4-dichlorobenzoylperoxide with 2,5-dimethyl-2,5-di-tert-butylperoxy-hexane; octanoylperoxide with dicumylperoxide, octanoylperoxide with di-tert-butylperoxide, and benzoylperoxide with di-tert-butylperoxybenzoate. In the present invention, the catalyst may be used in an amount suitable for polymerization of the vinyl substituted aromatic compound. For adequate practice of the present invention, the catalyst is used in an amount of 0.01 to 1% by weight, preferably 0.3 to 0.7% by weight, based on the weight of the fed monomers. The obtained modified poly(vinyl substituted aromatic) and more preferably polystyrene beads, containing the modified PPE or structurally related polymer, may be impregnated with a blowing agent to provide the desired expandable beads of modified polymer of vinyl substituted aromatic during or after polymerization. The invention is further illustrated by the following examples, however without restriction of its scope to these specific embodiments. EXAMPLE 1 Several polyphenylene ethers [poly(2,6-dimethyl-1,4-phenylene) ether], having a number average molecular weight Mn from 20,000 to 30,000 (e.g. PPE 800 and PPE 808 obtained from General Electric Comp. showing an intrinsic viscosity in chloroform of about 0.48 and 0.42 respectively) were dissolved in styrene in about 1 hr at room temperature in an amount of 30% by weight, based on the weight of the total composition. Subsequently para bromophenylsulphonyl chloride, N,N-dimethyl-4-aminopyridine (DMAP) and triethylamine were added in amounts of 0.1% by weight, 0.01% by weight and 0.1% by weight respectively, calculated on the weight of the total reaction mixture. After one hour stirring at room temperature a small sample of the reaction mixture was precipitated in methanol at room temperature and an infared spectrum was measured as depicted in fig. 1, showing a characteristic maximum at 729.14 cm -1 . Hereafter the temperature was increased to 70 °C and water, containing 0.2% by weight of Natrosol (Registered Trademark) 250 G (I.V. = 350 mPa/sec of 2% aqueous sol measured at 25 °C) of 70 °C was added. Thereafter the obtained suspension was heated to 93 °C during about 5 hours in the presence of dibenzoylperoxide (DBPO), followed by further reaction during three hours at 120 °C in the presence of tert-butylperoxybenzoate (TBPB). Regular spherical beads were obtained, showing a Tg of about 135 °C. These obtained beads were subsequently impregnated with a blowing agent. EXAMPLE 2 Several polyphenylene ethers [poly(2,6-dimethyl-1,4-phenylene) ether] having a number average molecular weight Mn in the range of from 20,000 to 30,000 were dissolved in styrene at room temperature to provide a 10% by weight solution and methylphenylsulphonyl chloride, tri-n-propylamine and DMAP were added in amounts to give concentrations of 0.2%, 0.2% and 0.05% by weight respectively (calculated on the weight of the total reaction system). After stirring for one hour at room temperature the solution was heated to 130 °C and prepolymerized for 1 hr. The solution was then suspended in water containing 0.4% by weight tricalciumphosphate and polymerized in the usual way. This resulted in spherically round beads with a Tg of ± 110 °C. An identical experiment was carried out, using 20% by weight of PPE, except for the pre-polymerization step. After heating to 130 °C the solution was suspended, resulting also in transparent beads with a Tg of ± 120 °C. EXAMPLE 3 Polyphenylene ether (Mn = 25,000) was dissolved in styrene at room temperature to provide a 40% by weight solution and bromo- methylphenylsulphonyl chloride, triethylamine and DMAP were added in amounts to give concentrations of 0.4%, 0.4% and 0.11% by weight respectively calculated on the weight of total reaction mixture. After 1 hr stirring at room temperature a woven fabric (Keflar 49, Registered Trade Mark) was added. Thereafter this sample was heated to 140 °C and polymerized at 90 °C during one hour in the presence of 0.2% by weight of benzoylperoxide, followed by additional polymerization in the presence of tert-butylperoxide in a concentration of 0.3% by weight during 3 hours.

Claims: Process for the manufacture of modified polyphenylene ether or structurally related polymers comprising the reaction of a compound of the formula wherein R 1 and R 4 each may represent hydrogen, halogen, a phenyl group, alkenyl group, alkadienyl group, an aryloxy group or wherein R 1 and R 4 each may represent an alkyl group or an alkoxy group, the alkyl group or alkoxy group containing 12 or less carbon atoms which alkyl group or alkoxy group may optionally be substituted by halogen, cyano, hydroxy, phenyl or amino, whereas alkyl or alkoxy groups attached to the terminal phenol nucleus of the chain may be substituted by an amino, dialkylamino or a di(alkanoyl) amide, wherein the alkyl groups each contain 4 or less carbon atoms, wherein R 2 and R 3 each may represent hydrogen, halogen, a phenyl group, alkenyl group, alkadienyl group, aryloxy or wherein R 2 and R 3 each may represent a primary or secondary alkyl group or alkoxy group as defined for R 1 and R 4 , optionally substituted by halogen, cyano, hydroxy, phenyl, and wherein R 1 , R 2 , R 3 and R 4 may represent different or the same groups in one repeating unit, and n represents an integer having a value of at least 50 and more / preferably 100 to 500, with a para substituted phenylsulphonyl halide of the general formula: wherein X 1 represents halogen or an alkyl group containing 1-4 carbon atoms and more preferably 1 or 2, and which may optionally be substituted by halogen, and wherein X 2 represents halogen, in the presence of a catalyst of the formula: wherein R 5 and R 6 both represent non-electron withdrawing groups such as alkyl groups containing from 1 to 4 carbon atoms, optionally substituted by at most one phenyl group and wherein the symbols R 7 and R 8 represent hydrogen, halogen or lower alkyl, while R 5 , R 6 , R 7 and R 8 may represent different or the same groups in one molecule, and an acid neutralizing agent , and in a vinyl substituted aromatic monomer as solvent, said reaction being conducted at a temperature in the range of from 0 to 60°C. Process according to claim 1, characterized in that R 1 , R 2 , R 3 and R 4 are selected from hydrogen or an optionally substituted alkyl group containing 1 to 4 carbon atoms. Process according to claim 2, characterized in that R 1 and R 4 represent both methyl and R 2 and R 3 represent both hydrogen. Process according to claim 3, characterized in R 1 and/or R 4 represent a di(alkylamino)methyl group in the terminal phenol nucleus in the chain. Process according to any of the claims 1-3, characterized in that para substituted phenylsulphonyl halides are used as capping agent, wherein X 1 represents bromine or a methyl or ethyl group substituted by bromine, and wherein X 2 represents bromine or chlorine. Process according to claim 5, characterized in that para-bromophenylsulphonyl chloride (brosylchloride) or para-bromomethylphenylsulphonyl chloride is used. Process according to any one of the claims 1-6, characterized in that in the catalyst according to formula III, R 5 and R 6 represent both methyl groups or ethyl groups and R 7 and R 8 represent hydrogen, chlorine or a methyl group. Process according to claim 7, characterized in that N,N-dimethyl-4-aminopyridine is used as catalyst. Process according to any one of the claims 1-8, characterized in that as acid neutralizing agent an organic base is used, selected from N,N'-di(tert-butyl)ethylenediamine, N,N-dimethylbutylamine, di(n-butyl)amine, triethylamine, diethylamine, picoline, quinoline, pyridines, pyrimidines, quinoxalines, tri-n-propylamine, triisopropylamine and dimethylisopropylamine. Process according to any one of the claims 1-9, characterized in that one or more elastomeric homopolymers or copolymers are included in the vinyl substituted aromatic monomer. Process according to any one of the claims 1-10, characterized in that styrene is used as solvent. Process according to any one of the claims 1-11, characterized in that the reaction temperature is in the range of from 10 to 30°C. Process according to any one of the claims 1-12, characterized in that polyphenylene ether or a structurally related polymer is used in the starting mixture in a concentration of from 30 to 50%, calculated on the weight of the complete reaction mixture. Process according to any one of the claims 1-13, characterized in that the catalyst is used in a concentration in the range of from 0.0025 to 0.1% by weight, calculated on the weight of the complete reaction mixture. Process according to any one of the claims 1-14, characterized in that the para substituted phenylsulphonyl halide is used in a concentration in the starting reaction mixture of from 0.05 to 0.5% by weight, calculated on the weight of the complete reaction mixture. Process according to any one of the claims 1-15, characterized in that the acid neutralizing agent is used in a concentration of from 0.05 to 5.0% by weight, calculated on the weight of the complete reaction mixture. Process for the manufacture of modified high temperature rigid poly(vinyl substituted aromatic) compositions, comprising the polymerization of a vinyl substituted aromatic monomer acting as a solvent for polyphenylene ether or a structurally related polymer, in-situ modified by a previous reaction at a temperature in the range of from 0 to 60°C of a compound of the formula: wherein R 1 and R 4 each may represent hydrogen, halogen, a phenyl group, alkenyl group, alkadienyl group, an aryloxy group, or wherein R 1 and R 4 each may represent an alkyl group or an alkoxy group, the alkyl group or the alkoxy group containing 12 or less carbon atoms which alkyl group or alkoxy group may optionally be substituted by halogen, cyano, hydroxy, phenyl or amino, whereas alkyl or alkoxy groups attached to the terminal phenol nucleus of the chain may be substituted by an amino, dialkylamino or a di(alkanoyl) amide, wherein the alkyl groups each contain 4 or less carbon atoms, wherein R 2 and R 3 each may represent hydrogen, halogen, a phenyl group, alkenyl group, alkadienyl group, aryloxy group, or wherein R 2 and R 3 each may represent a primary or secondary alkyl group or alkoxy group as defined for R 1 and R 4 , optionally substituted by halogen, cyano, hydroxy, phenyl, and wherein R 1 , R 2 , R 3 and R 4 may represent different or the same groups in one repeating unit, and n represents an integer having a value of at least 50 and more preferably 100 to 500, with a para substituted phenylsulphonyl halide of the general formula: wherein X 1 represents halogen or an alkyl group containing 1-4 carbon atoms and more preferably 1 or 2, and which may optionally be substituted by halogen, and wherein X 2 represents halogen in the presence of a catalyst of the formula: wherein R 5 and R 6 both represent non-electron withdrawing groups such as alkyl groups containing from 1 to 4 carbon atoms, optionally substituted by at most one phenyl group and wherein the symbols R 7 and R 8 represent hydrogen, halogen or lower alkyl, while R 5 , R 6 , R 7 and R 8 may represent different or the same groups in one molecule, and an acid neutralizing agent , and in the vinyl substituted aromatic monomer as solvent. Process according to claim 17, characterized in that the modified PPE or structurally related polymer, obtainable by the process of claims 1-16, is incorporated into polymer blend beads by means of aqueous suspension polymerization.

Inventors: NELISSEN LAURENTIUS NICOLAAS I, TIMMERMANS HENRICUS CORNELIS M, ZIJDERVELD JOHANNES MARIA, NELISSEN, LAURENTIUS NICOLAAS IDA HUBERTUS, TIMMERMANS, HENRICUS CORNELIS MARIA, ZIJDERVELD, JOHANNES MARIA
Applicants: SHELL INT RESEARCH, SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ B.V.
Application year: 1990
Main classification: C08G65
IPC codes: C08F283, C08L71, C08G65