Patent GB-1311340-A (GB)
Title: Process for producing aromatic graft polymers
IPC: C08F255/06
Filed: 1970-09-30
Abstract: 1311340 Aromatic vinyl graft polymers MITSUI TOATSU CHEMICALS Inc 30 Sept 1970 [4 Oct 1969] 46551/70 Headings C3G and C3P Aromatic vinyl graft polymers are prepared by dissolving 1 to 20 parts by weight of (A) an ethylene/propylene/non - conjugated diene terpolymer rubber and 5 to 50 weight per cent of (A) of (B) a polymer of formula where X is hydrogen, -CH 2 CH 2 OH or -COOH and n is 10 to 100, in 200 parts by weight of (C) a solvent comprising an aromatic vinyl monomer or mixture thereof with an aliphatic vinyl monomer which mixture contains at least 50 weight per cent of said aromatic vinyl monomer, prepolymerizing the resulting solution by bulkpolymerization under agitation sufficient to disperse the terpolymer rubber as a microgel of particle size 0À05 to 15 microns, and completing the polymerization by bulk- or suspensionpolymerization. The aromatic vinyl compound may be styrene, α-methylstyrene, o-chlorostyrene or p-chlorostyrene. The aliphatic vinyl compound may be acrylonitrile, methacrylonitrile, methyl acrylate, butyl acrylate or methyl methacrylate. The rubber may be derived from a straight chain or branched alkadiene, dicyclopentadiene, alkylene or alkylidene norbornenes, and unsaturated derivatives of bicyclo[3.2.1]octane or bicyclo[3.3.1]nonane. The polymers (B) may be prepared by polymerizing butadiene in the presence of a Lewis base, e.g. tetrahydrofuran, an alkali metal, e.g. lithium or sodium, and an aromatic hydrocarbon activator, e.g. naphthalene or 1,2- diphenyl benzene, and terminating the reaction with water, methanol, acetic acid, ethylene oxide or carbon dioxide. The prepolymerization may be effected by heat or in the presence of peroxide catalysts, optionally in the presence of chain transfer agents, e.g. dodecyl mercaptan, antioxidants, e.g. trisnonylphenyl phosphite and 2,6-di-t-butylhydroxytoluene, and plasticizers, e.g. mineral oil and butyl stearate. The polymerization is preferably completed in the presence of a peroxide catalyst in aqueous suspension with calcium phosphate, magnesium phosphate, polyvinyl alcohol or methyl cellulose as suspending agent. The resulting polymers may be made into weather-resistant mouldings. Examples describe the prepolymerization of (1) styrene containing ethylene/propylene/hexadiene - 1,4 rubber, 1,2 - polybutadiene, dibutyl hydroxy toluene and mineral oil with 2,5 - dimethyl - 2,5 - di(t - butylperoxy)hexane followed by suspension polymerization in the presence of t-butylperbenzoate and polyvinyl alcohol; (2) styrene/methyl methacrylate containing ethylene / propylene / ethylidene norbornene rubber, hydroxyethyl terminated 1,2- polybutadiene, butyl stearate, trinonylphenylphosphite and t-dodecyl mercaptan in the presence of dicumyl peroxide followed by suspension polymerization in the presence of tbutyl perbenzoate and polyvinyl alcohol; (3) styrene containing rubbers derived from ethylene, propylene and hexadiene-1,4, dicyclopentadiene or ethylidene norbornene, and 1,2- polybutadiene in the presence of t-butyl cumyl peroxide followed by suspension polymerization in the presence of t-butyl peracetate and polyvinyl alcohol; and (4) styrene/methyl methacrylate/acrylonitrile containing ethylene/propylene/methylene norbornene rubber and carboxyl terminated 1,2-polybutadiene in the presence of di-t-butyl peroxide followed by suspension polymerization in the presence of polyvinyl alcohol.