A method for the preparation of resins based on alpha - methyllstyrol, styrene and isobutene

摘要

1457356 Styrene/α-methylstyrene/isobutene polymers optionally containing saturated phenols HOECHST AG 22 May 1974 [8 June 1973] 22885/74 Heading C3P A process for the manufacture of a hard resin comprises cationically polymerizing a mixture consisting of 10-50% by weight of α-methylstyrene, 40-85% by weight of styrene and 5-50% by weight of isobutene which may contain up to 20% by weight (based on the olefinically unsaturated monomers) of a phenol or mixture of phenols in 20-150% by weight (based on the olefinically unsaturated monomers) of an inert organic solvent, in the presence of 0À1-1À0% by weight (based on the olefinically unsaturated monomers) of a Friedel- Crafts catalyst and, optionally, from 0À1-40% by weight (relative to the olefinically unsaturated monomers) of an ester of an organic carboxylic acid having 2-10 carbon atoms, at a temperature of - 20‹ to 120‹ C. If phenol is absent, the polymers consist of 10-50% by weight of α-methylstyrene, 40-85% by weight of styrene and 5-50% by weight of isobutene with softening points of 50-120‹ C., a relative viscosity (as a 30% solution in toluene at 25‹ C.) of 2À5-4À0 and a density of 1À01-1À07 g./c.c. The products, obtained when a phenol is present, consist of 8-42% by weight of α-methylstyrene units, 33-71% by weight of styrene units, 4-42% by weight of isobutene units and up to 16À5% by weight of the phenol and have a softening point (ring and ball test according to DIN 1995) of 50-120‹ C., a relative density of 1À03-1À06 (at 20‹ C.), a refractive index of 1À58-1À60 (at 20‹ C.) and a relative viscosity of 2À00-4À00 (as a 30% by weight solution in toluene at 25‹ C.). Examples (1)-(7) describe the polymerization of α-methylstyrene, styrene and isobutene with a BF 3 .CH 3 CO 2 C 2 H 5 catalyst in (1)-(4) toluene; (5) diisobutylene; (6) 1,2- dichloropropane; (7)-(8) toluene with ethyl acetate as the moderator and Examples (8)- (13) describe the polymerization of α-methylstyrene, styrene and isobutene in toluene with a BF 3 .CH 3 CO 2 C 2 H 5 catalyst and (9)-(12) phenol; (13)-(14) a mixture of phenol, the cresols and the xylenols. The resins are compounded with benzine, paraffin, ethylene/vinyl acetate copolymers and Micro-wax.