GB1314232A - Hydrocarbon copolymers - Google Patents

Abstract

1314232 Stabilizing polymers E I DU PONT DE NEMOURS & CO 17 June 1970 [24 June 1969] 29439/70 Heading C3P Normally solid α-monoolefin hydrocarbon polymers containing 2 to 50 weight per cent of norbornylene groups wherein R 7 is hydrogen, alkyl, aryl, alkenyl or alkylidene, R 8 is hydrogen or alkyl, or R 7 and R 8 are joined to form an alkenylene group, are stabilized against gelation during shearing phases of bulk processing by mixing therewith (a) a thiuram disulphide wherein R 1 , R 2 , R 3 and R 4 are C 1-18 alkyl, C 6-18 aryl or saturated derivatives thereof, alkaryl or aralkyl, or R 1 and R 2 and/or R 3 and R 4 together form 1,4- or 1,5-alkylene or 3-oxa- 1,5-pentalene; or (b) a xanthogen derivative where R 5 and R 6 are C 1-18 alkyl, C 6-18 aryl or saturated derivatives thereof, alkaryl or aralkyl; in amount of 8 to 100 mole per cent per mole of norbornylene moiety in the copolymer. The copolymers may be derived from C 2-18 α-monoolefins and optionally C 6-22 open chain non- conjugated dienes, and may be prepared by solution or slurry polymerization in the presence of a vanadium or titanium compound/organoaluminium compound catalyst, the stabilizer preferably being added before isolation of the copolymer. Many suitable comonomers and stabilizers are listed and examples describe the stabilizing of (1) ethylene/norbornene-2/1,4- hexadiene copolymer with diethyl xanthogen, ethylene / 5 - methylnorbornene - 2 copolymers with (2) tetramethyl thiuram disulphide and (3) diethyl xanthogen, and (4) ethylene/propylene / norbornene / 1,4 - hexadiene copolymer with diethyl xanthogen.