| abstract |
PURPOSE: To prepare a propylene-butadiene copolymer useful for tires, etc. and having high frictional coefficient, by mixing one of the catalytic component containing a trialkylaluminum compound with the other component containing a pentavalent vanadium compound and an alkoxy-containing compound, in the presence of monomers. n CONSTITUTION: (A) A system containing a trialkylaluminum compound (e.g. triisobutylaluminum, etc.) is mixed with (B) another system containing (a) a pentavalent vanadium compound (vanadyl trichloride, etc.) and (b) an alkoxy- containing compound [e.g. aluminum tri(3-methyl-1-isobutyl-butoxide), etc.] in the presence of a liquefied propylene-butadiene mixture, and the bulk copolymerization of propylene and butadiene is carried out to give the desired copolymer. Preferably the amount of the monomers added in the preparation of the catalyst is 1/50W 1/2 of the whole amount, and the molar ratio of (A)/(a) is 2W50. n COPYRIGHT: (C)1980,JPO&Japio |