| abstract |
PURPOSE: To obtain a moisture-curable film forming agent polyisobutylene having a high breaking ability and moisture-curability, by reacting a specific isobutylene oligomer with an organosilicon compound in the absence of atmospheric moisture in the presence of a hydrosilation catalyst. n CONSTITUTION: An isobutylene oligomer having groups of formula I (wherein, R" is H, methyl) at the two terminal positions and average molecular weight of 1000 to 100,000, is react, with a stoichiometric amount of an organosilicon compound of formula II [wherein, substituent R is a monovalent hydrocarbon (halide); R' is a 2-10C alkylene; X is a hydrolyzable atomic group attached to Si through N or O; (n) is 1-5] in the absence of atmospheric moisture in the presence of a hydrosilation catalyst comprising platinum group metal (compound) (e.g. a complex of a hexachloroplatinic acid and a vinyl group-containing organosiloxane) in a liquid hydrocarbon diluent at a temp. from 50 to 150°C, to obtain moisture-curable polyisobutylene containing an isobutylene oligomer in which the terminal unit contains an organosiloxy group of formula III and 95% or more of the non-terminal units is the group of formula IV, and any other remaining reactive units other than the residue of the initiator-chain transfer agent used to polymerize the isobutylene are derived from ethylene unsaturated hydrocarbons that are polymerizable with isobutylene. n COPYRIGHT: (C)1989,JPO |