Polyisocyanate compositions modified by thermal treatment of tolylene-diisocyanate in the presence of organotin compounds.

摘要

1,158,185. Polyisocyanate compositions obtained from tolylenediisocyanates. SUMITOMO CHEMICAL CO. Ltd. 18 Jan., 1967 [19 Jan., 1966], No. 2736/67. Heading C2C. The invention relates to a process for the preparation of polyisocyanate compositions which comprises heating at 150‹ to 250‹ C. in a dry inert atmosphere, e.g. nitrogen, in the presence, as catalyst, of one or more compounds represented by the general formulµ wherein R and R1 are alkyl groups, a tolylenediisocyanate-tarry matter mixture obtained by the phosgenation of a tolylene diamine. The catalyst may be stannous octoate, stannous oleate, stannous acetate, dimethyltin distearate and dilauryltin diacetate and used in an amount of 0À1 to 2% preferably 0À5 to 1% by weight based on the toluylene diisocyanatetarry matter mixture.