CARBODIIMIDES

摘要

1476088 Carbodiimides IMPERIAL CHEMICAL INDUSTRIES Ltd 16 March 1976 [3 April 1975 (4) 16 April 1975 30 Oct 1975] 13656/75 13657/75 13658/75 13659/75 15649/75 and 44965/75 Headings C2C and C2P Isocyanate groups in a refined organic isocyanate are converted to carbodiimide groups by heating the isocyanate with a catalyst of the formula or the 2,3- or 3,4-mono-unsaturated analogues thereof, wherein R is an optionally substituted hydrocarbyl group, R1 to R8 are hydrogen, chlorine or C 1 to C 4 alkyl, and X and Y are chlorine or bromine or X and Y taken together are =O, =S, or =N-aryl, and deactivating the catalyst by adsorption on a substrate with subsequent removal of the substrate or by addition of one or more of the halides of hydrogen, phosphorus or tin or an oxyhalide of phosphorus or tin. A proportion of the carbodiimide groups may react on standing with further of the isocyanate groups to form uretonime groups. The catalyst of the formula may be prepared by reacting phenyldichlorophosphine with butadiene, the corresponding oxide and sulphide may be made by from this chloride by hydrolysis or reaction with sodium sulphide, the phospholenes may be obtained by dehalogenation with magnesium and phosphinimines may be prepared by reaction of phosphines with the appropriate azide. The catalyst of the formula may be prepared by reacting the grignard reagent ClMg(CH 2 ) 4 MgCl with phenyldichlorophosphine to form and reacting this with chlorine. The isocyanates containing carbodiimide groups and optionally uretonimine groups produced by the present process may be used to produce polyurethanes.