SPIROPOLYMER HAVING CYCLOTRIPHOSPHAZENE RING AND ITS PREPARATION

摘要

PURPOSE:To produce the titled spiropolymer superior in thermal resistance and flame retardance and suitable as flame retardant for fibers, etc., by polycondensing a specified tetrahalogenocyclotriphosphazene derivative and a tetrahydroxy compound. CONSTITUTION:A 1, 1-bis ( substituted amino ) -3,3,5,5-tetrahalogenocyclotriphosphazene of formula I (where R1 is aryl; X is a halogen) and a tetrahydroxy compound of formula II (where R2 is a quadrivalent aliphatic or aromatic group) (e.g., pentaerythritol, 1,2,4,5-tetrahydroxybenzene) are polycondensed according to the conventional polycondensation procedures, such as solution polymerization, solid phase polymerization or the like means, thereby producing a solvent-soluble spiropolymer having cyclotriphosphazene rings of noncombustible groups consisting of recurring units of formula III and yet not containing any P-Cl bond susceptible to hydrolysis.