SYNTHESIS AND PROPERTIES OF BLOCK COPOLYMERS BASED ON AMINE-TERMINATED POLYDIMETHYLSILOXANE AND AROMATIC POLYAMIDES

Polysiloxane-aramid block copolymers were synthesized by a one-pot two-step method of direct polycondensation using triphenyl phosphite and pyridine as the condensing agent. Carboxyl-terminated aramid oligomers were prepared by the reaction of 3,4 prime -oxydianiline and isophthalic acid, and then condensed with bis(3-aminopropyl)polydimethylsiloxane giving the block copolymers with inherent viscosities of 0. 21-0. 41 dl g** minus **1. They are soluble in amide-type solvents like N,N-dimethylacetamide and gave translucent and ductile films by casting from the solutions. These block copolymers start to decompose around 300 degree C.