SYNTHESIS AND PROPERTIES OF BIODEGRADABLE COPOLYMERS BASED ON POLYETHER OLIGOMERS AND FATTY DIACIDS

Polyether oligomers (M-n = 200-2000) were respectively esterified by s uccinic anhydride and fatty sebacoyl chloride to synthesize correspond ing intermediate diacids, and experimental results of melt polycondens ations based on these two kinds of intermediates were compared. The re asons for affecting higher molecular weight products to be achieved in polymerization with prepolymers based on succinic anhydride esterific ation were theoretically analyzed. Light scattering measurements showe d that copolyanhydrides with higher molecular weights exceeding 8 x 10 (4) (weight-average) were synthesized from the intermediate diacids pr epared by a new method using fatty diacid chlorides to undergo esterif ication with polyether. Synthesized intermediates were characterized b y H-1-NMR and infrared spectroscopy. Intrinsic viscosity of the polyme rs were measured to display the advancement of polymerization. The pro perties of polymers were investigated by X-ray diffraction and differe ntial scanning calorimetry analysis as well. (C) 1997 John Wiley & Son s, Inc.