Studies On Preparation Of Poly(Silyl Ester)s By The Reaction Of Diacetoxylsilane And Dicarboxylic Acid

Polymers composed of nucleophilically-labile silyl ester bonds in the main chain are being investigated as a new class of degradable polymers.In initial studies, bis(trimethylsily1)adipate underwent a transsilylation reaction with dichlorotetrasubstituted disiloxanes to give a series of poly(silyl ester)s by Stephen P.Gitto and Karen L.Wooley in 1995. They synthesized a series of polymers.and they studied characterization of the poly(silyl ester)s included infrared spectroscopy, ¹HNMR, and ²⁹SiNMR spectroscopies,etc. But it isn't report that the poly(silyl ester)s were synthesized with acyloxysilane and dicarboxylic acid.This paper reports the synthesis of a series of poly (silyl ester)s by diacetoxylsilane with several dicarboxylic acid.The reaction conditions of every part (temperature, pressure and catalyst) were researched.And the chemical structure and properties of these polymers were confirmed and researched. This paper has four parts as following:1. The synthesis of poly(silyl ester)s by diacetoxylsilane underwent meltcondensation with dicarboxylic acid.A gluey composition was prepared by the polymerization involving triacetoxylmethylsilane and adipic acid. We got two viscosity polymers by the reaction diacetoxydimethylsilane and adipic acid and glutaric acid .and a crystal polymers was prepared by the reaction of diacetoxydimethylsilane with oxalic acid .we found we had got poly(silyl esters)by ¹HNMR as expected.. There are several benefits to this transsilylation approach: no base nor catalyst is required; acetic acid,byproduct is volatile when reaction temperature is higher than its boiling point...