The Synthesis of Silicon-containing Polyester Directly from SiO_2 and Characterization of Its Structure

摘要

A new approach to the synthesis of a novel silicon-containing polyester by non-carbothermal method directly from SiO_2 was studied. At first, a high reactive pentacoordinate organic silicon compound (KSi(OCH_2CH_2O)_2(OCH_2CH_2OH)) was prepared by the reaction of the fumed silica with ethylene glycol (EG) and KOH. Then, a novel double hydroxy tetracoordinate silicon monomer (OCH_2CH_2O)Si(OCH_2CH_2OH)(OCH_2CH_2OCH_2CH_2OH) was synthesized by the reaction of ClCH_2CH_2OH with reactive pentacoordinate silicon compound. Finally, a silicon-containing polyester was synthesized by low temperature solution condensation between tetracoordinate silicon compound and p-phthaloyl chloride in dimethyl sulfoxide (DMSO). The product was characterized by FTIR, TG, GPC, etc. The IR spectra of polyester exhibited a characteristic strong absorption band for ester carbonyl in the 1722.2cm~(-1). IR spectra also showed absorption at 1124.6cm~(-1) due to the O-Si-O group. TG analysis showed its good thermal stability. GPC analysis showed that the number average molecular weight of this silicon-containing polyester was about ninety thousand.