Synthesis and characterization of a novel terephthalate-bridged ladderlikepolymethylsiloxane

A novel soluble terephthalate-bridged ladderlike polymethylsiloxane was syn thesized successfully by stepwise coupling polymerization in three steps, i ncluding hydrosilylation coupling, hydrolysis and polycondensation. The bis (3-methyldichlorosilylpropyl) terephthalate monomer was first synthesized b y hydrosilylation reaction in the presence of dicyclopentadienylplatinum (I I) chloride (Cp2PtCl2) catalyst. The structures of the monomer and the poly mer were characterized by FTIR, H-1 NMR, C-13 NMR and Si-29 NMR spectroscop y, mass spectrometry, X-ray diffraction, differential scanning calorimetry, vapour pressure osmometry and gel permeation chromatography. Characterizat ion data indicate that the synthesized polymer possesses an ordered ladderl ike structure. (C) 2000 Society of Chemical Industry.