THE SYNTHESIS AND X-RAY-DIFFRACTION STUDY OF THE LADDER-LIKE POLYSILSESQUIOXANES WITH SIDE-CHAIN ESTER GROUPS

The highly regular ladder-like polysilsesquioxanes with different leng th side-chain ester groups were first synthesized via the hydrosilylat ion reaction. Various vinyl-terminated esters (methyl acrylate, butyl acrylate, octyl acrylate and 2-ethyl hexyl acrylate) same linked to th e homopolymeric ladder-like polyhydrosilsesquioxane and copolymethyl-h ydrosilsesquioxane in the presence of dicyclopentadienyl platinum dich loride as catalyst respectively. They are soluble in toluene and tetra hydrofuran and insoluble in hexane, acetone and methanol Their structu res have been characterized by IR spectroscopy, H-1-NMR (nuclear magne tic spectroscopy), Si-29-NMR and X-ray diffraction. X-ray diffraction patterns indicated that the regularity of ladder-like polysilsesquioxa ne with longer side-chain ester is higher than that with shorter side- chain ester. The regularity of the homopolymeric ladder-like polyhydro silsesquioxane with side-chain ester is lower than that of the corresp onding copolymethyl hydrosilsesquioxane. (C) 1997 by John Wiley & Sons , Ltd.