The synthesis and X-ray diffraction study of the ladder-like polysilsesquioxanes with side-chain ester groups
β Scribed by Liaoyun Zhang; Daorong Dai; Rongben Zhang
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 297 KB
- Volume
- 8
- Category
- Article
- ISSN
- 1042-7147
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β¦ Synopsis
The highly regular ladder-like polysilsesquioxanes with different length side-chain ester groups were first synthesized via the hydrosilylation reaction. Various vinyl-terminated esters (methyl acrylate, butyl acrylate, octyl acrylate and 2-ethyl hexyl acrylate) were linked to the homopolymeric ladder-like polyhydrosilsesquioxane and copolymethyl-hydrosilsesquioxane in the presence of dicyclopentadienyl platinum dichloride as catalyst respectively. They are soluble in toluene and tetrahydrofuran and insoluble in hexane, acetone and methanol Their structures have been characterized by IR spectroscopy, 1 H-NMR (nuclear magnetic spectroscopy), 29 Si-NMR and X-ray diffraction. X-ray diffraction patterns indicated that the regularity of ladder-like polysilsesquioxane with longer side-chain ester is higher than that with shorter side-chain ester. The regularity of the homopolymeric ladder-like polyhydrosilsesquioxane with side-chain ester is lower than that of the corresponding copolymethyl hydrosilsesquioxane.
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