Synthesis Of High Ordered Ladderlike Polysilsesquioxane

ⅠSynthesis and chracterization of high ordered Ladderlike Polysilsesquioxane Since Brown first reported the synthesis of ladderlike polyphenylsilsesquioxane (Ph-T) via "thermal equilibration polymerization"in 1960, it is still a question whether ordered ladderlike polysilsesquioxane can be prepared or not all over the world till now. The synthesis of reactive ladderlike polysiloxane is one of the most challenging tasks, from which a series of novel functional ladderlike polysiloxane can be prepared. Our group has prepared a series of ladderlike polysiloxane via "supramolecular chemistry-dictated step coupling polymerization"since the late 1980s. The initial three chapters of this dissertation aim to improve the regularity of ladderlike polysiloxane through strong H-bonding template and slowly dropping half water for hydrolysis and condensation. (1)Synthesis of well-defined and functional polyhydrosiloxane (H-OLPS) with reaction groups: the peak of -HSiO2/2 with the baseline width of about below 1 ppm in 29Si-NMR spectrum is much narrower than that of the polysilsesquioxane (> 8~10 ppm) prepared by the usual dehydration condensation method, which shows that the regularity of H-OLPS is obviously improved. Pure inorganic ladderlike polyhydrosilsequioxane (H-T) was prepared by the way of subsection hydrolysis. (2) Synthesis of high ordered and soluble CH-T: in 29Si-NMR spectrum, the peak of –SiO3/2 with the baseline width below 3 ppm, and they predict potential application for modification some materials by cyclohexyl-side chains'capability. ⅡThe research of grafting copolymerization by higher valence transition metal Ni(Ⅳ)...