Hexaphenyl cyclotrisilazane was synthesized from diphenyl dichlorosilane and ammonia with toluene as solvent.The effects of input material concentration, reaction temperature, ammonia flow rate and separation method o...Hexaphenyl cyclotrisilazane was synthesized from diphenyl dichlorosilane and ammonia with toluene as solvent.The effects of input material concentration, reaction temperature, ammonia flow rate and separation method on product yield were investigated.The structure of hexaphenyl cyclotrisilazane was characterized with FTIR and XRD.It was found that when diphenyl dichlorosilane concentration was 0.96 mol·L -1 , reaction temperature was 111—112℃,NH3 flow rate was 0.02 m3·h -1 , the yield of hexaphenyl cyclotrisilazane could reach 91.1%.Using ammonia water was better than hot filtration to weed out ammonium chloride at the period of product separation.It enhanced separation efficiency and simplified the process.At the same time it also decreased pollution to the environment by reducing volatile matter of toluene.展开更多
We report a synthetic design and the experimental exploration of preparation of disubstituted polyacetylenes （PAs, P3） through 1,3-dipolar cycloaddition of azides with precursor PA bearing alkyne pendants. The precu...We report a synthetic design and the experimental exploration of preparation of disubstituted polyacetylenes （PAs, P3） through 1,3-dipolar cycloaddition of azides with precursor PA bearing alkyne pendants. The precursor PA （P2） was derived by desilylation of the pristine PA with trimethylethynylsilane side chains （P1）. P1 was obtained by polymerization of a dual-alkyne containing monomer with one of the alkynes end-capping by trimethylsilane （M） under the promotion of WC16-Ph4Sn catalyst. Two synthetic routes, i.e. two-steps （from P1 to P3 via precursor P2） and one-pot （from P1 to P3 without separation and purification of P2） were tried and the results indicated that one-pot strategy is more facile and resultant P3-1 showed higher purity and higher molecular weight than the resultant of P3-2. By using the techniques such as GPC, FTIR and 1H NMR spectroscopy the polymerization behavior and the structures of the polymers were well characterized.展开更多
文摘Hexaphenyl cyclotrisilazane was synthesized from diphenyl dichlorosilane and ammonia with toluene as solvent.The effects of input material concentration, reaction temperature, ammonia flow rate and separation method on product yield were investigated.The structure of hexaphenyl cyclotrisilazane was characterized with FTIR and XRD.It was found that when diphenyl dichlorosilane concentration was 0.96 mol·L -1 , reaction temperature was 111—112℃,NH3 flow rate was 0.02 m3·h -1 , the yield of hexaphenyl cyclotrisilazane could reach 91.1%.Using ammonia water was better than hot filtration to weed out ammonium chloride at the period of product separation.It enhanced separation efficiency and simplified the process.At the same time it also decreased pollution to the environment by reducing volatile matter of toluene.
基金partially supported by the National Natural Science Foundation of China (21074113,20634020 & 20974028)the National Basic Research Program of China (973 Program,2009CB623605)+1 种基金the Research Grants Council of Hong Kong (603509 & HKUST2/CRF/10)the University Grants Committee of Hong Kong (AoE/P-03/08)
文摘We report a synthetic design and the experimental exploration of preparation of disubstituted polyacetylenes （PAs, P3） through 1,3-dipolar cycloaddition of azides with precursor PA bearing alkyne pendants. The precursor PA （P2） was derived by desilylation of the pristine PA with trimethylethynylsilane side chains （P1）. P1 was obtained by polymerization of a dual-alkyne containing monomer with one of the alkynes end-capping by trimethylsilane （M） under the promotion of WC16-Ph4Sn catalyst. Two synthetic routes, i.e. two-steps （from P1 to P3 via precursor P2） and one-pot （from P1 to P3 without separation and purification of P2） were tried and the results indicated that one-pot strategy is more facile and resultant P3-1 showed higher purity and higher molecular weight than the resultant of P3-2. By using the techniques such as GPC, FTIR and 1H NMR spectroscopy the polymerization behavior and the structures of the polymers were well characterized.
