| In this thesis, a new synthetic route to prepare polymer networks is described . BA is copolymerized with p-t-butyl-phenol blocked dimethyl-m-isopropenyl-benzyl isocyanate, which can be deblocked via pyrolysis. On heating, the copolymer can be converted to a polymer with pending isocyanate groups, which react with 6-methyl methylisocytosine. A polyacrylate network is expected to form via hytrogen-bonded self-assembly ureido-pyrimidone dimmer. The following researches were carried out.Firstly, p-t-butyl-phenol blocked dimethyl-m-isopropenyl-benzyl isocyanate (BTMI) was synthesized and copolymerized with n-butyl acrylate (BA). The monomer reactivity ratios, rBTMI=0.13, rBA=0.22, were obtained at 60℃by Kelen-Tudos method, and the co-isotactic parameter of BTMI with BA, σ=0.33, was obtained. The results show the reactivity of BTMI is less than one of BA.Secondly, blocked isocyanate polymer was synthesized by the emulsion polymerization of BTMI and BA.The effect of reaction time ,monomer ratio, emulifier SDS quantity on conversion and molecular weight were investigated. Thirdly, the kinetics of pyrolysis of the copolymer of p-t-butyl-phenol blocked dimethyl-m-isopropenyl-benzyl isocyanate and butyl acrylate was studied by in-situ quantitive FTIR and temperature programmed in the ground of pure N2 . The -N=C=O absorption at 2270cm-1 was monitored with the an absorption peak for the N-H group reducing. A number of spectra were recorded over a wide temperature range. It shows the beginning temperature of the decomposition is 160℃ and isocyanates deblocked are self-oligmerized above 280℃. The activiation energy is 98.433kJ/mol and the reaction order is 1 for the first stage ; the exponential factor (γ) is 2.987×107s-1 . Finally, the self-assembly sepermolecular network was formatted by in-situ self-combination with methylisocytosine, after the copolymer of p-t-butyl-phenol blocked dimethyl-m-isopropenyl-benzyl isocyanate and butyl acrylate was degraded in solvent dimethyl sulfoxide at 170℃.
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