【摘 要】
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Novel phosphazene cyclomatrix network polymers were synthesized via the nucleophilic displacement of activated nitro groups of tri(4-nitrophenoxy)tri(phenoxy)cy
【机 构】
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The Key Laboratory of Science and Technology of Controllable Chemical Reactions,Beijing University o
论文部分内容阅读
Novel phosphazene cyclomatrix network polymers were synthesized via the nucleophilic displacement of activated nitro groups of tri(4-nitrophenoxy)tri(phenoxy)cyclotriphosphazene and hexa(p-nitrophenoxy)cyclotriphosphazene with hydroxyls of bisphenol A.Both monomers and polymers were characterized by Fourier transform infrared spectroscopy,1H nuclear magnetic resonance,and elemental analysis measurements,and their structures were identified.Thermal properties of polymers were investigated using dynamic thermogravimetric analysis in air.The results demonstrated that both cyclomatrix phosphazene polymers 4 and 6 were of excellent thermal stability,and their char yields in air at 800℃ were 45.1 and 43.2%,respectively.According to combustion phenomenon,polymer 4 was supposed to be processed with a good flameretardant property because of its excellent crosslinked structure during pyrolysis or combustion.However,polymer 6 yielded the opposite result.
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