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机构地区:[1]大连理工大学化工学院高分子材料系,辽宁大连116012
出 处:《高分子材料科学与工程》2002年第3期49-50,共2页Polymer Materials Science & Engineering
摘 要:用 Na BH4作还原剂对含有二氮杂萘酮结构的聚醚砜酮 (PPESK)进行羟基化改性。用 FT- IR和1H-NMR对还原后的聚醚砜酮 (PPESK- OH)的结构进行表征 ,研究了反应时间、温度、溶剂及反应物浓度对还原反应的影响 ,并讨论了反应动力学。结果表明 ,PPESK在 DMAc中用 Na BH4作还原剂的反应对于羰基的浓度为二级反应 ,反应活化能为 4 4.2 k J/ mol。Poly (ether sulfone ketone) (PPESK) containing the phthalazinone moiety copolymer could be hydroxylated by using a solution of NaBH 4 in DMAc. The resulting PPESK OH was fully characterized by FT IR and 1H NMR. The effects of the reaction time and temperature, the concentration of the polymer and NaBH 4 and the solvent used were studied on the rate of reduction, respectively. The kinetics of the reaction was discussed. The result indicates that the rate of reduction of carbonyl ground increase with the raising of the reaction temperature or the prolonging of the reaction time. The optimum concentration of NaBH 4 is over 10.8 g/L DMAc. The rate constants were measured at three temperatures and the activation energy for the reaction is determined as 44.2 kJ/mol.
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