L-乳酸预聚物扩链反应的宏观动力学  

Macro-Kinetics for Chain Extension of L-Lactic Acid Prepolymer

作　　者：陈昀[1] 李园园[1] 

机构地区：[1]北京服装学院材料科学与工程学院,北京100029

出　　处：《石油化工》2010年第8期902-908,共7页Petrochemical Technology

基　　金：北京市教育委员会科技发展计划面上项目(KM20071002006)

摘　　要：分别用六亚甲基二异氰酸酯(HDI)和二苯基甲烷二异氰酸酯(MDI)为扩链剂,在150℃、氮气气氛下进行了L-乳酸预聚物熔融扩链反应动力学实验,测定了不同反应时间时试样的数均相对分子质量,建立了L-乳酸预聚物扩链反应的宏观动力学模型(模型Ⅰ)和考虑时间因素的宏观动力学模型(模型Ⅱ)。将实验数据用最小二乘法回归得到宏观动力学模型参数,采用积分法对模型进行了检验及辨识。实验结果表明,模型Ⅱ与两种扩链剂的扩链反应的实验数据均吻合,其中,时间因子均为0.5;与MDI相比,HDI作为L-乳酸预聚物扩链剂的扩链效果更好。Chain extension reaction of L-lactic acid prepolymer in a melting state at 150 ℃ under nitrogen atmosphere was investigated with hexamethylene diisocyanate （liD/） or 4, 4＇-diphenylmethane diisocyanate （MDI） as chain extender. Number-average relative molecular masses of the chain extended products were determined. Macro-kinetic model Ⅰ ＆ Ⅱ for the L-lactic acid prepolymer chain extension reaction were established. The reaction kinetic parameters were obtained by means of least square method and the reaction kinetic models were confirmed by means of integral method. Results of simulation calculation showed that macro-kinetic model Ⅱ with time exponent fitted well the experimental data from the chain extension reaction with HDI or MDI and both the time exponents were 0.5. The results also indicated chain extender HDI was more effective than MDI.

关 键 词：聚L-乳酸 熔融扩链 宏观动力学 六亚甲基二异氰酸酯 二苯基甲烷二异氰酸酯 

分 类 号：TQ323.9[化学工程—合成树脂塑料工业]