马来酸酐扩链端羟基聚丁二烯表征

Characterization of Chain-Extending Hydroxy-terminated Polybutadiene by Maleic Anhydride

用马来酸酐在常温条件下对端羟基聚丁二烯进行扩链,通过黏度法测定了扩链前后端羟基聚丁二烯的相对平均分子质量,并用傅立叶变换红外光谱、核磁共振谱对扩链前后端羟基聚丁二烯的结构进行了表征。结果表明,扩链后相对平均分子质量增大至原来相对平均分子质量的1.46倍,在傅立叶变换红外光谱图上显示出较强的酯基伸缩振动吸收峰(1735cm-1),同时也用核磁共振谱排除了乙醇的酯化,这说明端羟基聚丁二烯的扩链不是简单的端羟基转变为端羧基,而是酯化反应。

Hydroxy - terminated Polybutediene is chain- extended hy meleic anhydride st the mild reason condition. The molecular weight of polymers before and aider the reaction can be calculated from the test data of intrinsic viscosities for the dilute solution,and the structure of HTPB before and after is characterized by IR and HNMR. The result shows that the molecular werght of the reaction product of maleic enhydride and HTPB is 1.46 times of the molecular weight of HTPB. It indicates the reality of the chain extension reaction. The IR and HNMR spectrum of maleic anhydride drain- extended HTPB end HTPB reveal that the reaction is esterification of HTPB, beside the transformation of hydroxy group - terminated to carboxyl goup- terminated.