建立了用紫外分光光度法测定含甲基丙烯酰氧端基大分子单体数均分子量的新方法 .在本实验条件下 ,以 95%乙醇∶THF( 7∶3 )为溶剂 ,在最大吸收波长 2 1 3nm处对含甲基丙烯酰氧端基的聚四氢呋喃大分子单体进行定量分析 ,所得结果与端基滴定分析法所得结果最大相对误差小于± 5% ,用t检验法对两法测定结果差别进行显著性检验 ,两法所得结果差别无显著意义 .紫外分光光度法可成为一种表征含甲基丙烯酰氧端基大分子单体数均分子量的方便方法 . A new method was established for the determination of the number average molecular weight of the macromonomer containing methacryloyloxy end groups by UV spectrophotometry.Under the conditions of this experiment, 95% ethanol: THF (7: 3) The results showed that the maximum relative error between the obtained results and the end-group titration was less than ± 5% at the wavelength of 231 nm. The t-test was used to compare the two methods The results of the two methods have no significant difference.Ultraviolet spectrophotometry can be a convenient method to characterize the number average molecular weight of the macromonomer containing methacryloyloxy end group.