由凝胶渗透色谱数据及粘度值订定聚乳酸的Mark-Hou wink方程参数

A NEW METHOD FOR DETERMINING MARK-HOUWINK CONSTANTS OF POLYLACTIC ACID FROM GPC-〔η〕 DATA

通过对一组聚乳酸样品的凝胶渗透色谱 (GPC)和特性粘度〔η〕的测定 ,应用直线最小二乘拟合的方法 ,订定了聚乳酸在丙酮中 ,2 5℃下的Mark -Houwink方程参数。结果 :k =1 .672× 1 0 - 4,α =0 .70 3。将这一结果运用到GPC谱图的计算 ,所得的粘度值(〔η〕)与用粘度法实测值比较 ,最大偏差小于 4 93 %

The Mark-Houwink constants of polylactic acid in acetone at 25℃were determined by the least square fitting method using the experimental data of GPC and 〔η〕 for several samples, rather than two samples. The values of k=1.672×10 4 and α=0.703 were obtained and used for GPC calculation. The greatest deviation of 〔η〕 between the experimental data and the calculated data from GPC is less than 4.93%.