借宽分散标样数均分子量拟合凝胶渗透色谱校准曲线

The Calibration Curve Fit of Gel Permeation Chromatography by Using Broad Distribution Standards with Known Number-Average Molecular Weight

采用以蒸汽压渗透法(VPO)确定了数均分子量(M_n)_j的宽分散标样,将其GPC谱图划分为若干等分片,依据InM_(ij)=A-BT_(ij)及((?)_n)_j=1/sum (N_(ij)M_(ij)^(-1))二模型,以最小二乘法通过迭代求出最佳A,B值来拟合凝胶渗透色谱校准曲线。实际应用于聚碳硅烷(PCS)样品获得令人满意的结果。误差分析表明:用计算所得校准曲线测定分子量的最大相对误差为0.7％,实际测得的分子量的误差为-0.10％～0.10％,显示了本法省时、准确、适应性广等特点。

Using the broad distribution standards whose number-average molecular weights are determined by Vapor Pressure Osmometer (VPO) and cutting the GpC pliotogram into slices,the calibration carve of GPC was fitted by linear and nonlinear least square methods according to the two modelsThe results of the practical application to the poly-carbosilane are satisfactory.The error analysis showed that the maximum theoretical error of the molecular weight caused by the calculated calibration was 0.7^.In fact,the practical error in the experiment was Only in the range of-0.1^ to Q.1%.The procedure is rapid,accurate and widely applicable.