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机构地区:[1]中国科学院长春应用化学研究所
出 处:《高分子学报》1989年第1期25-31,共7页Acta Polymerica Sinica
摘 要:本文采用GPC-[η]联用的方法研究了一组链立规结构服从Berlloulli分布的聚甲基丙烯酸甲酯的无扰尺寸。对凝胶色谱柱组的扩展效应对无扰尺寸测定的影响进行了讨论。实验结果与Flory等人的Monte Carlo计算结果一致。本文还修正了独立内旋转条件下计算高分子链无扰尺寸的Ptitsyn公式。实验订定了不同规整度的甲基丙烯酸甲酯在30℃、四氢呋喃中的Mark-Houwink方程[η]=KM~α。The unperturbed dimensions for a series of poly (methyl methacrylates) with Bernoullian distribution of stereochemical composition has been studied. A technique involving a gel permeation chromatography coupled with capillary viscometer was used for this purpose. The effect of the column dispersion of the GPC columns on the measurement of unperturbed dimension has been discussed. It has been shown that the experimental results are in good agreement with the values predicted by Monte Carlo calculation.A modified equation has been proposed to calculate the unperturbed dimension of the polymers with asymmetric substitutents and independent internal rotations.The parameters, K and a of [η] = KMa for a series of stereoregular PMMA in tetrahy-drofuran at 30℃ has also been determined.
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