采用我们前期发展的测定多相高聚物中界面相厚度及相区尺寸的NMR新方法对两种不同嵌段结构的聚苯乙烯一聚丁二烯嵌段共聚物进行了研究,并与关于界面相厚度的高分子物理理论结果进行对比.该NMR方法采用偶极滤波一自旋扩散技术分别测定非界面相的柔性区与界面相中质子的百分含量,然后根据界面相与柔性相的几何关系计算界面相厚度.研究结果表明这两种嵌段共聚物具有几乎相同的界面相厚度,该结果与Helfand等人关于多相高聚物中界面相厚度的自洽场理论预言基本符合.
In this paper, we report quantitative determination of interphase thickness and domain size in poly (styrene)-block-poly (butadiene) and poly (styrene)-block-poly (butadine)-block-poly (styrene) copolymers (PS-PB and PS-PB-PS) by novel solid-state NMR methods developed recently in our group. It was found that the block copolymers having equal polystyrene (PS) weight fractions (32.5%) and different block structures have the same interphase thickness (ditp). These experimental results were in agreement with theoretical prediction of the interphase thickness in polymer blends made by Helfand using SCFT theory.