Spatial distribution of lamella structure in PCL/PVB band spherulite investigated with microbeam small- and wide-angle X-ray scattering
Spatial distribution of lamella structure in PCL/PVB band spherulite investigated with microbeam small- and wide-angle X-ray scattering
复制标题
DOI：
10.1016/s0032-3861(03)00591-3
复制
发表时间：
2003-09-01
期刊：
影响因子：
4.6
通讯作者：
Amemiya, Y
中科院分区：
文献类型：
--
作者：
Nozue, Y;Kurita, R;Amemiya, Y
微束小角和广角X射线散射（SAXS/WAXS）技术提供了有关聚合物晶体微米级结构不均匀性的新信息。通过使用该技术，我们研究了可混溶聚合物共混物聚（F：己内酯）（PCL）/聚（乙烯醇缩丁醛）（PVB）带球晶内片层的结构不均匀性以及结晶过程中片层的结构发展。据了解，由于成核频率较低，PCL/PVB形成非常大的球晶（半径大约为几毫米），具有高度规则的能带结构，并且在41℃结晶的PCL/PVB具有至少两种片层结构（150埃、180埃）。将X射线微束最初固定在带状球晶生长前沿附近的外部，我们观察了局部点的片晶形成，并发现较大的长周期在较短的长周期出现之前生长。我们还通过X射线微束沿其径向扫描带状球晶的SAXS实验观察到，具有较大长周期的片晶的取向与具有较短长周期的片晶的取向不同。此外，通过扫描微束 WAXS 观察到薄片扭曲的不连续性。根据实验结果，我们提出了两种可能的空间分布模型。还讨论了PCL/PVB在35℃下结晶的结果。 (C) 2003 Elsevier Ltd. 保留所有权利。
The microbeam small- and wide-angle X-ray scattering (SAXS/WAXS) technique gives the novel information about micron-scale structural inhomogeneity of polymer crystal. By using this technique, we have studied structural inhomogeneity of lamella within the band spherulite of miscible polymer blend poly(F: caprolactone) (PCL)/poly(vinyl butyral) (PVB) and the structure development of lamella during crystallization. It is known that PCL/PVB forms very large spherulites (similar to several mm, in radius) with highly regular band structure because of low frequency of nucleation and that PCL/PVB crystallized at 41 degreesC has at least two kinds of lamella structure (150 Angstrom, 180 Angstrom). With an X-ray microbeam initially fixed outside near the growth front of the band spherulite, we have observed the lamella formation at the local point and have found that the larger long period grows before the appearance of the shorter long period. We have also observed that the orientation of lamella with the larger long period is different from that of lamella with the shorter long period from SAXS experiment with an X-ray microbeam scanning the band spherulite along its radial direction. Further, the discontinuity in lamella twisting was observed from scanning microbeam WAXS. Based on the experimental results, we propose two possible spatial distribution models. The result of PCL/PVB crystallized at 35 degreesC was also discussed. (C) 2003 Elsevier Ltd. All rights reserved.