The linear viscoelastic properties of block copolymer solutions forming hexagonal close-packed cylindrical domains and their relaxation dynamics were investigated by using a rheo-optical method based on simultaneous measurements of stress and strain-induced birefringence. The sample solution is composed of a PS- b -PI diblock copolymer and a mixed solvent of DOP and SALACOS 913, which are a neutral solvent for both PS and PI and a highly selective solvent for PI, respectively. The copolymer concentration was fixed, and the DOP fraction of the mixed solvent was increased to change the domain structure from a hexagonal close-packed cylindrical structure to a spherical structure. The sign of the complex strain-optical coefficient, which is the complex ratio of the oscillatory strain-induced birefringence to the strain, varied with frequency, indicating that the viscoelastic relaxation spectra include multiple relaxation modes. Four relaxation modes were successfully estimated with the aid of the modified stress-optical rule. The four modes were assigned to (1) reorientation of corona chains, (2) reorientation of core chains, (3) deformation of domains, and (4) reorientation of grains. The intrinsic birefringence of the cylindrical structure was found to be 1.7 × 10 −5 . By assuming entropic stress of grain reorientation, the grain size was estimated to be ~0.2 μm from the viscoelastic intensity. The linear viscoelastic properties of block copolymer solutions forming hexagonal close-packed cylindrical domains were investigated by using a rheo-optical method. Based on the modified stress-optical rule, the complex shear modulus was separated to four relaxation modes. Considering the sign and magnitude of the stress-optical coefficient associated with each mode, the four modes were assigned to (1) reorientation of corona chains, (2) reorientation of core chains, (3) deformation of domains, and (4) reorientation of grains. The results were compared with those for spherical domains.

中文翻译：

---

形成六方密堆积圆柱畴的嵌段共聚物溶液的线性粘弹性和分子动力学的流变光学研究

通过使用基于应力和应变诱导双折射的同时测量的流变光学方法研究了形成六边形密堆积圆柱域的嵌段共聚物溶液的线性粘弹性特性及其弛豫动力学。样品溶液由 PS-b-PI 双嵌段共聚物和 DOP 和 SALACOS 913 的混合溶剂组成，它们分别是 PS 和 PI 的中性溶剂和 PI 的高选择性溶剂。固定共聚物浓度，增加混合溶剂的 DOP 分数，使畴结构从六边形密堆积圆柱结构转变为球形结构。复应变光学系数的符号，即振荡应变引起的双折射与应变的复比，随频率变化，表明粘弹性弛豫谱包括多种弛豫模式。借助改进的应力光学规则成功地估计了四种弛豫模式。这四种模式被指定为 (1) 电晕链的重新定向，(2) 核心链的重新定向，(3) 域的变形，以及 (4) 晶粒的重新定向。发现圆柱形结构的固有双折射为1.7×10 -5 。通过假设晶粒重新取向的熵应力，根据粘弹性强度估计晶粒尺寸为~0.2 μm。通过使用流变光学方法研究了形成六边形密堆积圆柱域的嵌段共聚物溶液的线性粘弹性。基于修正的应力-光学规则，复剪切模量分为四种松弛模式。考虑到与每种模式相关的应力光学系数的符号和大小，四种模式被分配为 (1) 电晕链的重新定向，(2) 核心链的重新定向，(3) 域的变形，以及 (4) 重新定向谷物。将结果与球形域的结果进行比较。