Tunable Photonic Crystals: Control of the Domain Spacings in Lamellar-Forming Diblock Copolymers by Swelling with Immiscible Selective Solvents and a Neutral Solvent
Tunable Photonic Crystals: Control of the Domain Spacings in Lamellar-Forming Diblock Copolymers by Swelling with Immiscible Selective Solvents and a Neutral Solvent
复制标题
DOI：
10.1021/ma501560n
复制
发表时间：
2014-10
期刊：
影响因子：
5.5
通讯作者：
Akifumi Matsushita;S. Okamoto
中科院分区：
文献类型：
--
作者：
Akifumi Matsushita;S. Okamoto
用小角X射线散射(SAXS)和紫外-可见光谱(UV-Vis)研究了三种不同相对分子质量的聚苯乙烯-嵌段聚异戊二烯(PS-b-PI)在混合溶剂中溶胀的相分离形态。混合溶剂包括邻苯二甲酸二甲酯(DMP)和正十四烷(C14)，PS和PI的选择性溶剂，以及中性溶剂邻苯二甲酸二辛酯(DOP)。DMP和C14是不相容的，因此选择性地隔离在相应的相中。SAXS测量证实，在大多数情况下观察到了片层的形态，并且结构域间距取决于聚合物的摩尔质量、溶液中的浓度和混合溶剂的组成。DMP和C14的加入增加了PS和PI相间的相容性，而中性溶剂DOP的加入则降低了PS和PI相间的相容性。结构域间距以这种方式在很大范围内变化。结果表明，相对分子质量最大的两嵌段共聚物PS-b-PI在3个波长处有反射峰.
The phase-separated morphology of three different molecular weights of polystyrene-block-polyisoprene (PS-b-PI) swollen with mixed solvents was studied by small-angle X-ray scattering (SAXS) and UV–vis spectroscopy. The solvent mixtures consisted of dimethyl phthalate (DMP) and n-tetradecane (C14), selective solvents for PS and PI, respectively, and a neutral solvent, di-n-octyl phthalate (DOP). DMP and C14 are immiscible and hence selectively sequestered in the corresponding phases. SAXS measurements confirmed that a lamellar morphology was observed in most cases and that the domain spacing depended on the polymer molar mass, the concentration in solution, and the composition of the mixed solvent. The incompatibility of the PS and PI phases was increased by addition of DMP and C14 and decreased by addition of the neutral solvent DOP. The domain spacing was varied in this manner over a wide range. The diblock copolymer PS-b-PI with the largest molecular weight showed reflection peaks at wavelengths from 3...