Composition-dependent morphological transition of hierarchically-ordered structures formed by multiblock terpolymers
Composition-dependent morphological transition of hierarchically-ordered structures formed by multiblock terpolymers
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DOI：
10.1021/ma070155s
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发表时间：
2007-05-29
期刊：
影响因子：
5.5
通讯作者：
Matsushita, Yushu
中科院分区：
文献类型：
--
作者：
Masuda, Jun;Takano, Atsushi;Matsushita, Yushu
研究了两种多嵌段三元共聚物的形态转变。一种是PISISISISIP类型的非嵌段三元聚合物，另一种是PISISI类型的六嵌段三元聚合物，其中P， I和S分别表示聚（2-乙烯基吡啶），聚异戊二烯和聚苯乙烯。这些聚合物样品是基于阴离子聚合法制备的。前者的体积分数为0.08、0.21、0.53，后者的体积分数为0.64、0.75、0.87。通过TEM和SAXS对纳米相分离结构进行了观察，证实了随着P组分体积分数的增加，纳米相分离结构由层中球结构转变为层中柱状结构、层中片状结构和同轴柱状结构，最后转变为洋葱状球形结构。结果表明，多嵌段三元共聚物的形态转变遵循常规规律，即随着φ (P)的增大，P组分的畴形随球-柱-片层-基体的变化而变化。
Morphological transition of two types of multiblock terpolymers with composition has been investigated. One is undecablock terpolymers of the PISISISISIP type, while the other is hexablock terpolymers of the PISISI type, where P, I, and S denote poly(2-vinylpyridine), polyisoprene, and polystyrene, respectively. These polymer samples were prepared on the basis of anionic polymerization method. The volume fractions of P, phi(P), of the former are 0.08, 0.21, 0.53, whereas those of the latter are 0.64, 0.75, and 0.87. Nanophase-separated structures were observed by TEM and SAXS, and it was confirmed that their hierarchical morphology transforms from spheres-in-lamellae structure into cylinders-in-lamellae, lamellae-in-lamella, and coaxial cylinderical structures and finally into onionlike spherical structure with increasing volume fraction of the P component. From these results, it has been found that morphological transition of multiblock terpolymers takes place obeying conventional rule, i.e., the domain shape of P component varies as sphere-cylinder-lamella-matrix as phi(P) increases with keeping hierarchical lamellar structure from I and S.