First-order Structure and Solution Properties of Monodisperse Graftcopolymers as Studied by Light Scattering

本研究合成了三种不同结构的接枝共聚物，并研究了它们的溶液性质：（1）具有部分氘代臂的星形聚苯乙烯;（2）具有不同化学结构臂的星形聚苯乙烯;（3）在茎中部附近具有许多接枝链的嵌段接枝共聚物。(1)测量了CS2中内、外标记星的中子小角散射。通过数据分析，我们可以得出以下结论。(A)（B）真实的星形聚合物的结构函数与高斯型星星的结构函数相差甚远，在近中心的短距离处具有较大的链段两两相关性。(2)这被合成用于对应于发行者（1）的光散射测量。首先，我们制备了一种由聚（2-乙烯基萘）和聚（4-乙烯基苯基二甲基乙烯基硅烷）组成的二嵌段共聚物，聚（2-乙烯基萘）是化学上不同的臂，聚（4-乙烯基苯基二甲基乙烯基硅烷）是中心聚合物。然后，活性聚苯乙烯与中心聚合物偶联成为星星的臂。(3)茎聚合物是聚苯乙烯，而接枝聚合物是聚乙二醇。共聚物在选择性溶剂1-甲基环己醇中形成大胶束。在30 - 45 ℃范围内，临界胶束浓度强烈依赖于温度。表观分子量、回转半径、流体动力学半径和散射函数的实验结果表明，胶束的大小和形状可能是不均匀的，在胶束形成的初始阶段是棒状的，在平衡阶段则是空心球形或畸形的。

In this study, the following three types of graftcoplymers were synthesized and their solution properties were investigated: (1) Star-shaped polystyrene having a portionally deuterated arm; (2) Star-shaped polystyrene having a chemically-different arm; (3) Block-graftcopolymer with many grafted chains near the middle part of the stem.(1) Small-angle neutron scattering from the inner- and outer- labeled stars in CS2 were measured. The data analysis has allowed us to make the following conclusions. (A) Inner part of an arm chain in the star-shaped polymer is more expanded by about 2 times than the outer part of the arm. (B) Structure function of real star-shaped polymers is far from that of the Gaussian star, having large segmental pairwise correlation at short distances near the center.(2) This was synthesized for light-scattering measurements corresponding to the issuer (1). First, we made a diblockcopolymer consisting of poly(2-vinlynaphthalene), which would be a chemically-different arm, and poly(4- vinylphenyldimethylvinylsilane), which would be the center polymer. Then, living polystyrenes were coupled with the center polymer to be the arms of star.(3) The stem polymer was polystyrene, while the grafted polymer was polyethylene glycol. The copolymer formed a large micelle in a selective solvent, 1-methylcyclohexanol. The critical micelle concentration depends strongly on the temperature in the range of 30 - 45ﾟC. Experimental results of apparent molecular weight, radius of gyration, hydrodynamic radius, and scattering function suggest that the micelle may be nonuniform in size and shape, being rather rod-shaped in the initial stage of micelle formation and grow up to be hollow spherical or disshaped at the equilibrium.