Liu Dongmei, Lin Ye, Gong Kai, Bo Huifeng, Li Deyang, Zhang Zhanxin, Chen Wenduo
School of Science, North China University of Science and Technology Tangshan 063210 P. R. China
School of Materials, Sun Yat-sen University Guangzhou 510275 P. R. China
RSC Adv. 2021 Nov 29;11(61):38316-38324. doi: 10.1039/d1ra07671j.
The phase behavior and interfacial tension of ternary polymeric mixtures (polystyrene/polystyrene--poly(methyl methacrylate)/poly(methyl methacrylate), PS/PS--PMMA/PMMA) are investigated by dissipative particle dynamics (DPD) simulations. Our simulation results show that, as the PS--PMMA diblock copolymer concentration increases, the interfacial tension decreases due to the decayed correlations between homopolymers PS and PMMA. When the chain lengths of copolymers are fixed, with the increase of the chain lengths of PS and PMMA homopolymers the interfacial width becomes wider and the interfacial tension becomes smaller, due to the copolymers presenting more stretched and swollen structures in the mixtures with the short length of homopolymers. However, with simultaneously increasing chain lengths of both diblock copolymer and homopolymers with a fixed ratio, the interfacial tension increases because the copolymer chains with longer chain length penetrate more deeply into the homopolymer phase and the interactions between diblock copolymers become weaker. These results will provide a way to mix incompatible homopolymers to improve material performances.
通过耗散粒子动力学（DPD）模拟研究了三元聚合物混合物（聚苯乙烯/聚苯乙烯-聚（甲基丙烯酸甲酯）/聚（甲基丙烯酸甲酯），PS/PS-PMMA/PMMA）的相行为和界面张力。我们的模拟结果表明，随着PS-PMMA二嵌段共聚物浓度的增加，由于均聚物PS和PMMA之间相关性的衰减，界面张力降低。当共聚物的链长固定时，随着PS和PMMA均聚物链长的增加，界面宽度变宽且界面张力变小，这是因为在均聚物链长较短的混合物中，共聚物呈现出更多拉伸和膨胀的结构。然而，当二嵌段共聚物和均聚物的链长以固定比例同时增加时，界面张力会增加，因为链长较长的共聚物链更深入地渗透到均聚物相中，且二嵌段共聚物之间的相互作用变弱。这些结果将为混合不相容的均聚物以改善材料性能提供一种方法。
