Abstract The location of SiO2 nanoparticles (NPs) grafted with poly(methyl methacrylate) (PMMA) brushes in a phase-separated PMMA/styrene-acrylonitrile (SAN) copolymer (60/40) blend is investigated. The NPs with brushes being much larger than the matrix PMMA chains are located in the PMMA-rich phase. Otherwise, they are easily distributed at the interfacial region between the PMMA- and SAN-rich domains, which is confirmed to be driven by the entropy-dominated interfacial energy between PMMA matrix and brush chains. Based on the semi-quantitative estimation of the interfacial energy, a diagram of state is established to precisely predict the location of NPs in the phase-separated blend matrix with respect to grafting parameters and the molecular weight of chemically similar matrix polymer, which is also applicable to data in other literatures. It can provide a simple and universal strategy to regulate the selective distribution of NPs in a wide range of nanocomposites.

中文翻译：

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二元聚合物共混物中均聚物-刷接枝纳米颗粒的选择性位置控制

摘要 研究了用聚甲基丙烯酸甲酯 (PMMA) 刷接枝的 SiO2 纳米粒子 (NPs) 在相分离的 PMMA/苯乙烯-丙烯腈 (SAN) 共聚物 (60/40) 共混物中的位置。具有比基体 PMMA 链大得多的刷子的 NP 位于富含 PMMA 的相中。否则，它们很容易分布在富含 PMMA 和 SAN 的域之间的界面区域，这被证实是由 PMMA 矩阵和刷链之间的熵主导界面能驱动的。基于界面能的半定量估计，建立了状态图，以根据接枝参数和化学相似基体聚合物的分子量，精确预测 NPs 在相分离共混基体中的位置，这也是适用于其他文献中的数据。