福建师范大学章华桂团队近日研究了刷状聚苯乙烯（PS）-SiO₂-聚甲基丙烯酸2-羟乙酯Janus纳米颗粒的一步法制备，以增容PS/聚甲基丙烯酸甲酯共混物。相关论文于2025年5月14日发表在《中国高分子科学杂志 》上。

增容是非混相聚合物共混发展高性能复合材料的关键；然而，传统的共聚物增容（预制或原位生成）存在界面锚定弱的问题，无机颗粒由于其界面解吸能大而受到广泛关注，但其对大块组分的亲和力低是一个缺点。

研究组采用界面原子转移自由基聚合（ATRP）技术在Br功能化SiO₂纳米颗粒的不同半球上同时生长聚苯乙烯（PS）和聚（2-甲基丙烯酸羟乙酯）（PHEMA），以稳定Pickering乳液，从而开发出刷状Janus纳米颗粒（SiO₂@JNP）。并通过透射电子显微镜（TEM）观察了作为对照样品的SiO₂-PS单半球接枝的Janus特征。

SiO₂@JNP被证明是PS/聚甲基丙烯酸甲酯（PMMA）非混相共混物的有效增容剂，并且液滴基质形态显著改善。在低含量SiO₂@JNP优化~0.9 wt%时，共混物的机械强度和韧性同步增强，抗拉强度、断裂伸长率和冲击强度分别提高了17.7%、26.6%和19.6%。这种增强可能归因于接枝聚合物基体和单个组分之间的缠结，这些缠结改善了颗粒-体相亲和性并加强了界面粘附。

附：英文原文

Title: One-step Preparation of Brush-type Polystyrene (PS)-SiO2- poly(2-hydroxyethyl methacrylate) Janus Nanoparticle to Compatibilize PS/Poly(methyl methacrylate) Blends

Author: Feng-Yuan Tu, Ming-Feng Wang, Gang Zhong, Hua-Wei Qiao, Bo-Tuo Zheng, Can-Pei Liu, Ming-Feng Chen, Hua-Gui Zhang

Issue&Volume: 2025-05-14

Abstract: Compatibilization is crucial for the blending of immiscible polymers to develop high-performance composites; however, traditional compatibilization by copolymers (pre-made or in-situ generation) suffers from weak interface anchoring, and inorganic particles have gained extensive attention recently owing to their large interfacial desorption energy, while their low affinity to bulk components is a drawback. In this study, an interfacial atom transfer radical polymerization (ATRP) technique was employed to grow polystyrene (PS) and poly(2-hydroxyethyl methacrylate)(PHEMA) simultaneously on different hemispheres of Br-functionalized SiO2 nanoparticles to stabilize a Pickering emulsion, whereby a brush-type Janus nanoparticle (SiO2@JNP) was developed. The polymer brushes were well-characterized, and the Janus feature was validated by Transmission electron microscope (TEM) observation of the sole hemisphere grafting of SiO2-PS as a control sample. SiO2@JNP was demonstrated to be an efficient compatibilizer for a PS/poly(methyl methacrylate) (PMMA) immiscible blend, and the droplet-matrix morphology was significantly refined. The mechanical strength and toughness of the blend were synchronously enhanced at a low content SiO2@JNP optimized ~0.9 wt%, with the tensile strength, elongation-at-break and impact strength increased by 17.7%, 26.6% and 19.6%, respectively. This enhancement may be attributed to the entanglements between the grafted polymer brushes and individual components that improve the particle-bulk phase affinity and enforce interfacial adhesion.

DOI: 10.1007/s10118-025-3357-z

Source: https://www.cjps.org/en/article/doi/10.1007/s10118-025-3357-z/