静电层层自组装制备聚苯乙烯微球(核)/MCM-41纳米粒子(壳)阶层结构复合微粒

采用聚苯乙烯磺酸钠(PSS)和聚二烯丙基二甲基氯化铵(PDDA)两种聚电解质, 通过静电层层自组装成功地将MCM-41介孔二氧化硅纳米粒子包覆到聚苯乙烯(PS)微球表面. 实验结果表明, 当以尺寸为1.4 μm的PS微球为核时, 包覆了两个聚电解质双层(PDDA/PSS)2的PS(PDDA/PSS)2(PDDA/MCM-41)复合结构微粒与包覆了一个聚电解质双层(PDDA/PSS)的PS(PDDA/PSS)(PDDA/MCM-41)复合结构微粒相比, 复合结构微粒之间的交联程度降低, 但是MCM-41纳米粒子在聚苯乙烯微球表面的包覆都比较松散, 且产物中存在大量杂质. 而当以尺寸为5 μm的聚苯乙烯微球为核时, MCM-41纳米粒子紧密地包覆在聚苯乙烯微球表面, 复合结构微粒之间只有少量桥连物, 且产物中杂质很少.

Preparation of Hierarchical Polystyrene Microsphere (Core)/MCM-41 Nanoparticle (Shell) Composite Particles via Electrostatic Layer-by-layer Assembly

MCM-41 Nanoparticles were successfully coated on the surface of polystyrene (PS) microspheres via electrostatic layer-by-layer assembly by using two polyelectrolytes, i.e., sodium poly(4-styrenesulfonate) (PSS) and poly(diallyldimethylammonium) (PDDA). The experimental results showed that when monodisperse PS microspheres of ca. 1.4 μm in diameter were used as core, composite microparticles coated with two prime polyelectrolyte bilayers (PDDA/PSS)2, i.e., PS(PDDA/PSS)2(PDDA/MCM-41), aggregated to a less extent than those coated with a single prime polyelectrolyte bilayer (PDDA/PSS), i.e., PS(PDDA/PSS)(PDDA/MCM-41). However, the covering of MCM-41 nanoparticles was incompact on the surface of PS microspheres in both cases, and there were many impurities in the final products. When monodisperse PS microspheres of 5 μm in diameter were used as core, MCM-41 nanoparticles were densely coated on the surface of PS microspheres.