界面接枝聚合制备有机/无机核壳粒子及聚合物微胶囊

Organic/inorganic core-shell microspheres and polymer microcapsules prepared through interfacial graft polymerization

采用界面接枝聚合法成功制备了粒径与壳厚均匀、可控的SiO2/PMMA核壳粒子及PMMA微胶囊。研究发现,单体用量是影响聚合物壳层厚度的重要因素,随MMA用量增加,SiO2/PMMA核壳粒子壳层变厚,其由单纯化学键转向化学键与物理缠结并存。当MMA用量超过SiO2总表面所能消耗的单体最大值时,MMA将均相成核,形成的聚合物乳胶粒子与核壳粒子并存于反应产物中。TEM、FTIR、DLS分析结果表明,PMMA外壳通过共价键锚固在SiO2表面,实现了对其的包覆,证实了核壳结构、空心结构的形成。

Interfacial graft polymerization was employed to prepare Si02/PMMA core-shell microspheres and PM MA microcapsules with uniform, controlled size and shell thickness. The results showed that MMA concentration was a key factor to control the polymer shell thickness. With increasing the monomer concentration, the PMMA shell thickness increased. In the inner of the shell, PMMA was combined with inorganic core through covalent bond. In the outer of shell, however, polymer chains entangled each other by aggradation. When the whole surface of SiO2 microspheres were occu pied, homogeneous nucleation occurred, resulting in the formation of pure PMMA latex particles that coexisted with SiO2/ PMMA core-shell rnicrospheres. TEM, FTIR and DLS revealed that PMMA encapsulated SlOe cores strongly through chemical bonds. And the core--shell and hollow structures were also proved.