硫化物-高分子复合微球表面形貌与模板组成关系的研究

以N-异丙基丙烯酰胺(NIPAM)和甲基丙烯酸(MAA)为单体, 通过反相悬浮聚合法制备了多种MAA含量不同的阴离子型P(NIPAM-co-MAA)共聚微凝胶. 以这些共聚微凝胶为模板, 在不同表面活性剂存在下, 合成了一系列CuS(CdS、ZnS)-P(NIPAM-co-MAA)无机-有机复合微球材料, 研究了表面活性剂种类, 模板组成等因素对上述硫化物-高分子复合微球表面形貌的影响. 结果表明, 实验条件下所得复合微球表面均具有图案化结构, 该结构明显依赖于表面活性剂的种类和模板微凝胶的组成. 就模型体系而言, 随表面活性剂Span-20、Span-80和Span-85的HLB(亲水亲油平衡)值降低, 微球表面形貌趋于粗糙, 但仍然十分规整; 就模板组成而言, 模板中MAA含量增加使得复合微球的表面形貌变得更加精细. 据此, 认为通过选用合适的表面活性剂和微凝胶模板可以在一定范围内调控这些无机-有机复合微球的表面形貌, 从而为后续应用研究奠定基础.

Studies on the Template Composition Dependence of the Surface Morphology of the Metal Sulfides-P(NIPAM-co- MAA) Composite Microspheres

N-isopropylacrylamide (NIPAM) and methacrylic acid (MAA) copolymer microspheres with various compositions were prepared by inverse suspension polymerization technique. The microgels thus prepared were employed as templates for the deposition of MS (M = Cu, Cd or Zn). In this way, a number of MS (M = Cu, Cd or Zn)-P(NIPAM-co-MAA) composite microspheres with different surface morphologies were prepared successfully. The effects of surfactants and the composition of the microgels upon the surface morphologies of the composite microspheres were studied in detail. It was demonstrated that the structures of the surfactants and the compositions of the microgels employed in the preparation have a great effect upon the surface morphologies of the composite microspheres. As for the model systems, the surface structures of the composite microspheres tend to be coarse with the structures of the surfactants becoming complex, or with their HLB(hydrophile-lipophile balance) values decreasing (Span-20, Span-80, and Span-85). Even so, the surface structures of the composite microspheres prepared in the presence of Span-85 are still highly ordered. It was also demonstrated that more fine surface structures were formed with increasing the MAA content in the template microgels. Thus, it may be concluded that the surface structures of the composite microspheres can be tailored to a certain extent by simply varying the types of surfactants, and changing the composition of monomer units in the template microgels.