核-壳结构P(AM-co-MAA)-W-Ag复合微球的制备  

Preparation of P(AM-co-MAA)-W-Ag Composite Microspheres with Core-Shell Structures

作　　者：吴华涛[1] 张颖[1] 宁向莉[1] 梁红莲[1] 房喻[1] 

机构地区：[1]陕西师范大学化学与材料科学学院,应用表面与胶体化学教育部重点实验室,西安710062

出　　处：《物理化学学报》2008年第4期646-652,共7页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(20373039,20543002);教育部博士点基金(200407188001);陕西省自然科学基金(2007E106)资助项目

摘　　要：以丙烯酰胺(acrylamide,AM)和甲基丙烯酸(methacrylicacid,MAA)的共聚微凝胶(P(AM-co-MAA))为模板,通过离心沉积法将钨粉沉积于高分子微凝胶表面,得到具有核-壳结构的P(AM-co-MAA)-W复合微球;再以经聚乙烯基吡咯烷酮(PVP)修饰的P(AM-co-MAA)-W复合微球为模板,在硝酸银溶液中充分溶胀后,通过向反相悬浮体系中缓慢通入氨气,制备得到了具有核-壳结构的P(AM-co-MAA)-W-Ag双金属复合微球材料.实验发现,通过改变制备过程中AgNO3的初始浓度和PVP的用量等条件,可以改变复合微球表面银的沉积量;并结合实验结果初步提出了银的形成机理,即PVP的存在,不仅可以作为稳定剂固定Ag+离子,同时可以作为还原剂促进Ag+还原为Ag的反应.A method of preparing poly（acrylamide-co-methacrylic acid）-tungsten-silver （P（AM-co-MAA）-W-Ag） composite microspheres with core-shell structures by a copolymer microgel template was described. P（AM-co-MAA）-W composite microspheres were fabricated by centrifugal deposition of tungsten powder on the surface of the polymer template. After absorbing a layer of poly（vinylpyrrolidone） （PVP） on the template of P（AM-co-MAA）-W microspheres and fully immersing them in the AgNO3 aqueous solution, P（AM-co-MAA）-W-Ag composite microspheres were prepared slowly by introducing ammonia gas in the reverse suspension system. It was demonstrated that varying the concentrations of PVP and AgNO3 could modulate the deposition amount of silver on the surface of microspheres. Furthermore, the elementary mechanism of the formation of silver was proposed. The PVP acts both as a stabilizing agent and a reducing agent for the deposition of metal Ag particles.

关 键 词：复合材料 微凝胶 模板法 钨粉 纳米银 

分 类 号：TB383.4[一般工业技术—材料科学与工程]