核/壳结构PS/_MSiO_2复合颗粒的制备和压缩弹性模量  

Synthesis, Characterization and Compressive Elastic Modulus of Core/Shell Structured PS/_MSiO_2 Composite Particles

作　　者：陈杨 左长智 陈爱莲[2] 汪亚运 

机构地区：[1]常州大学材料科学与工程学院,常州213164 [2]常州大学机械工程学院,常州213164

出　　处：《材料研究学报》2018年第2期90-96,共7页Chinese Journal of Materials Research

基　　金：国家自然科学基金(51205032;51405038和51575058)~~

摘　　要：以用聚乙烯吡咯烷酮(PVP)表面修饰的聚苯乙烯(PS,约260 nm)微球为内核并利用PVP与十六烷基三甲基溴化铵之间的液相协同自组装过程,制备出以介孔氧化硅(Mesoporous silica,MSiO_2)为包覆层的核/壳结构PS/MSiO_2复合颗粒。结果表明,在样品壳层中有大量的放射状介孔孔道,壳层的厚度约为60 nm;样品的比表面积为848 g/m2,平均孔径为2.54 nm。根据单个复合颗粒的力曲线,使用Hertz弹性接触模型拟合出样品的压缩弹性模量为(4.47±0.83)(泊松比取值0.33)和(4.89±0.89)GPa(泊松比取值0.2)。对比结果表明,壳层中丰富介孔孔道有利于提高有机/无机复合颗粒的弹性响应。Firstly, polystyrene（PS） microspheres（ca. 260 nm） were surface-modified with polyvinylpyrrolidone（PVP） via a soap-free emulsion polymerization method. Then core-shell composites of PS/MSi O2 with PS as core and mesoporous silica as shell materials were prepared via a synergistic self-assembly process of PVP surfactants and cetyltrimethylammonium bromide micelles. The results indicated that the silica shells were about 60 nm in thickness with radial meso-channels. The specific surface area of the composites and the average pore size of silica meso-channels were 848 g/m2 and 2.54 nm, respectively.The compressive elastic moduli（E） of the individual composite particle were assessed by analyzing the force-displacement curves, measured by scanning probe microscopy, on the basis of the Hertz contact model. The fitted and calculated E values were 4.47 ± 0.83（Poisson＇s ratio=0.33） and 4.89 ± 0.89 GPa（Poisson＇s ratio=0.2）, respectively. These results suggest that the improvement of the elastic response of organic/inorganic composite particles may be ascribed to the presence of mesoporous shells, indicating a potential application in optimizing the structural design of novel non-rigid composite abrasives.

关 键 词：复合材料 颗粒 核壳结构 扫描探针显微镜 压缩弹性模量 Hertz模型 

分 类 号：TB383[一般工业技术—材料科学与工程]