高分散性SiO_2/PMMA复合材料的制备与表征--稀释分散性  

PREPARATION AND CHARACTERIZATION OF SILICA/PMMA COMPOSITES WITH HIGHLY DISPERSED SILICA——DISPERSIBILITY

作　　者：戚栋明[1,2] 张睿[2] 徐杰[1] 申兴丛[1] 吴明华[1] 

机构地区：[1]浙江理工大学生态染整技术教育部工程研究中心,杭州310018 [2]浙江理工大学先进纺织材料与制备技术教育部重点实验室,杭州310018

出　　处：《高分子学报》2012年第5期528-533,共6页Acta Polymerica Sinica

基　　金：国家自然科学基金项目(基金号50803058,51073142);浙江省自然科学基金项目(基金号Y4100221);浙江理工大学研究生创新基金项目(YCX-S11004);浙江省重点创新团队资助项目(2010R50038)

摘　　要：以高无机含量SiO2/聚甲基丙烯酸甲酯(PMMA)接枝复合材料为预分散母料,与PMMA树脂进行熔融共混,制得低无机含量的SiO2/PMMA复合材料.通过切片透射电镜(TEM)观察熔融共混过程中预分散母料内堆积SiO2粒子分散状态的演化.发现预分散母料接枝状态对其影响最为显著,不经接枝修饰的SiO2粒子经熔融共混后,不可避免地会在熔体中产生大量亚微米级的立体团聚体;复杂接枝预分散母料内构成以SiO2粒子为交联点的立体交联结构,其中的堆积SiO2粒子不能在剪切场中得到有效解离和释放;只有在使用简单接枝预分散母料时,基体高分子链才能不断地渗透扩散进入预分散母料内,而预分散母料可被不断地溶胀和撕裂,因而其中的堆积SiO2才可不断地向基体相迁移和扩散,并最终在整个复合材料内实现初级粒子形式的高度均匀稳定分散.Silica/poly（methyl methacrylate） grafting composites（SiO2/PMMA） with higher silica content were used as pre-dispersed masterbatches and melt-mixed with PMMA resin to prepare a series of SiO2/PMMA composites with lower silica content.The dispersion evolution of accumulated silica particles during melt-mixing process was monitored by section-TEM.It was found that the effect of grafting states of pre-dispersed masterbatches on the dispersibility of accumulated silica particles was obvious.Non-grafted silica particles were easily agglomerated into sub-micron level aggregation in PMMA melt due to their poor compatibility.Taking silica particles as cross-linking points,three-dimensional cross-linked structure was generally formed in complex grafted pre-dispersed masterbatche,and as a result the accumulated silica particles can＇t be released and then diffused into the matrix phase.Only the simple grafted pre-dispersed masterbatche can be swelled by the matrix polymer and then be torn by the strong shear field force,in this case the accumulated silica particles can constantly migrated from pre-dispersed masterbatche phase into matrix phase,and finally can be uniformly dispersed in the entire matrix phase at a primary-particles size level.This high silica dispersion was of benefit to improving the composite properties.

关 键 词：纳米SIO2 接枝状态 熔融共混 可分散性 

分 类 号：TB33[一般工业技术—材料科学与工程]