中文摘要：

利用显微-光学剪切联用系统构造受限剪切环境,探讨了少量不同表面性质的SiO2纳米粒子的加入对聚异丁烯（PIB）/聚二甲基硅氧烷（PDMS）不相容共混体系分散相形态演变过程的影响.研究结果表明,少量疏水性SiO2纳米粒子的加入可抑制分散相液滴的凝聚,从而抑制珍珠链状及纤维状等超级相形态的形成,使共混物表现为近似本体流体的行为.少量亲水性SiO2纳米粒子的加入仍能使共混体系在特定条件下形成超级相形态,但会导致剪切停止后的分散相动力学回缩过程变慢;只有在较高粒子含量及剪切速率下分散相液滴的形态才有向本体行为转变的趋势.

英文摘要：

The morphology development in immiscible polymer blends under confined shear flow（such as in the field of micro-processing） usually differs significantly to that observed in bulk conditions.In this work,the effect of silica nanoparticles with different surface properties on the morphology development of immiscible polyisobutylene（PIB）/polydimethylsiloxane（PDMS）（10∶ 90） blends under confined shear flow was investigated.The confined environment was created by an optical-shear cell united system.It was found that the addition of only a very small amount（0.2%） of hydrophobic SiO2 nanoparticles could suppress the coalescence of dispersed droplets effectively and thus decreased the confinement degree of droplets.As a result,the formation of the superstructures（such as pearl necklaces and strings）,as presented in the pure PIB/PDMS blends,were prevented and the blends displayed a near bulk behavior.On the contrary,the blends with the addition of small amount of hydrophilic SiO2 nanoparticles still formed superstructures of dispersed droplets under shear flow.Bulk behavior of dispersed phase could only be obtained with higher concentration of the hydrophilic SiO2 nanoparticles and under higher shear rate.