Improving Impact Toughness of Polylactide/Ethylene-co-vinyl-acetate Blends via Adding Fumed Silica Nanoparticles:Effects of Specific Surface Area-dependent Interfacial Selective Distribution of Silica  

作　　者：Ting-Ting Zhang Mei-Xi Zhou Zhen-You Guo You-Bo Zhao Di Han Hao Xiu Hong-Wei Bai Qin Zhang Qiang Fu 

机构地区：[1]College of Polymer Science and Engineering,State Key Laboratory of Polymer Materials Engineering,Sichuan University,Chengdu 610065,China

出　　处：《Chinese Journal of Polymer Science》2021年第8期1040-1049,I0008,共11页高分子科学（英文版）

基　　金：the National Natural Science Foundation of China(No.51803130);China Postdoctoral Science Foundation(No.2018M640915);Sichuan Science and Technology Program(No.2019JDRC010);Fundamental Research Funds for Central Universities.

摘　　要：Adding fumed silica(Si0_(2))has been considered as an effective method for tailoring the phase morphology and performance of elastomer-toughened plastic binary blends.It has been demonstrated that the selective distribution of SiO_(2) plays a decisive role in the mechanical properties of plastic/elastomer/SiO_(2)nanocomposites,especially for the impact toughness.In this work,we aim to illuminate the role of specific surface area in controlling their selective distribution of fumed SiO_(2) and consequent mechanical properties of plastic/elastomer binary blends.Three types of SiO_(2) with different specific surface areas were incorporated into polylactide/ethylene-co-vinyl-acetate(PLA/EVA)model blends by melt blending directly.It was found that the selective distribution of SiO_(2) is largely determined by their specific surface areas,i.e.SiO_(2) nanoparticles with low specific surface area has a stronger tendency to be located at the interface between PLA matrix and EVA dispersed phase as compared to those with high specific surface area.The specific surface area-dependent interfacial selective distribution of SiO_(2) is mainly attributed to the extent of increased viscosity of EVA dispersed phase in which SiO_(2)nanoparticles are initially dispersed and resultant migration rate of SiO_(2) nanoparticles.The interfacial localized SiO_(2) nanoparticles induce an obvious enhancement in the impact toughness with strength and modulus well maintained.More importantly,in the case of the same interfacial distribution,toughening efficiency is increased with the specific surface area of SiO_(2).Therefore,this is an optimum specific surface area of SiO_(2) for the toughening.This work not only provides a novel way to manipulate the selective distribution of SiO_(2) in elastomer-toughened plastic blends toward high-performance,but also gives a deep insight into the role of interfacial localized nanoparticles in the toughening mechanism.

关 键 词：Fumed silica Specific surface area Selective distribution POLYLACTIDE Impact toughness 

分 类 号：TQ320.1[化学工程—合成树脂塑料工业] TB383.1[一般工业技术—材料科学与工程]