Nanowear in a nanocomposite reinforced polymer
Nanowear in a nanocomposite reinforced polymer
复制标题
DOI：
10.1016/j.wear.2011.05.040
复制
发表时间：
2011-09-02
期刊：
影响因子：
5
通讯作者：
Berger, Ruediger
中科院分区：
文献类型：
--
作者：
Pihan, Sascha A.;Emmerling, Sebastian G. J.;Berger, Ruediger
我们在纳米尺度上研究了聚甲基丙烯酸乙酯（PEMA）和PEMA接枝纳米颗粒共混物的增强性能。利用扫描力显微镜（SFM）进行纳米磨损实验。除了成像外，SFM还应用于纳米颗粒长度尺度的样品表面磨损。通过改变纳米颗粒接枝聚合物的分子量(N)和形成基体的聚合物的分子量(P)，制备了不同混相的纳米颗粒共混物。通过分析纳米磨损实验中不同正常载荷产生的纳米磨损模式，我们能够将纳米磨损发生的临界力联系起来。该临界力的定义允许对不同组成的纳米粒子-聚合物体系进行定量比较。纳米磨损试验表明，与纯均聚物相比，只有含有N/P>1的混合物增强了复合材料。在这些条件下，接枝的聚合物膨胀，纳米颗粒作为额外的锚点。作为参考实验，我们使用了由PEMA均聚物和未改性颗粒制成的共混物。未接枝的纳米颗粒显然不能解释任何强化。(C) 2011 Elsevier B.V.版权所有
We investigated the reinforcement of blends made from poly(ethyl methacrylate) (PEMA) and PEMA-grafted nanoparticles at a nanometer length scale. The reinforcement was probed by nanowear experiments based on scanning force microscopy (SFM). In addition to imaging, the SFM is applied to wear the surface of samples at the length scale of nanoparticles. Blends with different miscibility of nanoparticles were prepared by varying the molecular weights of polymer grafted from the nanoparticles (N) and polymer forming the matrix (P). We were able to associate a critical force for the onset of nanowear by analyzing the nanowear patterns resulting from different normal loads during the nanowear experiment. The definition of this critical force allows quantitative comparison of nanoparticle-polymer systems of different composition. Nanowear tests indicated that only mixtures where N/P>1 reinforced the composite material compared to the pure homopolymer. Under these conditions the grafted polymers were swollen and the nanoparticles acted as additional anchor sites. As reference experiments we used a blend made from PEMA homopolymer and unmodified particles. Non-grafted nanoparticles clearly did not account for any reinforcement. (C) 2011 Elsevier B.V. All rights reserved.