ABSTRACT

Graphene is synthesized and characterized using rice husk as a source with carbonization and potassium hydroxide (KOH) activation process. It has functional groups at the edges with a smooth surface. Graphene is melt-mixed with 50/50 (wt/wt) polypropylene (PP)/polyamine-6 (PA6) in the presence and absence of a compatibilizer. The compatibilizer used is polypropylene grafted maleic anhydride (PP-g-MA). There is a reaction between PP-g-MA and PA6 phase as established from FTIR spectroscopy. All samples show the formation of complex morphology with compatibilization and graphene addition in 50/50 (wt/wt) PP/PA6 blend. Graphene is localized in PA6 phase of 50/50 (wt/wt) PP/PA6 blend and its nanocomposites in the presence and absence of PP-g-MA. All the samples have power-law index (n) value of less than one exhibiting pseudoplastic fluid behavior; n values are significantly higher after compatibilization and graphene addition in 50/50 (wt/wt) PP/PA6 blend as reveals from rheological measurements. Graphene addition influences the crystallization behavior with selective localization in PA6 phase and morphology development. Dynamic mechanical analysis (DMA) shows improved stiffness of 50/50 (wt/wt) PP/PA6 blend with an addition of graphene and PP-g-MA. Tensile and impact properties increases are highest with an addition of 1 wt.% of graphene in 50/50 (wt/wt) PP/PA6 blend in presence of PP-g-MA.

摘要

石墨烯以稻壳为原料，经碳化和氢氧化钾 (KOH) 活化工艺合成并表征。它在边缘有官能团，表面光滑。在增容剂存在和不存在的情况下，石墨烯与 50/50 (wt/wt) 聚丙烯 (PP)/聚胺 6 (PA6) 熔融混合。所用的增容剂是聚丙烯接枝马来酸酐（PP-g-MA）。根据 FTIR 光谱，PP-g-MA 和 PA6 相之间存在反应。所有样品均显示在 50/50 (wt/wt) PP/PA6 共混物中通过增容和添加石墨烯形成了复杂的形态。在存在和不存在 PP-g-MA 的情况下，石墨烯定位于 50/50 (wt/wt) PP/PA6 混合物及其纳米复合材料的 PA6 相中。所有样品的幂律指数 (n) 值均小于 1，表现出假塑性流体行为；从流变测量中可以看出，在 50/50 (wt/wt) PP/PA6 共混物中增容和添加石墨烯后，n 值显着升高。石墨烯的添加通过选择性定位在 PA6 相和形态发展中影响结晶行为。动态机械分析 (DMA) 显示，添加石墨烯和 PP-g-MA 后，50/50 (wt/wt) PP/PA6 混合物的刚度得到改善。在 PP-g-MA 存在的情况下，在 50/50 (wt/wt) PP/PA6 混合物中添加 1 wt.% 的石墨烯，拉伸和冲击性能的提高最高。动态机械分析 (DMA) 显示，添加石墨烯和 PP-g-MA 后，50/50 (wt/wt) PP/PA6 混合物的刚度得到改善。在 PP-g-MA 存在的情况下，在 50/50 (wt/wt) PP/PA6 混合物中添加 1 wt.% 的石墨烯，拉伸和冲击性能的提高最高。动态机械分析 (DMA) 显示，添加石墨烯和 PP-g-MA 后，50/50 (wt/wt) PP/PA6 混合物的刚度得到改善。在 PP-g-MA 存在的情况下，在 50/50 (wt/wt) PP/PA6 混合物中添加 1 wt.% 的石墨烯，拉伸和冲击性能的提高最高。