Shiju Jessy, Al-Sagheer Fakhreia, Ahmad Zahoor
Department of Chemistry, Faculty of Science, Kuwait University, Post Box 5969, Safat-13060, Kuwait.
Polymers (Basel). 2020 Nov 19;12(11):2740. doi: 10.3390/polym12112740.
This paper reports the preparation of Kevlar-Nomex copolymer nano-composites with exfoliated pristine and functionalized graphene sheets (Grs). The graphene oxide (GrO) platelets were amidized by the reaction of amine-terminated aramid (Ar) with the functional groups present on the GrO surface to prepare the nano-composites films with different loadings of GrO. Chemical changes involved during the oxidation and subsequent amidation were monitored by Raman, FTIR and XP spectroscopic analyses. Morphology of the composite films was studied by atomic force and scanning electron microscopies. Viscoelastic properties of the hybrid films were studied for their glass transition temperature (Tg) and storage modulus by dynamical mechanical thermal analysis (DMTA). A higher shift in glass transition temperature was obtained by chemically binding the aramid copolymer chains on the functionalized Gr sheets. The increase in tensile strength and modulus at various loadings of GrO are compared with the composites using pristine Gr. The effect of interfacial interactions between the matrix chains and the reinforcement on the properties of these hybrids have been explained.
本文报道了具有剥离的原始和功能化石墨烯片（Grs）的凯夫拉尔-诺梅克斯共聚物纳米复合材料的制备。通过胺基封端的芳纶（Ar）与氧化石墨烯（GrO）表面存在的官能团反应，使氧化石墨烯（GrO）片层酰胺化，以制备具有不同GrO负载量的纳米复合薄膜。通过拉曼光谱、傅里叶变换红外光谱（FTIR）和X射线光电子能谱（XP）分析监测氧化及后续酰胺化过程中涉及的化学变化。通过原子力显微镜和扫描电子显微镜研究复合薄膜的形态。通过动态热机械分析（DMTA）研究杂化薄膜的粘弹性性质，包括其玻璃化转变温度（Tg）和储能模量。通过将芳纶共聚物链化学结合在功能化的Gr片上，获得了更高的玻璃化转变温度偏移。将不同GrO负载量下的拉伸强度和模量的增加与使用原始Gr的复合材料进行了比较。解释了基体链与增强材料之间的界面相互作用对这些杂化材料性能的影响。
