This simulation studied graphene functionalized with methyl (CH₃), hydroxyl (OH), carboxyl (COOH), and amine (NH₂) groups as potential nanofillers for polylactide (PLA) biodegradable polymers. Key properties including the structure and dynamics of polymer chains, interaction energy and interfacial shear force between the polymer matrix and the filler, and glass transition temperature (T_g) of the nanocomposites were investigated. Results indicated that graphene functional groups play important roles in the interfacial bonding characteristics between polymer matrix and the filler. Among the fillers studied, graphene modified by COOH groups provided the strongest enhancement of interfacial interaction and shear force between the PLA matrix and the filler. The presence of nanofillers resulted in a moderate shift of the composite T_g compared to the unfilled polymer. The system with stronger interfacial interaction possessed higher T_g due to lower mobility of chain segments induced by the interaction strength between the polymer and the filler.

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功能化石墨烯作为聚丙交酯的纳米填料：分子动力学模拟研究

这种模拟研究石墨烯与甲基（官能 CH ₃），羟基（ OH），羧基（ COOH），和胺（ NH ₂）基团作为聚乳酸潜在纳米填料（PLA）可生物降解的聚合物。研究了包括聚合物链的结构和动力学，聚合物基体与填料之间的相互作用能和界面剪切力以及纳米复合材料的玻璃化转变温度（T _g）在内的关键特性。结果表明，石墨烯官能团在聚合物基体与填料之间的界面键合特性中起重要作用。在研究的填料中，石墨烯被改性COOH基团提供了PLA基质与填料之间的界面相互作用和剪切力的最强增强。与未填充的聚合物相比，纳米填充剂的存在导致复合材料T _g的中等偏移。由于聚合物与填料之间的相互作用强度引起的链段迁移率较低，界面相互作用较强的系统具有较高的T _g。