原子模型分析无定型聚合物在单轴拉伸下的机械行为

Analysis of the mechanical behavior of polymer in an amorphous state under uniaxial extension condition through atomistic modeling

用原子模型法研究双酚-A-聚碳酸酯无定型态聚合物在单轴拉伸下的机械行为。材料密度、x-ray散射、应力-应变曲线等计算结果与实验数据吻合,证实模型结构正确,力场选择合理。拉伸模拟中构象变化的苯环、碳原子和亚异丙基基团的运动一目了然。能量分析表明,二面角扭转能和VDW相互作用能在拉伸形变中,扮演了比较重要的角色。

The mechanical behavior of bis-phenol-A-polycarbonate （BPA-PC）in an amorphous state was simulated under uniaxial extension conditions through atomistic modeling. The mechanical properties,like the density, x-ray scattering and stress-strain diagram,obtained from the well-defined structure and suitably adopted force field were comparable with those obtained from experiments. Extension simulation distinguished the movement between phenyl, carbon and subcymene clearly. Energy analyses show that the dihedral angle torsion energy and the van der Waals interaction energy play important roles in deformation under uniaxial extension.