Controlling and understanding the flow properties of polymer nanocomposites (PNC) is very important in realising their potential for various applications. In this study we report molecular dynamics simulation studies of slip between a rotating polymer-grafted nanoparticle and the surrounding free linear matrix chains. By varying the interface wettability between the nanoparticle and matrix chains defined by the parameter f, the ratio of the graft to the matrix chain length, or the graft chain density, Σ, we were able to tune the interface slip, δ, significantly. Both f and Σ alter the interface wettability by changing the matrix chain penetration depth, λ, into the graft chain layer. We observed a large value of δ at smaller f or Σ which reduces with an increasing value of the respective parameters. Since interface slip is also likely to affect other properies of PNCs, like viscosity and the glass transition, we suggest that these parameters could become useful tools to control the flow and mechanical properties of PNCs made with grafted nanoparticles.

中文翻译：

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接枝纳米颗粒-基体聚合物界面润湿性与聚合物纳米复合材料的滑度之间的相关性

控制和理解聚合物纳米复合材料（PNC）的流动特性对于实现其在各种应用中的潜力非常重要。在这项研究中，我们报告了分子动力学模拟研究旋转聚合物接枝的纳米粒子和周围的自由线性矩阵链之间的滑动。通过改变由参数f定义的纳米颗粒与基质链之间的界面润湿性，接枝与基质链长度之比或接枝链密度Σ，我们能够显着调整界面滑移δ。f和Σ都通过改变基质链渗透深度λ来改变界面润湿性，进入嫁接链层。我们在较小的f或Σ处观察到较大的δ值，该值随各个参数值​​的增加而减小。由于界面滑移也可能会影响PNC的其他性能，例如粘度和玻璃化转变，我们建议这些参数可能成为控制用接枝纳米颗粒制成的PNC的流动性和机械性能的有用工具。