We took advantage of pseudopartial wetting to promote the spreading of precursor films whose surface density smoothly decays to zero away from a sessile droplet. By following the spreading dynamics of semidilute precursor films of polybutadiene melts on silicon wafers, we measure molecular diffusion coefficients for different molar masses and temperatures. For homopolymers, chains follow a thermally activated 2D Rouse diffusion mechanism, with an activation energy revealing polymer segment interactions with the surface. This Rouse model is generalized to chains with specific terminal groups.

中文翻译：

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聚丁二烯熔体低密度前体膜中聚合物链的 Rouse 二维扩散

我们利用伪部分润湿来促进前体薄膜的扩散，其表面密度从固着液滴平稳衰减到零。通过跟踪聚丁二烯半稀释前体薄膜在硅晶片上的扩散动力学，我们测量了不同摩尔质量和温度下的分子扩散系数。对于均聚物，链遵循热激活的 2D Rouse 扩散机制，其活化能揭示聚合物链段与表面的相互作用。这个 Rouse 模型被推广到具有特定终端组的链。