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Rouse 2D Diffusion of Polymer Chains in Low Density Precursor Films of Polybutadiene Melts
Claire Schune1,2, Marc Yonger1,2, Mohamed Hanafi1
1Soft Matter Sciences and Engineering (SIMM), ESPCI Paris, PSL University, Sorbonne Université, CNRS, F-75005 Paris, France.
Abstract:
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.
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