Interfacial Interactions During InSitu Polymer Imbibition in Nanopores.

Chien-Hua Tu,Masao Doi,Jiajia Zhou,Hans-Juergen Butt,George Floudas

doi:10.1103/physrevlett.125.127802

Abstract

Using insitu nanodielectric spectroscopy we demonstrate that the imbibition kinetics of cis-1,4-polyisoprene in native alumina nanopores proceeds in two time regimes both with higher effective viscosity than bulk. This finding is discussed by a microscopic picture that considers the competition from an increasing number of chains entering the pores and a decreasing number of fluctuating chain ends. The latter is a direct manifestation of increasing adsorption sites during flow. At the same time, the longest normal mode is somewhat longer than in bulk. This could reflect an increasing density of topological constraints of chains entering the pores with the longer loops formed by other chains.

Highlights

Using in situ nanodielectric spectroscopy we demonstrate that the imbibition kinetics of cis-1,4polyisoprene in native alumina nanopores proceeds in two time regimes both with higher effective viscosity than bulk
Understanding that way that polymers penetrate in narrow pores is important for applications including separation of proteins with relevance in cell biology and the development of inkjet printing for commercial xerography
When the openings of the pores are brought into contact with a polymer melt, capillary forces drive the polymer chains into the pores

Summary

Interfacial Interactions During In Situ Polymer Imbibition in Nanopores

Chien-Hua Tu ,1 Jiajia Zhou ,2,3 Masao Doi ,3 Hans-Juergen Butt, and George Floudas 1,4,5,*. Using in situ nanodielectric spectroscopy we demonstrate that the imbibition kinetics of cis-1,4polyisoprene in native alumina nanopores proceeds in two time regimes both with higher effective viscosity than bulk. This finding is discussed by a microscopic picture that considers the competition from an increasing number of chains entering the pores and a decreasing number of fluctuating chain ends. In this Letter we employ the nanofluidic method to follow the in situ polymer dynamics directly at the chain length scale by studying the evolution of normal modes in cis-1,4-polyisoprene (PI) during imbibition in AAO nanopores. The electric filed is applied in the z direction (flow direction), the z component of the polarization is detected

Published by the American Physical Society

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