Interfacial Interactions During In Situ Polymer Imbibition in Nanopores

Abstract

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. 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.

Adsorption Kinetics of cis-1,4-Polyisoprene in Nanopores by In Situ Nanodielectric Spectroscopy

“…In a recent study, 14 we have employed a type A polymer, i.e., a polymer having components of dipole moment both perpendicular and along the polymer backbone. We could show that interfacial interactions develop already during the polymer flow in nanopores.…”

“…In this endeavor, techniques that can provide simultaneous access to the kinetics of imbibition and to the molecular dynamics during and after flow are advantageous. A recent development in this direction has been the implementation of the nanodielectric spectroscopy ( n DS) technique to follow the imbibition of polymers in nanopores. − In this technique, a capacitor is formed by the two surfaces of a nanoporous aluminum template and an ac field is applied along the pore axis. A polymer melt on the top surface of a template will penetrate the pores by capillary action.…”

“…For the confining medium, we employ self-ordered nanoporous aluminum oxide (AAO) that contains arrays of parallel cylindrical nanopores uniform in length (pore depth = 100 μm) and diameter (pore diameters = 100, 40, and 20 nm) that can easily be infiltrated from the melt . In contrast to the earlier study, here, we are interested in the long-time adsorption kinetics following the full imbibition. The aim is to establish scaling laws for the adsorption time as a function of pore size and molecular mass.…”

A decade of innovation and progress in understanding the morphology and structure of heterogeneous polymers in rigid confinement

“…Dynamics of homopolymers were studied for numerous homopolymers, either entangled or unentangled polymers. Typical studied polymers were polyisoprene (PI) [159][160][161] ,poly(1,4-butadiene) (PBD) [162][163][164][165] polyethylene oxide (PEO) 166 , PVDF 138 , PDLLA 135 , PCL 48 , PPG [167][168] , poly(methylphenylsiloxane) 169 , poly(dimethylsiloxane) 170 , polyethylene-alt-propylene (PEP). 171 The higher the interfacial energy is, the higher Adrjanowicz et al 169 studied the dynamical behavior of poly(methylphenylsiloxane) (Mw=21k) inside AAO pores with diameter ranging from 10 to 120 nm and its pressure dependence.…”

Capillary filling in drop merging: dynamics of the four-phase contact point

“…Capillarity driven filling in capillaries and V-shaped grooves is both long studied problem and still an active field of research. This is due to the fact that passive capillary flow inside macro and micro channels are used in wide range of applications like microfluidics [18,19], printing technologies [20], capillary pumping [21] or liquid imbibition in different scales [22,23] . More than three centuries ago, Hauksbee and Jurin published first accounts on the static shape of a water meniscus in the wedge between two touching glass plates [24][25][26].…”