Molecular transport characteristics of a chlorosulfonated polyethylene geomembrane in the presence of aromatic esters

Abstract

Results of a study on sorption and diffusion of chlorosulfonated polyethylene geomembrane with methyl benzoate, ethyl benzoate, methyl salicylate, iso‐butyl salicylate, phenyl acetate, and diethyl phthalate in the temperature range 25–60°C are presented. A gravimetric sorption method is used to calculate the diffusion and permeation coefficients from the Fickian relationship. The diffusion results are dependent on penetrant–membrane interactions, temperature, and on penetrant concentration. The values of diffusion coefficients range from 0·02 × 10−7 cm2 s−1 for diethyl phthalate at 25°C to 1·81 × 10−7 cm2 s−1 for ethyl benzoate at 60°C. The activation energies for diffusion range from 21 to 50 kJ mol−1. The values of heat of sorption ranged between 2·2 and 6·4 kJ mol−1. Sorption results are also analyzed using a first‐order sorption kinetic equation. Experimental results and calculated parameters are used to discuss the transport behavior. None of the esters used have shown any chemical attack toward the geomembrane.

Adsorption and desorption properties of the chelating membranes prepared from the PE films

“…In addition, the kinetic constants of adsorption were calculated from the slope of the linear relationship between the immersion time and ln (1ϪQ t / Q eq ) value. 32,33 Here, the adsorption of Cu 2ϩ ions on the IDA-(PE-g-PGMA) films was assumed to proceed like a first-order reaction, and the kinetic constants of adsorption, k, were calculated using eq. (1):…”

Theoretical and experimental investigations of molecular migration and diffusion kinetics of organic esters into tetrafluoroethylene/propylene copolymer membranes

“…E-mail address: unikard@ren.nic.in reverse osmosis (Sourirajan, 1970), chemical pond lining (Ortego et al, 1995;Aminabhavi et al, 1995) and controlled drug delivery (Kulkami et al, 1990;Kulkami et al, 1992). These varied applications provide motivation for determining the relationships between difbivity and molecular size of the mobile penetrants.…”

“…Moreover, this is an important practical problem because the sorbed solvent molecules often cause degradation of the physical and/or mechanical properties of the membrane materials. Although numerous studies have been carried out on solvent sorption and diffusion into glassy and rubbery polymer membranes (Aminabhavi et al, 1995;Aminabhavi and Phayde, 1995a,b;Munnolli, 1994, 1995;Harogoppad and Aminabhavi, 1991;Vergnaud, 1991 ;Senoune and Vergnaud, 1992;Franson and Peppas, 1983;Lucht and Peppas, 1987), there are virtually no detailed reports on the transport characteristics of 3M's tetrafluoroethylene/propylene copolymer membranes in the presence of aliphatic esters. For successful membrane applications, polymers must be tested as to their exposure to varying solvent media.…”

“…In recent years, there has been a fundamental and widespread interest in the sorptive migration and diffusive kinetics of organic liquids into polymers related to a variety of industrial processes including pervaporation , barrier packaging (Tsai and Wachtel, 1990), *Author to whom correspondence should be addressed. E-mail address: unikard@ren.nic.in reverse osmosis (Sourirajan, 1970), chemical pond lining (Ortego et al, 1995;Aminabhavi et al, 1995) and controlled drug delivery (Kulkami et al, 1990;Kulkami et al, 1992). These varied applications provide motivation for determining the relationships between difbivity and molecular size of the mobile penetrants.…”

Non-Fickian diffusion in systems with complex interfaces

“…22,23 Diffusion occurs via the movement of individual molecules. Solubility is determined by many factors including the chemical nature of the polymer and the penetrating species such as hydrogen bonding, dipole interactions, molecular size and shape of the permeating species, etc.…”