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Sorption and diffusion of n-alkanes into bromobutyl rubber membranes were investigated in the temperature interval 25-60°C by a sorption gravimetric method. The Fickian diffusion equation was used to calculate the diffusion coefficients, which were dependent on the size of the alkanes, their interactions with the chain segments of the polymer and temperature. The diffusion coefficients varied from 0.34 x 10-'cm2/s (n-hexadecane) to 9.94 x 10-'cm2/s (n-hexane). The activation energy for diffusion varied from 14 kJ/mol (n-hexane) to 27 kJ/mol (n-hexadecane). Heat of sorption ranged from -1.4 kJ/mol for nheptane to 2.0 kJ/mol for n-hexadecane. The sorption/swelling results are discussed in terms of first and second order kinetic equations. The molar mass between chain-entanglement-crosslinks was estimated from swelling data. The experimental and calculated results showed a systematic dependence on the increasing size of the alkanes. None of the solvents showed any degradative effects on the polymer.

The results of the sorption and diffusion of aldehydes and ketones into structurally different elastomers such as ethylene propylene diene terpolymer, styrene butadiene rubber, nitrile butadiene rubber, neoprene and natural rubber are described in the temperature interval of 25‐60°C. From these data, the Arrhenius parameters for the processes of diffusion and permeation are determined. The activation parameters for the diffusion of ketones range from 10.29 to 49.62 kJ/mol and for aldehydes, from 13.18 to 50.42 kJ/mol; these values fall in the range expected for rubbery polymers well above their glass transition temperatures. Transport data are affected by the nature of the interacting solvent molecule rather than its size and also by the structural variations of the elastomers. For all the solvents, the polymers remained intact; however, natural rubber in the presence of benzaldehyde showed degradative reactions at higher temperatures. Volumetric expansions of the elastomers have been measured from the dimensional response in the presence of aggressive solvents.

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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.