AN ASSESSMENT OF CHEMICAL COMPATIBILITY OF BROMOBUTYL RUBBER, CHLOROSULFONATED POLYETHYLENE AND EPICHLOROHYDRIN MEMBRANES IN THE PRESENCE OF SOME HAZARDOUS ORGANIC LIQUIDS

The present study addresses the currently available polymeric material s which are possibly used as liner materials in waste chemical ponds a gainst hazardous organic liquids. To assess the chemical compatibility , bromobutyl rubber (BIIR), chlorosulfonated polyethylene and epichlor ohydrin (ECO) are selected for exposure to chloroalkanes and non-chlor inated liquids. These solvents come under the category of hazardous li quids and protection from their contamination to ground water and othe r aquatics is an important hygienic requirement. One of the possible m eans of studying the chemical compatibility of the liner membranes aga inst such liquids is to investigate their transport characteristics in to the membrane matrices. Thus, results of sorption and diffusion of t he above-mentioned systems in the temperature interval 25-60-degrees-C are presented using the sorption gravimetric technique. These results are analyzed by using the Fickian equation. The dependence of transpo rt coefficients on the size and shape of the liquid molecules is discu ssed. Transport results are greatly influenced by the type of the poly mer-solvent interactions in addition to the size of the liquid molecul es. The Arrhenius activation parameters are estimated from a temperatu re dependence of sorption, diffusion and permeation coefficients. Enth alpy and entropy of sorption for the polymer-solvent systems have also been studied. Computed parameters and experimental results are used t o discuss the transport mechanism in terms of the type and nature of t he polymer membranes and the solvent molecules. Volume dilation of the polymers in the presence of the chosen liquid media has been measured . BIIR and ECO membranes appeared to be reactive toward tetrahydrofura n at 60-degrees-C.