Sorption and Diffusion Profiles of Monocyclic Aromatic Liquids into Polymeric Blends of Ethylene-Propylene Random Copolymer and Isotactic Polypropylene∗

∗ Presented at the Indo-French Workshop on Separations by Adsorption and Membrane Processes held at Nancy, France, April 10–23, 1994, under the auspices of the Indo-French Center for the Promotion of Advanced Research, New Delhi, India. This project has been funded in part with federal funds as part of the program of the Gulf Coast Hazardous Research Center, which is supported under Cooperative Agreement R815197 with the United States Environmental Protection Agency; and in part with funds from the State of Texas as part of the program of the Texas Hazardous Waste Research Center. The contents do not necessarily reflect the views and policies of the U.S. EPA or the State of Texas, nor does the mention of tradenanies or commercial products constitute endorsement or recommendation for use.

Abstract

Molecular transport of monocyclic aromatics into polymeric blends of ethylene-propylene random copolymer and isotactic polypropylene is investigated in the temperature interval 25°-70°C. For all liquids, the penetrant transport rate, equilibrium penetrant uptake, and degree of penetrant overshoot are influenced by the type of the penetrant and the experimental temperature. Sorption-desorption-resorption-redesorption (S-D-RS-RD) experiments have been performed to determine the true equilibrium sorption and diffusion coefficients. These S-D-RS-RD experiments are a convenient method of determining the continuous weight loss during long-term solvent exposure, a phenomenon associated with the release of residuals. The molar mass between crosslinks of the polymer, the kinetic rate constants, and the activation parameters for diffusion, permeation, and sorption are obtained. Transport coefficients and the activation parameters are affected by the type and size of the penetrant molecules. The sorption kinetic results indicate that the transport is of the anomalous type.

∗ Presented at the Indo-French Workshop on Separations by Adsorption and Membrane Processes held at Nancy, France, April 10–23, 1994, under the auspices of the Indo-French Center for the Promotion of Advanced Research, New Delhi, India. This project has been funded in part with federal funds as part of the program of the Gulf Coast Hazardous Research Center, which is supported under Cooperative Agreement R815197 with the United States Environmental Protection Agency; and in part with funds from the State of Texas as part of the program of the Texas Hazardous Waste Research Center. The contents do not necessarily reflect the views and policies of the U.S. EPA or the State of Texas, nor does the mention of tradenanies or commercial products constitute endorsement or recommendation for use.

Key Words:

• Aromatics
• Diffusion
• Fickian
• Santoprene

Notes

∗ Presented at the Indo-French Workshop on Separations by Adsorption and Membrane Processes held at Nancy, France, April 10–23, 1994, under the auspices of the Indo-French Center for the Promotion of Advanced Research, New Delhi, India. This project has been funded in part with federal funds as part of the program of the Gulf Coast Hazardous Research Center, which is supported under Cooperative Agreement R815197 with the United States Environmental Protection Agency; and in part with funds from the State of Texas as part of the program of the Texas Hazardous Waste Research Center. The contents do not necessarily reflect the views and policies of the U.S. EPA or the State of Texas, nor does the mention of tradenanies or commercial products constitute endorsement or recommendation for use.