Student Research: Joshua Porton
MS, , 1999
Faculty Advisor: Michael S Morgan
Comparison of the Permeation Rates of Selected Glove Materials by Mixtures of Methyl Ethyl Ketone and Toluene at Skin and Room Temperature
Dermal exposure is potentially high among industrial workers. Chemical protective clothing (CPC) is meant to guard the skin against exposure but CPC is not able to protect against all chemicals in all situations. Previous studies have dealt with the permeation of CPC by pure solvents, and more recent studies included solvent mixtures, but most of these studies have used room temperature instead of closer to skin temperature. By using room instead of skin temperature, the authors of these studies are underestimating the permeation rates of the solvents through the CPC because the values of rate constants have been shown to increase exponentially with increasing temperature.
Five solvent mixtures were tested. A piece from the glove was exposed to the challenge solution and the concentration permeating through the glove material was monitored against time. For each run, the permeation rate and degree of swelling were calculated. The increase in temperature from an average of 22.7 degrees C in a previous study to approximately 34 degrees C caused significant increases in steady-state permeation rates for the majority of the mixture/glove combinations. Concerning the interaction between toluene and methyl ethyl ketone (2-Butanone), the same characteristics were observed as in the previous study by Georgoulis (1994) used as a comparison.
Temperature does appear to have an effect on the permeation behavior of MEK and toluene through both natural rubber and nitrile rubber.