Permeation data, where available to date, cover only one style in any product line. Most unsupported glove product lines are made in several styles, generally differing in thickness. This is a report on an investigation of the effects of these differences in thickness on measured permeation properties.

Five typical industrial chemicals were tested: aniline, dimethylformamide (DMF), hexane, methyl isobutyl ketone (MIBK), and toluene. Film specimens were made in thicknesses of about 15 mils and about 25 mils from each of five unsupported glove formulations. Two of these formulations are available commercially as Edmont 29-series neoprene and Sol-Vex nitrile gloves; the other three were experimental butyl latex systems. All the tests were run in duplicate using apparatus and procedures from the ASTM Test for Resistance of Protective Clothing Materials to Permeation by Hazardous Liquid Chemicals (F 739-81). The collecting medium was a continuous stream of dry nitrogen, sampled at intervals with a gas sampling valve. The samples were passed through the analytical column of a Gow-Mac gas Chromatograph and detected by flame ionization detection (FID).

For 3 of the possible 25 combinations of chemicals and protective films, no break throughs were observed. In 5 others, the chemical did not breakthrough the film soon enough or in sufficient quantity to provide complete data on the effects of film thickness. For 10 combinations, the change in thickness had a much greater effect on breakthrough time than on permeation rate. In only 6 cases did an increase in thickness reduce the measured steady-state permeation rate, and the breakthrough time was increased for 5 of these. One case was an anomaly, since the thicker specimen had a longer breakthrough time but a higher rate measurement. Repeat tests confirmed this anomaly.

We conclude that a change in thickness is more likely to affect breakthrough time than steady-state permeation rate.