Breathability and Selectivity of Selected Materials for Protective Clothing

摘要

A series of materials was evaluated for its potential use as breathable (high water transport) barriers (low chemical agent transport) for military and civilian protective clothing apparel. The vapor transmission rates and effective permeabilities of water and dimethyl methyl phosphonate (DMMP) simulant for chemical agent (Sarin) through commercial and experimental polymeric membranes were measured using a modified American Society for Testing and Materials Method E-96-95. A variety of different materials from different companies was examined; unfortunately, some cannot be named due to proprietary restrictions. Materials examined included expanded PTFE, Nafion 117, sulfonated polystyrene-polyeth ylene-ran-polybutylene- polystyrene, sulfonated polystyrenepolyisobu tylene-polystyrene, as well as four experimental and commercial membranes (A, B, C, and D). Results demonstrated that laminated membrane A had the highest breathability (effective permeability of water vapor) ; however, an experimental laminated material C possessed the highest selectivity with sufficient breathability, where selectivity was defined as the ratio of water permeability to DMMP permeability. Based on the results from this study, material C presented the greatest potential for a breathable barrier material for a chemical protective clothing application.