Novel poly(vinylidene fluoride)/thermoplastic polyester elastomer composite membrane prepared by the electrospinning of nanofibers onto a dense membrane substrate for protective textiles

Abstract

ABSTRACTConventionally, electrospun thin‐film composite (TFC) membranes used in protective clothing are fabricated on the basis of an electrospinning substrate coated with a nonporous hydrophilic polymer layer. However, the incompatibility of common coating solvents with inertia substrate materials requires that the support material should be surface‐modified to promote the crosslinking of the dense and porous layers. In this study, we attempted to fabricate a novel TFC membrane for use in protective clothing by the one‐step deposition of poly(vinylidene fluoride) (PVDF) nanofibers onto a dense, hydrophilic thermoplastic polyester elastomer (TPEE) membrane substrate via electrospinning. The proposed approach has the advantage of no need for further surface modification of the substrate membrane. The optimized TFC membrane exhibited a better tensile strength than the dense substrate TPEE film. The testing results for the moisture resistance show that the new TFC membrane had a comparatively high water vapor transmission rate, notwithstanding that the value was slightly lower than that of the single‐layered TPEE film. Simultaneously, a resistance‐in‐series model based on Henis–Tripodi's model for explaining the water vapor permeation behavior of the TFC membrane was proposed. The moisture resistance values predicted by the analyzed model were in good agreement with these experimental data. This verified the validity of this in‐series moisture resistance model for the TFC membrane. The influence of the PVDF porosity on the water vapor permeation resistance throughout the TFC membrane was calculated and is discussed. More work is needed to establish the applicability of the new TFC membrane for lamination with nonwoven fabric to form the multilayered fabrics used in firefighters’ protective clothing. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42170.