2, Arizona State University, Tempe, Arizona, United States
Current hazmat suits consist of continuous barrier of materials such as butyl rubber, which passively block penetration of majority of hazardous chemicals. A downside of this system is that it also prevents evaporative cooling, which is the body’s natural thermal regulation process. To address this issue, we have developed an adaptive, “selectively breathable” composite fabric of cotton coated with poly(N,N-butylphenylacrylamide). These polymeric fabrics do not respond to water vapor, which allows for perspiration and regulation of the body temperature. However, when the fabrics come in contact with a range of target chemicals, the polymer coating swells and closes the fabric pores. Here we explore different coating mechanisms both computationally using finite element model and experimentally by imaging the aerosol droplet-polymer interactions. The dynamic swelling characteristics of the polymer, based on a validated finite element model, have been utilized to characterize the fabric in terms of optimum pore size, polymer shape and cross-linking density. Our results provide estimates for optimized fabric designs and its manufacturing.