Boosting m-aramids performance with p-oriented aromatic amide side chains

Abstract

This study aimed to enhance the mechanical properties of m-aramids by incorporating varying percentages of p-aramid side chains through copolymerization while ensuring solubility for practical applications. The mechanical performance of the resulting copolymers was compared with the commercial m-aramid, MPIA (poly(m-phenylene terephthalamide)). Notably, even with a 20% incorporation of p-aramid side chains, there was a substantial increase of 48% in Young’s modulus and 7% in tensile strength compared to MPIA. Additionally, the nitro group capping the p-aramid side chains demonstrated significant efficacy in enhancing the mechanical performance of the materials upon exposure to hydrogen. Specifically, there was an increase of more than 11% in Young’s modulus upon initial contact with hydrogen. This finding suggests potential applications in protective coatings for stainless steel used in high-pressure hydrogen storage environments. In such applications, exposure to hydrogen can accelerate embrittlement and limit operational lifespan, and coating with these materials can mitigate embrittlement and improve operational lifespan.