Mechanical degradation of filter polymer materials: Polyphenylene sulfide

Polyphenylene sulfide (PPS) is known as a material resistant to high temperature and chemicals; however, there are arguments on the durability of PPS non-woven fabrics to chemicals, such as nitric acid (HNO₃), sulfuric acid (H₂SO₄), and hydrochloric acid (HCl). Therefore, this work aims at investigating the degradation of PPS non-woven fabrics in HNO₃, H₂SO₄ and HCl, and at confirming acid durability of PPS non-woven fabrics. In addition, this paper also studies the interaction among these three acids by measuring the retention of strength in binary or tertiary mixtures of these three acids. A discussion has been made on the acceleration/retardation of PPS degradation by the interactive effects, and also on the chemistry related to the degradation by these acids. Furthermore, there is a linear relationship between the nitric acid concentration and the proportion of carbon in the remaining PPS structures after 100 h of acid exposure. Also, this proportion of carbon is a good indicator of the retained strength in PPS fabrics.