Improving aging resistance of PIM‐1 thin films by nano‐TiO2 filler used for robust solvent permeation. Issue 15 (31st January 2022)

• Record Type: Journal Article
• Authors: Huang, Zhaolai; Li, Jiaqi; Zhang, Mengxiao; Feng, Weilin; Fang, Chuanjie; Zhu, Liping
• Is Part Of: Journal of polymer science. Volume 60:Issue 15(2022)
• Page Start: 2298
• Page End: 2308
• Publication Date: 2022-01-31
• Subjects: aging resistance -- membranes -- polymers of intrinsic microporosity -- robust solvent permeation; Polymers -- Periodicals; Polymerization -- Periodicals; Polymerization; Polymers; Periodicals; 547.7
• DOI: 10.1002/pol.20210931
• Languages: English
• ISSNs: 2642-4150

Abstract

Abstract: Polymers of intrinsic microporosity (PIMs) are promising materials for membrane separation because their special rigid and contorted structures contribute to high permeability. However, their chain rearrangement to fill excessive free volume makes the permeability stability a tough challenge. In this work, we report on a new use of rutile nano‐TiO2 to mitigate the physical aging of PIM‐1 (a typical PIM) nanofilms for stable permeability by mixing matrix. It was shown that the PIM‐1 membrane incorporated with nano‐TiO2 displayed remarkably higher aging resistance with a lower swelling degree in long‐term ethanol soaking, having more stable ethanol permeance with only a 5% decrease after 35 days, lower than 25% of the pure one. The mechanism of anti‐aging was revealed by molecular simulation, thermal, tensile mechanical, and dynamic mechanical analysis. It was found that nano‐TiO2 had good compatibility with PIM‐1 due to strong coordination interaction, making its uniform dispersion in polymer. Additional solvent permeation channels were also created to increase solvent permeance without compromising solute rejection. Due to the reliable interaction of nano‐TiO2, which makes particles serve as physical crosslinking points, the movement of PIM‐1 chains was limited partially to mitigate aging, enabling PIM‐1‐based membranes to have robust solvent permeation. Abstract :