PIM-PI-1 and Poly(ethylene glycol)/Poly(propylene glycol)-Based Mechanically Robust Copolyimide Membranes with High CO2-Selectivity and an Anti-aging Property: A Joint Experimental-Computational Exploration

Iqubal Hossain; Sanggil Park; Asmaul Husna; Yeonho Kim; Hyungjun Kim; Tae-Hyun Kim

doi:10.1021/acsami.1c14034

PIM-PI-1 and Poly(ethylene glycol)/Poly(propylene glycol)-Based Mechanically Robust Copolyimide Membranes with High CO₂-Selectivity and an Anti-aging Property: A Joint Experimental-Computational Exploration

ACS Appl Mater Interfaces. 2021 Oct 27;13(42):49890-49906. doi: 10.1021/acsami.1c14034. Epub 2021 Oct 13.

Authors

Iqubal Hossain^{1

2}, Sanggil Park^{2

3}, Asmaul Husna^{1

2}, Yeonho Kim^{2

4}, Hyungjun Kim^{2

3}, Tae-Hyun Kim^{1

2}

Affiliations

¹ Organic Material Synthesis Laboratory, Department of Chemistry, Incheon National University, Incheon 22012, Republic of Korea.
² Research Institute of Basic Sciences, Incheon National University, Incheon 22012, Republic of Korea.
³ Quantum Chemistry Laboratory, Department of Chemistry, Incheon National University, Incheon 22012, Republic of Korea.
⁴ Department of Applied Chemistry, Konkuk University, Chungju 27478, Republic of Korea.

PMID: 34643079
DOI: 10.1021/acsami.1c14034

Abstract

Polymer membranes with excellent thermomechanical properties and good gas separation performance are desirable for efficient CO₂ separation. A series of copolyimide membranes are prepared for the first time using PIM-PI-1, a hard segment with high CO₂ permeability, and poly(ethylene glycol)/poly(propylene glycol) (PEG/PPG), a soft segment with high CO₂ selectivity. Two different unit polymers are combined to compensate the limitations of each polymer (e.g., the fast aging and moderate selectivity of PIM-PI-1 and the poor mechanical properties and lower permeability of PEG/PPG). The corresponding PIM-(durene-PEG/PPG) membranes exhibit an excellent combination of mechanical properties and gas separation performance compared to the typical PI-PEG-based copolymer membrane. The improved mechanical property is attributed to the unique chain threading and the reinforcement between the spiro unit of PIM and the flexible PEG/PPG at the molecular level, which has not previously been exploited for membranes. The PIM-(durene-PEG/PPG) membranes show a high CO₂ permeability of 350-669 Barrer and a high CO₂/N₂ selectivity of 33.5-40.3. The experimental results are further evaluated with theoretical results obtained from molecular simulation studies, and a very good agreement between the experimental results and simulation results is found. Moreover, the PIM-(durene-PEG/PPG) copolymer membranes display excellent anti-aging performance for up to 1 year.

Keywords: anti-aging performance; gas separation; molecular simulation; permeability versus tensile strength trade-off; rigid−soft copolyimide membrane.