Advances in Polyimide Membranes for Gas Separation: Synthesis, Modification, and Application

Area of Science:

• Materials Science
• Chemical Engineering
• Polymer Science

Background:

• Membrane technology is crucial for efficient gas separation, with polymer membranes dominating the market.
• Polyimide (PI) membranes are favored for their excellent performance, thermal, and chemical stability.
• Limitations of traditional PI membranes include low gas permeability and poor plasticization resistance, hindering industrial adoption.

Purpose of the Study:

• To review monomer structures, synthesis, and fabrication methods for polyimide-based membranes.
• To summarize modification strategies for improving polyimide membrane performance.
• To discuss challenges and future prospects for polyimide membranes in gas separation.

Main Methods:

• Introduction to polyimide synthesis, including solution-based and solid-state thermal condensation.
• Overview of representative polyimide-based membrane preparation techniques.
• Summary of modification strategies: thermal rearrangement, cross-linking, and physical blending.

Main Results:

• Polyimide membranes show high potential for gas separation applications.
• Modification strategies effectively address issues of low permeability and plasticization.
• Improved membranes enhance cost-effectiveness and broaden industrial applicability.

Conclusions:

• Further improvements in polyimide membrane performance and cost-effectiveness are essential.
• Strategic modifications and fabrication methods are key to overcoming current limitations.
• The review highlights ongoing challenges and future directions for advanced polyimide gas separation membranes.