Synthesis of Polyurethane Hydrogel and Polyurethane Thermoplastic Elastomer Composite Based Separation Membranes

Area of Science:

• Materials Science
• Polymer Chemistry
• Separation Technology

Background:

• Polyurethane (PU) based membranes are widely used in separation processes.
• Developing advanced membranes with stimuli-responsive properties is crucial for targeted applications.

Purpose of the Study:

• To synthesize and characterize novel polyurethane hydrogel and polyurethane thermoplastic elastomer composite membranes.
• To investigate the influence of incorporated functional groups and composite structure on membrane properties.
• To evaluate the performance of these membranes in selective separation, particularly for glycine, under varying environmental conditions.

Main Methods:

• Membrane preparation using the wet phase inversion method.
• Characterization of membrane morphology (SEM), chemical structure (FTIR), thermal properties (DSC), and crystallinity (XRD).
• Assessment of equilibrium swelling ratio (ESR), water flux (J), and permeation percentage (P) of glycine under different temperature and pH conditions.

Main Results:

• The prepared PU membranes displayed irregular porous structures with asymmetrical pore paths.
• FTIR confirmed the incorporation of thermal-sensitive and pH-sensitive groups into the PU network.
• DSC and XRD indicated partial disruption of the PU network structure due to the addition of polyurethane thermoplastic elastomer.
• Membrane performance showed a decrease in ESR and an increase in water flux with structural modifications.
• Glycine permeation was significantly influenced by external temperature and pH.

Conclusions:

• Successfully fabricated composite PU membranes with tailored properties.
• Demonstrated the stimuli-responsive behavior of the membranes to temperature and pH.
• Highlighted the potential of these smart membranes for selective separation of molecules like glycine.