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Synthesis of Hydrogels with Antifouling Properties As Membranes for Water Purification
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Pervaporation Polyurethane Membranes Based on Hyperbranched Organoboron Polyols
Ilsiya M Davletbaeva1, Oleg O Sazonov1, Sergey E Dulmaev1
1Technology of Synthetic Rubber Department, Kazan National Research Technological University, 68 Karl Marx str., Kazan 420015, Russia.
Membranes
|December 23, 2022
Summary
Modified aminoethers of boric acid (AEBA) significantly enhance polyurethane membrane performance. These modified membranes show threefold increased vapor permeability and improved pervaporative dehydration of isopropanol.
Area of Science:
- Polymer Science
- Membrane Technology
Background:
- Aminoethers of boric acid (AEBA) are used to create polyurethane membranes.
- The structure of AEBA can be modified using bulk adducts (EM) derived from diphenylol propane diglycidyl ether and ethanolamine.
Purpose of the Study:
- To investigate the effect of EM modification on AEBA structure and properties.
- To evaluate the performance of resulting polyurethane membranes for vapor permeability and pervaporative applications.
Main Methods:
- Synthesis of modified AEBA (AEBA-EM) using diphenylol propane diglycidyl ether and ethanolamine.
- Characterization of AEBA and AEBA-EM particle size and viscosity.
- Fabrication and testing of polyurethane membranes based on AEBA and AEBA-EM for vapor permeability and pervaporative dehydration.
Main Results:
- EM modification significantly reduces the particle size and viscosity of AEBA by disrupting associative interactions.
- Polyurethane membranes incorporating AEBA-EM exhibit a threefold increase in vapor permeability compared to unmodified AEBA membranes.
- Enhanced vapor permeability is attributed to reduced cluster size and looser packing, creating hydrophilic channels for water transport.
- Pervaporative dehydration of isopropanol also shows a multiple increase in permeability coefficients.
Conclusions:
- Modification of AEBA with EM is an effective strategy to enhance the performance of polyurethane membranes.
- The structural changes induced by EM lead to significantly improved vapor and pervaporative transport properties.
- These findings suggest potential for advanced membrane applications in separation and dehydration processes.
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