Organophosphorus Polyurethane Ionomers as Water Vapor Permeable and Pervaporation Membranes.

Organophosphorus polyurethane ionomers (AEPA-PU) based on aminoethers of ortho-phosphoric acid (AEPA) were obtained and studied as pervaporation membrane materials for separating isopropanol/water mixtures. The regularities of the change in the water vapor permeability of AEPA-PU were also investigated. It has been established that an increase of solute content in the composition of the urethane-forming system and the content of ionogenic groups in AEPA leads to a noticeable increase in the vapor permeability of the resulting film materials. An increase in water vapor permeability values is accompanied by a significant increase in the pervaporation characteristics of AEPU-PU. It was shown that the conditions promoting clustering of phosphate anions cause an increase in the values of the vapor permeability coefficient of AEPA-PU obtained using polyoxypropylene glycol. However, the hydrophobicity of the polypropylene glycol surrounding the clusters makes it difficult for water to move through the polymer matrix. Due to the hydrophilicity of polyoxyethylene glycol, the highest values of water vapor permeability and pervaporation characteristics are achieved for AEPA-PU synthesized using PEG.

Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation.

Amphiphilic poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate cross-linked block copolymers based on triblock copolymers of propylene and ethylene oxides with terminal potassium-alcoholate groups (PPEG), octamethylcyclotetrasiloxane (D4) and 2,4-toluene diisocyanate (TDI) were synthesized and investigated. In the first stage of the polymerization process, a multiblock copolymer (MBC) was previously synthesized by polyaddition of D4 to PPEG. The usage of the amphiphilic branched silica derivatives associated with oligomeric medium (ASiP) leads to the structuring of block copolymers via the transetherification reaction of the terminal silanol groups of MBC with ASiP. The molar ratio of PPEG, D4, and TDI, where the polymer chains are packed in the "core-shell" supramolecular structure with microphase separation of the polyoxyethylene, polyoxypropylene and polydimethylsiloxane segments as the shell, was established. Polyisocyanurates build the "core" of the described macromolecular structure. The obtained polymers were studied as membrane materials for the separation of gas mixtures CO2/CH4 and CO2/N2. It was found that obtained polymers are promising as highly selective and productive membrane materials for the separation of gas mixtures containing CO2, CH4 and N2.