Synthesis And Water Vapor Permeability Of Sulfonated Heterocyclic Poly (Aryl Ether)s Containing Pendant Phenyl Groups

Gas membrane separation technology is widely used in all walks of life because of its environmentally friendly, high separation efficiency and low energy consumption. And it starts to be applied in dehumidifying technology with the growth requirements of dehumidification. As the core of membrane technology in dehumidification, the membrane material should have good hydrophilicity. As an important part of membrane materials, polymer materials are highly valuable for higher selectivity. Poly(aryl ether) is one of the polymer gas separation materials with good comprehensive performance, but its hydrophilic performance is not good. The hydrophilicity of the polymer is improved by structural modification, which is a commonly used method, and then the materials are applied in dehumidification membranes.In this thesis, heterocyclic poly(aryl ether sulfone)s containing pendant phenyl groups (PPES-Ps) and heterocyclic poly(aryl ether ketone)s containing pendant phenyl groups(PPEK-Ps) have been synthesized successfully. The polymers were synthesized from 4-(4-hydroxyphenyl)-2,3-phthalazin-1-ketone(DHPZ),4,4’-dichlorodiphenyl sulfone, 4,4-difluorobenzophenone,4-(3-phenyl-4-hydroxyphenyl)-2,3-phthalazin-l-ketone(DHPZ-P) via polycondensation with different proportions of DHPZ and DHPZ-P. FT-IR and’H-NMR were used to confirm the structures of the as-prepared polymers, the test results showed that expected structures has been prepared successfully.Sulfonated heterocyclic poly(aryl ether sulfone)s containing pendant phenyl groups(SPPES-Ps) and sulfonated heterocyclic poly(aryl ether ketone)s containing pendant phenyl groups(SPPEK-Ps) were prepared with concentrated sulfuric acid(98%) as solvent and sulfonating agent. FT-IR and’H-NMR were used to characterize the structures of SPPES-Ps and SPPEK-Ps. The TGA and intrinsic viscosity results indicated that the resulting polymers had good thermal stabilities and high molecular weight. SPPES-Ps and SPPEK-Ps membranes were prepared through the solution casting method with NMP as solvent. With the increasing of IEC, both swelling ratio and water uptake of the membranes increased. The dynamic contact angle testing results showed that the membranes were hydrophilic. The water vapor permeability tests indicated that the WVP enhanced with the increasing of IEC and temperature. Furthermore, the relation of temperature and WVP was in line with the Arrhenius equation, which confirmed that the water vapor permeation rate had temperature dependence.The performances of SPPES-Ps membranes were contrasted with SPPEK-Ps membranes with similar IEC values, and the membranes also were compared with SPPEK membranes without pedant phenyl group. The results indicated that SPPES-Ps had better solubility in polar aprotic solvent compared to SPPEK-Ps. Within the same interval, the values of dynamic contact angle of SPPES-Ps were lower. And the values of SPPEKs were the highest, which showed that its hydrophilicity was lower than those of sulfonated heterocyclic poly(aryl ether)s containing pendant phenyl groups. The values of the water vapor permeability of SPPES-Ps membranes were higher than those of SPPEK-Ps membranes. And compared to SPPEKs, SPPEK-Ps with pendant phenyl groups showed higher hydrophilicity and water vapor permeability.