| Poly(phthalazinone ether sulfone)(PPES) is an excellent engineering plastic withhigh-glass transition temperature(305℃), good solubility, hydrophilicity, chemical resistanceand mechanical properties. Sulfonated modified not only let PPES become a charged material,but also improve hydrophilic properties of it, so SPPES is an excellent material for preparinghigh flux and heat resistance nanofiltration membrane.We choose solvents for SPPES by the solubility parameter method and prepare thin-filmcomposite membrane(TFC) successfully with SPPES as coating material. The results showthat the composite membrane present excellent properties when solvent is ethoxy + THFmixture (volume ratio 1:1), the polymer concentration is 5％, sulfonation degree is 0.60,heat-treating temperature is 60℃, heat-treating time is 30 minutes and two times spread. Thecomposite membrane prepared from PSfultrafiltration membrane exhibites higher water fluxand lower thermostable temperature than the composite membrane prepared from PPESK orPPES. Proper addition of glycerin in thin film solution can enhance water flux combined withrejection rate; The water flux of TFC membrane increase and the rejection rate no changewith methanal or anhydrous ethanol as additive in thin film solution. The water flux of thecomposite membrane prepared with 2％LiCl as additive in thin film solution is 20 L/(m2h),1000mg/L Na2SO4 solute rejection rate is 93％when operation pressure is 0.5MPa. The waterflux increase and rejection rate decrease with DMF as polar aprotic solvents in thin filmsolution, the rejection rate increase and water flux decrease with DMSO as polar aproticsolvents in thin film solution.The physicochemical characteristics of SPPES/PPESK composite membranes and theinfluence of operation condition on properties of TFC membrane are also studied. The resultsshows that the composite membrane has excellent pressure resistance, chlorine resistance,acid and alkaline resistance and outstanding heat resistance, could keep properties in 100℃condition. The water flux enhances more than 3 times and rejection rate decreases below 13％when solution temperature rises from 20℃to 100℃. The flux has linear increasing trendwith pressure increase and the rejection rate increase slightly with pressure increase and tendto be stable when the pressure reaches up to 0.8MPa. The rejection rate to inorganic saltsolution of SPPES/PPESK from high to low in sequence is Na2SO4＞NaCl≥MgSO4＞MgCl2.The water flux increase with solution concentration increase, the rejection rate decrease andtend to be stable when the concentration reaches up to 1500mg/L. The molecular weightcutoff of composite membrane are 595.8, 603 and 758.6 (PEG molecular weight)respectively with different methods for value assignment, it is 2nm when convert to membrane pore size, this size belongs to the scope of nanofiltration. The water flux andrejection rate are both increase when composite membrane in going from SPPES-H form toSPPES-Na form. The water flux increase and rejection rate decrease when compositemembrane going from SPPES-H form to SPPES-Mg form. The properties of SPPES/PPESKcomposite membrane can be comparable to commercial nanofiltration membrane, it provesthat SPPES is an excellent thin film composite membrane material and the process forpreparation composite membrane is a feasible technology. The researches show that goodeffect is also displayed when treat industry wastewater and dyes wastewater bySPPES/PPESK composite membrane.
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