【作者】 刘岩；

【导师】 蹇锡高；

【作者基本信息】 大连理工大学 ， 高分子材料， 2008， 硕士

【摘要】 杂萘联苯聚醚砜（PPES）是本组研发的一类新型高性能工程塑料,玻璃化转变温度达305℃,耐高温可溶解,并具有良好的成膜性能、机械性能和化学稳定性能;经过磺化改性的杂萘联苯聚醚砜（SPPES）不仅成为了荷电材料,而且改善了其亲水性,是制备耐高温、高性能纳滤膜的优良材料。在本研究组前期研究基础上,本文选择磺化度（D.S.）为0.87的SPPES作为复合膜涂层材料,以PPESK超滤膜为基膜,制备耐高温高效复合纳滤膜,重点研究复合膜涂层浸涂稀溶液配方及制备工艺对复合膜结构性能的影响。通过实验确定SPPES的最佳浓度为6%,根据溶解度参数计算和实验结果显示乙二醇甲醚和丙酮混合溶剂是SPPES浸涂稀溶液的理想溶剂。PEG200是理想的有机小分子添加剂,其最佳添加量在10%左右;LiCl作为理想的无机添加剂,其添加量控制在1%以内为宜;添加5%非质子极性溶剂DMAc,可同时提高复合膜的脱盐率和水通量;以丙三醇作为交联剂制得的SPPES复合膜的性能较优,交联剂丙三醇的最佳添加量为30%。复合膜在100℃下经30min热处理,对Na₂SO₄水溶液的脱盐率为96%,相应的水通量为73 L/（m²h）。利用衰减全反射红外谱图研究了SPPES复合膜的表面化学结构,利用非平衡热力学模型及静电位阻模型（ES模型）计算了SPPES纳滤膜的膜孔结构参数。考察了SPPES复合纳滤膜对不同无机盐的分离性能,其对无机盐的脱除顺序为Na₂SO₄＞MgSO₄＞NaCl＞MgCl₂,这是典型的荷负电纳滤膜的分离特性。SPPES复合膜具有良好的涂层稳定性,复合膜在沸水中30min,性能基本不变;复合膜水通量随操作压力的提高呈现线性上升的趋势,脱盐率在低压时随压力升高而增大,超过1.0Mpa后趋于稳定;复合膜具有良好的耐压密性,常温运行150min,其压密斜率为0.35;将SPPES复合膜在50mg·L^-1的H₂O₂水溶液中连续浸泡6天后测试,其脱盐率仅下降3%,说明复合膜具有良好的抗氧化能力;SPPES复合膜可在高温下运行,当操作温度由20℃升高到100℃时,其水通量增幅达到4倍多,而脱除率基本不变。综上,SPPES复合纳滤膜是一种综合性能优良的耐高温、高效分离膜。更多还原

【Abstract】 Poly（phthalazinone ether sulfone）（PPES）is an excellent engineering plastic with high-glass transition temperature（305℃）,good solubility,hydrophilicity,chemical resistance and 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 preparing good performance and heat resistance nanofiltration membrane.Based on our team previous research,SPPES（D.S.= 0.87）is chose as coating material of composite membrane,by which and PPESK UF membrane,composite nanofiltration membrane is prepared.Studies are focused on components of coating solution and preparation technics.According to experiment results,the best concentration of SPPES of coating film is 5%.The results of solubility parameter method and observation experiment show that mixed EGME and acetone is the better solvent;PEG200 is the ideal organic additive,the quantity of which is about 10%;LiC1 is the better inorganic additive,the quantity of which is below 1%; appending of DMAc enhance the water flux and rejection rate of composite membrane.The performance of composite membrane prepared by glycerin as cross-linking reagent is enhance d obviously,the proper addition is about 30%.About thirty minutes heat-treating at 100℃, the composite membrane obtain that rejection rate is 96%and water flux is 73 L/（m²h）.The chemical structure of SPPES composite membrane surface is studied by FT-IR,the membrane pore structure parameters are calculated according to the irreversible thermodynamic model and the electrostatic and steric-hindrance（ES）model.The property of separating different inorganic salt solution is studied.The inorganic electrolytes rejection of SPPES composite membrane ranks:Na₂SO₄＞MgSO₄＞NaCl＞MgCl₂,which is typical characteristics of a negatively charged NF membrane.The water flux has linear increasing trend with pressure increase and the rejection rate tend to be stable when the pressure reaches up to 1.0 Mpa.The composite membrane has excellent pressure resistance.The composite membrane could hold stable membrane separation performance when it was in the 50mg·L ^-1H₂O₂ solution.When the operating temperature is improved from 20℃to 100℃,the water flux enhances more than 4 times and rejection rate decreases a little,which show that SPPES composite membrane has outstanding heat resistance.According to results above,SPPES composite nanofiltration membrane is a kind of excellent performance and heat-resistance composite membrane.更多还原