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聚砜超滤膜的表面改性 总被引:8,自引:1,他引:8
本文用亲水性高分子,表面活性剂及丙烯酸化学反应对聚砜超滤膜进行表面改性,实验结果表明:丙烯酸化学改性效果最佳,可以同时提高膜通量,截留率及膜的抗污染性能。 相似文献
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通过采用聚砜、复合增韧剂对酚醛模塑料的界面进行改性,成功地制得了一种耐油型酚醛模塑料。分别在200℃和170℃的滑油中浸24h和100h,测其力学性能和电绝缘性能,除垂直纤维方向的压缩强度外,各项性能保持率均达95%以上。采用SEM等手段对改性模塑料进行研究和分析,并同国外同类材料进行比较分析,发现聚砜、复合增韧剂改性酚醛模塑料具有优异的力学性能、电绝缘性能和耐滑油性能,是国防用理想材料。 相似文献
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Nor Azah Yusof Nor Dyana Zakaria Nor Amirah Mohd Maamor Abdul Halim Abdullah Md. Jelas Haron 《International journal of molecular sciences》2013,14(2):3993-4004
Molecularly imprinted polymers (MIPs) were prepared by bulk polymerization in acetonitrile using 2,4-dinitrophenol, acrylamide, ethylene glycol dimethacrylate, and benzoyl peroxide, as the template, functional monomer, cross-linker, and initiator, respectively. The MIP membrane was prepared by hybridization of MIP particles with cellulose acetate (CA) and polystyrene (PS) after being ground and sieved. The prepared MIP membrane was characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. The parameters studied for the removal of 2,4-dinitrophenol included the effect of pH, sorption kinetics, and the selectivity of the MIP membrane. Maximum sorption of 2,4-nitrophenol by the fabricated CA membrane with MIP (CA-MIP) and the PS membrane with MIP (PS-MIP) was observed at pH 7.0 and pH 5.0, respectively. The sorption of 2,4-dinitrophenol by CA-MIP and PS-MIP followed a pseudo–second-order kinetic model. For a selectivity study, 2,4-dichlorophenol, 3-chlorophenol, and phenol were selected as potential interferences. The sorption capability of CA-MIP and PS-MIP towards 2,4-dinitrophenol was observed to be higher than that of 2,4-dichlorophenol, 3-chlorophenol, or phenol. 相似文献
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Mehmood Mian Farrukh Paula Bosch Mattia Giagnorio Alberto Tiraferri Marco Sangermano 《Polymer International》2017,66(1):64-69
A systematic investigation of the effect of the presence of acrylate resin on polysulfone‐based membranes was performed with the aim of obtaining chemically stable crosslinked membranes without affecting their flux performances. The membranes were prepared via UV curing of the polymer dope followed by a non‐solvent‐induced phase separation process. Two different acrylic monomers were investigated and their amount was varied in the polymer dope, to study the influence of concentration on final results. High crosslinking degrees were achieved by irradiating the solution for one minute. Morphological investigations of the active surface and of the cross‐sections of the fabricated membranes showed that the typical porosity of ultrafiltration membranes was obtained starting from solutions containing a low amount of crosslinker (10 wt%), which is consistent with the water flux values which were comparable to that of the pristine polysulfone membrane. High concentrations of crosslinker resin in the initial polymer dope produced denser membranes with lower permeability. High rejection of 27 nm particles (>90%) was measured for all samples having measurable flux. The addition of the crosslinker allowed one to obtain stability in various solvents without affecting the flux and rejection performance of the porous membranes. © 2016 Society of Chemical Industry 相似文献
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《Polymer-Plastics Technology and Engineering》2013,52(3):275-281
Studies have been carried out on the chloromethylation reaction of polystyrene and polysulfone for obtaining soluble chloromethylated polymers with a high degree of substitution. The mixture of paraformaldehyde/chlorotrimethylsilane as the chloromethylation agent, stannic tetrachloride as the catalyst, and chloroform as the solvent was used for the chloromethylation reaction of these polymers. The degree of substitution and the chlorine content depend on the [SnCl4]/[polymer structural unit], [Me3SiCl]/ [polymer structural unit] molar ratios and the reaction time. 相似文献
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A novel phthalimidomethyl polysulfone (PIPSf)/polysulfone(PSf) blend affinity membrane was prepared and applied for the removal of p‐nitrophenol from aqueous solutions. In this work, the chloromethylated polysulfone (CMPSf) was used to introduce phthalimido groups onto the polysulfone backbone by Gabriel reaction. The polymers can be easy to phthalimidomethylate to different degrees by control of the reaction temperature and time. Structures of the resulting polymers were confirmed by FT‐IR. The obtained polymers showed good solubility in dimethylformamide, dimethylacetamide and formed the affinity membrane blending with polysulfone at different blend compositions by the phase‐inversion method. Thus the properties of films were characterized with respect to water flux, pore size, and porosity. The surface and cross‐sectional views of the blend membranes were analyzed by scanning electron microscopy (SEM). The research on treatment of removal p‐nitrophenol was carried out by affinity membrane process. The adsorption capacity increased with increasing the initial concentration of p‐nitrophenol in aqueous solution, and the adsorption isotherm fitted the Freundlichmodel well. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献