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<正>Poly(vinylidenefluoride-hexafluoropropylene)(PVDF-HFP) nanofiber membranes with improved hydrophilicity and protein fouling resistance via surface graft copolymerization of hydrophilic monomers were prepared.The surface modification involves atmospheric pressure glow discharge plasma(APGDP) pretreatment followed by graft copolymerization of poly(ethylene glycol) methyl ether methacrylate(PEGMA).The success of the graft modification with PEGMA on the PVDF-HFP fibrous membrane is ascertained by X-ray photoelectron spectroscopy(XPS) and attenuated total reflectance Fourier transform infrared measurements(ATR-FTIR).The hydrophilic property of the nanofiber membranes is assessed by water contact angle measurements.The results show that the PEGMA grafted PVDF-HFP nanofiber membrane has a water contact angle of 0°compared with the pristine value of 132°.The protein adsorption was effectively reduced after PEGMA grafting on the PVDF-HFP nanofiber membrane surface.The PEGMA polymer grafting density on the PVDF-HFP membrane surface is measured by the gravimetric method,and the filtration performance is characterized by the measurement of water flux.The results indicate that the water flux of the grafted PVDF-HFP fibrous membrane increases significantly with the increase of the PEGMA grafting density. 相似文献
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<正>Zein/chitosan composite fibrous membranes were fabricated from aqueous ethanol solutions by electrospinning. Poly(vinyl pyrrolidone)(PVP) was introduced to facilitate the electrospinning process of zein/chitosan composites.The asspun zein/chitosan/PVP composite fibrous membranes were characterized by scanning electron microscopy(SEM) and tensile tests.SEM images indicated that increasing zein and PVP concentrations led to an increase in average diameters of the composite fibers.In order to improve stability in wet stage and mechanical properties,the composite fibrous membranes were crosslinked by hexamethylene diisocyanate(HDI).The crosslinked composite fibrous membranes showed slight morphological change after immersion in water for 24 h.Mechanical tests revealed that tensile strength and elongation at break of the composite fibrous membranes were increased after crosslinking,whereas Young's modulus was decreased. 相似文献
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李新松 《中国高校科技与产业化》2004,(5):77-78
教育部科技发展中心的统计资料显示,从1998~2003年,我国高校科技产业的销售收入、利润总额、上缴税金、上缴学校费用均呈现大幅度增长趋势。5年间,高校科技企业销售年均增长为25.3%,为全国平均水平的三倍。蓬勃发展的高校校办产业令人欢欣鼓舞,但如何才能保持这种蓬勃发展的态势呢? 相似文献
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静电纺丝是通过对聚合物溶液或熔体施加外电场制造纳米纤维的有效方法.电纺过程中,在静电力作用下聚合物射流快速鞭动,形成的纳米纤维无规堆砌,得到无纺布状的无规纳米纤维膜.这种纳米纤维膜具有极大的比表面积,已用于超高效过滤,在刨伤修复、组织工程、水处理等领域有广泛的应用前景.为了进一步拓展纳米纤维在纤维工业、纺织品、微制造等领域的应用,电纺纳米纤维的取向和连续长纱的制备研究受到科学家的重视,文献报道了多种纳米纤维取向方法.本文分析了纳米纤维膜无规堆砌结构的形成机理,总结了纳米纤维取向研究和连续长纱制备研究进展,特别介绍了基于静电作用分析提出的共轭电纺方法,讨论了取向纳米纤维的应用以及纳米纤维未来的研究方向. 相似文献
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壳聚糖多孔支架的制备与生物学性质 总被引:5,自引:0,他引:5
用一种蛋白改性壳聚糖,通过冷冻干燥方法制备三维多孔支架,对支架材料的细胞毒性、贴壁率和细胞增殖等生物学特性进行评价.结果显示,采用-20,-70,-196 ℃不同温度预冻后冻干,可以制成孔结构不同的支架材料.通过冻干法制备的蛋白改性壳聚糖多孔支架对细胞没有毒性,L929细胞和人成纤维细胞可以在支架表面和内部正常生长和增殖,角质细胞在材料表面可以正常老化、角质化. 相似文献
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A simple method is adopted to grow ZnO nanofibers laterally among the patterned seeds designed in advance on silicon substrate. The preparation of seed lattices is carried out by lithographing the metal zinc film evaporated on the substrate. A layer of aluminum is covered on the zinc layer to prevent the ZnO nanorods vertically growing on the top surface. After oxidation, the patterned ZnO/Al2O3 spots are formed at the sites for the horizontal growth of ZnO nanofibers by the vapor phase transportation (VPT) method using the zinc powders as source material. 相似文献