电纺制备聚乳酸/聚醚砜复合纳米纤维膜及性能研究

采用同轴静电纺丝制备聚乳酸/聚醚砜(PLA/PES)复合纳米纤维膜,通过改变皮层溶液的挤出速率以及在芯层溶液中分别添加石墨烯（GO）、碳纳米管(MWCNTs)、埃洛石（HNTs）纳米粒子,制备了系列皮芯结构的复合纳米纤维膜。通过扫描电子显微镜、纤维强伸度仪、接触角测定仪等仪器测试表征了复合纳米纤维膜的纤维结构、拉伸强度、疏水性以及吸油倍率等性能。结果表明,制备的复合纳米纤维膜的接触角均大于130 °,表现出较好的亲油疏水性;当往芯液中添加石墨烯(GO)时,纳米纤维膜的吸油性能、拉伸性能最好,在甘油中的吸油倍率可达到67.61倍,食用油中可达到48.02倍,纵向断裂强度为62.68 MPa,横向断裂强度为43.98 MPa,横向断裂伸长率可达到697.76 %。     

密度梯度复合滤料的结构与过滤性能研究

以聚丙烯(PP)纺粘布(简称纺粘布)为支撑层、PP熔喷布(简称熔喷布)为中间滤层、静电纺聚乳酸纳米纤维布(简称电纺布)为表面滤层,制备三级密度梯度结构复合滤料(简称三级梯度滤料),以纺黏布和熔喷布制得二级密度梯度结构复合滤料(简称二级梯度滤料),借助自动滤料测试仪等研究了滤料的结构和性能。结果表明:纺粘布、熔喷布和电纺布的纤维平均直径分别为19.58,2.89,0.71μm,平均孔径分别为76.80,12.02,2.52μm;在纤维层单位面积质量相近的情况下,随着纤维平均直径变小,滤料平均孔径变小,纤维直径和滤料平均孔径的变动幅度基本一致。三级梯度滤料的平均孔径为2.12μm,孔径分布为0.89~4.40μm;与二级梯度滤料相比,三级梯度滤料孔径范围变窄,平均孔径下降了80.5%,在气体流量为32L/min时,对空气动力学质量中值直径为0.26μm的NaCl气溶胶的过滤效率达到99.2%,过滤效率提高了66.7%,三级梯度滤料综合过滤性能得到明显提升;密度梯度滤料的阻力具有加和效应,约等于各纤维层阻力之和,密度梯度滤料的过滤效率不具有加和效应,主要取决于过滤效率最高的纤维层。     

PLA微纳米纤维复合过滤非织造布的制备与性能

通过液喷侧吹纺丝方法制备了聚乳酸(PLA)微纳米纤维和PLA/聚丙烯(PP)熔喷复合过滤非织造材料,探讨了液喷工艺参数对PLA微纳米纤维直径和分布的影响,并对不同制备条件下的PLA/PP复合过滤非织造布的力学性能、透气性及过滤性能进行了测试。结果表明,在PLA溶液质量分数为7%,风压为0.3 MPa,接收距离为35 cm,挤出速率分别为15,20,25 m L/h的条件下,可获得直径分别为0.98,1.02,1.12μm的PLA微纳米纤维。当液喷侧吹时间为30 min、挤出速率为20 m L/h时,PLA/PP复合过滤非织造布的透气性下降了52.48%,而过滤阻力、断裂强度和过滤效率分别提高了22.79%,94.51%和46.84%,其综合性能得到明显改善。     

螺纹式喷头制备PAN纳米纤维及其空气过滤性能

以聚丙烯腈(PAN)为纺丝液,采用自主设计研发的螺纹式喷头静电纺丝装置制备了幅宽为600 mm的纳米纤维膜。通过扫描电镜和孔径测定仪考察了纤维形貌以及直径分布,并测试了纳米纤维膜对0.26μm氯化钠粒子的过滤性能。结果表明:纤维的平均直径为138 nm,平均孔径为1.98μm,纤维膜平均厚度为0.025 mm;PAN纳米纤维膜过滤效率为99.899%,滤阻为280.9 Pa。     

静电纺丝纤维滤材表征及其气液过滤性能

以聚丙烯腈与二甲基甲酰胺为原料配制纺丝溶液,采用静电纺丝技术制备玻璃纤维/聚丙烯腈纤维/玻璃纤维三层复合滤材,研究了纺丝溶液浓度与纺丝电压等参数对纤维形貌及尺寸的影响,分析了复合滤材的过滤性能. 结果表明,控制不同纺丝溶液浓度可得形貌不同的纤维,且溶液浓度越大纤维尺寸越大;纺丝电压对纤维形貌的影响较小,但增加纺丝电压使静电纺纤维层的孔径减小. 相比玻璃纤维滤材,复合滤材过滤效率明显提升,稳态效率最大可提升21%,最易穿透粒径效率最大可提升39%,但复合滤材孔径较小时,过程压降增加了一段跳跃阶段,纳米纤维层表面形成液膜,使复合滤材稳态压降升高.     

聚乳酸/肉桂醛复合纳米纤维膜的制备及表征

采用水溶液饱和法制备了肉桂醛/β环糊精包合物,将其添加到聚乳酸（PLA）溶液中,利用静电纺丝技术制备PLA/肉桂醛复合纳米纤维膜。利用扫描电子显微镜(SEM)探讨了静电纺丝条件对PLA纳米纤维膜纤维直径及表面形貌的影响,通过傅里叶变换红外光谱(FTIR)对PLA/肉桂醛复合纳米纤维膜做了特征官能团分析,并对其热力学性能、力学性能及抗菌性能进行了表征。结果表明,制备的PLA/肉桂醛复合纳米纤维膜纤维形态良好,平均直径为175 nm,FT IR研究显示肉桂醛与PLA之间属于物理混合。该复合纳米纤维膜热分解温度265.52 ℃,拉伸强度为2.45 MPa,对大肠杆菌、金黄色葡萄球菌和枯草芽孢杆菌都具有抑菌性,其中对金黄色葡萄球菌的抑菌性最强。     

静电纺聚偏氟乙烯及其复合纳米纤维膜在过滤领域的研究进展

静电纺丝作为一种可以制备纤维直径几纳米至几微米之间超细纤维技术,是目前获得纳米尺寸纤维最有效的方法之一,聚偏氟乙烯(PVDF)也因其优异的物理和化学性能在众多领域备受青睐。近年来,利用静电纺丝技术制备直径分布、孔径大小以及所需性能等各方面达到指定要求的PVDF及其复合纳米纤维膜成为了国内外学者的研究热点。目前,已成功制备出了多种高性能化和多功能化的PVDF纳米纤维膜,并在医学、电工电气以及过滤等诸多领域有着十分广阔的应用前景。文中简述了静电纺PVDF及其复合纳米纤维膜的原理和影响因素,对电纺PVDF及其复合纳米纤维膜在空气过滤、油水分离以及重金属吸附等过滤领域的应用进行了介绍,指出电纺PVDF及其复合纳米纤维膜可能存在的问题及发展前景。     

静电纺纳米纤维复合梯度型空气过滤材料的研究进展

概述了静电纺纳米纤维及其复合梯度过滤材料的特性,详述了国内静电纺纳米纤维复合梯度型空气过滤材料的制备、过滤模型理论及数值模拟等研究进展。基于不同纤维层过滤不同粗细颗粒物,每一层纤维网发挥各自独特作用,可采用多种结构和折叠结构复合,增大过滤面积,制备多层梯度的静电纺纳米纤维复合滤材,使滤材具有高效低阻、容尘量大、使用寿命长等特点,是未来空气滤材的重点研发方向;同时应加强过滤模型设计与数值模拟研究,通过滤材的应用数据不断修正模型,促进滤材性能的改进。     

复合中空纤维超滤膜的研制

本文就复合中空纤维超滤膜的制备工艺和成膜条件对膜性能影响进行了系统的研究，实验表明，对外压式中空纤维膜，内凝固液条件的改变，主要影响复合膜的内致密层，进而影响膜的透过通量，但对膜的截留孔径无影响，随空中行走距离增大，膜的透过通量减小，截留孔径增大。另外，通过基膜的选定与内凝固液的调节，复合中空纤维膜的分离孔径主要取决于复合层膜，即在适宜的条件下，基膜不影响复合膜的分离孔径，同时也不决定复合中空纤维     

新型高精度过滤材料的设计与开发

高温烟气过滤材料通过纺织材料的微孔结构对烟气中的粉尘进行拦截,从而达到过滤清洁的目的。传统针刺过滤材料受工艺设备的影响,滤料结构中孔径较大,对直径极其微小的粉尘颗粒过滤性差,从而影响滤料的过滤精度。采用全水刺加工工艺,结合超细纤维层结构,制备了全水刺超细纤维复合滤料。与传统针刺滤料、覆膜滤料以及超细纤维针刺滤料相比,全水刺超细纤维复合滤料具有更微小的孔径,且滤料结构中没有较大的穿透性针孔结构,产品可以有效拦截更微小的粉尘颗粒,过滤性能更好,同时测试压差与针刺滤料水平相当,性能更优良,适用于多种高精度过滤工况环境。     

Preparation and Properties of PVDF/Fe3O4 Nanofibers with Magnetic and Electret Effects and their Application in Air Filtration

Electrospun electret filter material is widely studied because of its excellent removal effect on particulate matter from air streams. Here, a kind of high efficiency and low pressure drop nanofiber (NF) membrane with both electret effect and magnetic effect is developed, and compounded it with glass fiber mesh and polyester (polyethylene terephthalate) mesh to prepare a sandwich structure of NF anti‐haze window screen. Under the synergistic effect of magnetic particles, when the density is 2.06 g m^?2, the filtration efficiency of NF anti‐haze window screen can reach 99.95% for the fine particles below 0.3 µm, while the filtration pressure drop is only 58.5 Pa, with good light transmittance and excellent breaking strength (6.32 MPa). Therefore, polyvinylidene fluoride/Fe₃O₄ composite NF membrane has a potential application prospect in the field of air filtration.     

多级结构静电纺纳米纤维膜在空气过滤领域研究进展

静电纺纳米纤维膜具有纤维直径小、比表面积大、孔隙率高等优势,使其在空气过滤领域具有广阔的应用前景。相比特殊结构的纳米纤维膜,常规的静电纺纤维膜堆积密度大、过滤阻力高,增加了在实际使用中的能源消耗。从静电纺纤维膜结构和过滤性能的角度探讨了高效低阻空气过滤纳米纤维膜的构筑,介绍了珠粒、突起和多孔结构纤维膜在空气过滤领域的研究进展,指出了多级结构静电纺纳米纤维膜是高效低阻空气过滤膜的重点研究方向。     

Study on the properties of the electrospun silk fibroin/gelatin blend nanofibers for scaffolds

Silk fibroin (SF)/gelatin blend nanofibers membranes as scaffolds were fabricated successfully via electrospinning with different composition ratios in formic acid. The formation of intermolecular hydrogen bonds and the conformational transition of SF provided scaffolds with excellent mechanical properties. FTIR and DTA analysis showed the SF/gelatin nanofibers had more β‐sheet structures than the pure SF nanofibers. The former's breaking tenacity increased from 0.95 up to 1.60 MPa, strain at break was 7.6%, average fiber diameter was 89.2 nm, porosity was 87%, and pore diameter was 142 nm. MTT, H&E stain, and SEM results showed that the adhesion, spreading, and proliferation of human umbilic vein endothelium cells (HUVECs) and mouse fibroblasts on the SF/gelatin nanofibers scaffolds were definitely better than that on the SF nanofibers scaffolds. The scaffolds could replace the natural ECM proteins, support long‐term cell growth, form three‐dimensional networks of the nanofibrous structure, and grow in the direction of fiber orientation. Our results prove that the addition of gelatin improved the mechanical and biological properties of the pure SF nanofibers, these SF/gelatin blend nanofiber membranes are desirable for the scaffolds and may be a good candidate for blood vessel engineering scaffolds. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

纳米纤维膜在空气净化中的应用研究进展

面向空气净化的应用需要,开发高效净化材料已成为研究热点之一,其中具有相互连贯孔结构的纳米纤维膜在高效空气净化领域展示出巨大的应用前景。对于纳米纤维膜对空气净化效果的评估指标通常包括过滤效率和过滤阻力。本文介绍了串珠、蛛网和复合等结构纳米纤维膜的研究进展,分析了驻极式纳米纤维膜在高效除尘方面的应用现状,探讨了银纳米颗粒和半导体金属氧化物改性纳米纤维膜在抗菌和除有机易挥发性气体等多功能性空气净化中的应用可行性,指出了高效低阻、功能化是纳米纤维膜用于空气净化领域的研究重点。并提出今后应高度关注多污染物对纳米纤维空气净化膜性能的影响,深入研究具有多功能协同作用的纳米纤维空气净化膜,以期获得更广泛的应用。     

Characterization of filter media prepared from aligned nanofibers for fine dust screen

Nanofibers for fine dust filters of four structures (random, aligned, orthogonal, and nanofiber net) were prepared by electrospinning method using polymers such as PAN and PA6. While conventional electret filters experienced deterioration problems in fine dust(PM_1.0) capture as its surface charge decayed, the electrospun nanofibers prepared contributed to the removal capacity. The filters from aligned fibers showed high quality factors ( q _F : filter performance indicator) and filtration efficiency from 22 to 50% depending on particle size than simple electret media at a face velocity of 15.92 cm/s. The fiber structure of nanofiber net (NFN) presented almost absolute collection efficiency, particularly on dust particles smaller than 300 nm. Furthermore, the composite filters which are composed both of a commercial electret mask filters and nanofiber nets effectively enhanced the overall filtration efficiency by 59.46%, resulting in more than 99% for PM_1.0. Consequently, electrospun polymer nanofibers offer a promising plausible mask filter material with air permeability. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48166.     

Characterization and cell response of electrospun Rana chensinensis skin collagen/poly(l‐lactide) scaffolds with different fiber orientations

Collagen was extracted from Rana chensinensis skin supplied from byproducts via an acid enzymatic extraction method. The R. chensinensis skin collagen (RCSC) and poly(l ‐lactide) (PLLA) were blended at a 3:7 ratio in 1,1,1,3,3,3‐hexafluoroisopropanol (HFIP) at a concentration of 10% (g/mL) and electrospun to produce nanofibers in an aligned and random orientation. For comparison, pure PLLA nanofibrous membranes with aligned and random nanofiber orientations were also produced. The secondary structure of the RCSC nanofibers was investigated by circular dichroism to confirm that the extracted substance was collagen. The presence of collagen in the blend nanofiber was verified by LSCM. The blended nanofibers showed uniform, smooth, and bead‐free morphologies and presented a smaller fiber diameter (278 and and 259 nm) than the pure the ones of PLLA (559 and and 439 nm) nanofibers. It was found that the addition of RCSC and the modification of the nanofiber's orientation affected the fiber's diameter and the crystallization of PLLA. The cell viability studies with human fibroblast cells demonstrated that the RCSC/PLLA nanofibrous membranes formed by electrospinning exhibited good biocompatibility and that the aligned scaffolds could regulate the cell morphology by inducing cell orientation. The empirical results in this study indicated that the aligned RCSC/PLLA nanofibrous membrane is a potential wound dressing candidate for skin regeneration. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45109.     

Fabrication and Characterization of Highly Oriented Composite Nanofibers with Excellent Mechanical Strength and Thermal Stability

Here, highly‐oriented poly(m‐phenylene isophthalamide)/polyacrylonitrile multi‐walled carbon nanotube (PMIA/PAN‐MWCNT) composite nanofiber membranes with excellent mechanical strength and thermal stability are successfully produced using electrospinning. It is demonstrated that the cooperation of multi‐walled carbon nanotubes (MWCNT) and high‐speed rotating collection is beneficial to the acquisition of highly oriented fibers and effectively improves the mechanical strength of the membrane along the orientation direction. Specifically, the tensile stress of poly(m‐phenylene isophthalamide)/polyacrylonitrile (PMIA/PAN) membrane is enhanced significantly from 10.6 to 20.7 MPa, benefiting from the highly oriented alignment of the fibers as well as the reinforcing effect of MWCNTs on the fibers. Furthermore, the stressing process of single fiber and fiber aggregates is carefully simulated, and the influence of MWCNTs on the mechanical properties of PMIA/PAN‐MWCNT membranes is analyzed comprehensively, providing a meaningful auxiliary means for the study of mechanical properties. In addition, the composite nanofiber membrane has the advantages of both PMIA and PAN, possessing high temperature resistance, flame‐retardancy, and chemical stability, for an ideal high‐temperature material. In short, the as‐prepared PMIA/PAN‐MWCNT composite membrane with excellent comprehensive property emerges a promising application in many fields, especially in high‐tech.