海藻酸钠/PVA水溶液体系的无针静电纺丝

以去离子水为溶剂,分别配制质量分数为2%的海藻酸钠溶液和8%的聚乙烯醇(PVA)溶液,将两种溶液分别以体积比5∶5、4∶6、3∶7、2∶8、1∶9均匀混合,并测试混合溶液的粘度、电导率、表面张力等参数。通过无针静电纺丝法制得纳米纤维,采用扫描电子显微镜观察纳米纤维表面形貌。结果表明:共混液电导率、粘度都随海藻酸钠的增加而增加。海藻酸钠和PVA溶液体积比为5∶5时,纺丝效果较好,纤维膜成形良好,纤维直径分布均匀,为100~210 nm。     

静电纺聚氨酯纳米纤维非织造布的制备

研究了聚氨酯在几种常见有机溶剂中的溶解性能,寻求静电纺丝最佳溶剂及配比,并采用静电纺丝法制备纳米级聚氨酯纤维膜。通过改变共混溶剂的质量比、纺丝液的浓度、纺丝电压、挤出速度和接收距离,借助扫描电子显微镜测量纤维的直径,分析了各因素对纤维形貌结构的影响。结果表明:DMF/THF共混溶剂配比为1:3时,聚氨酯纺丝液静电纺丝效果佳;在纺丝液浓度8%～12%、纺丝电压12～30kV、接收距离10～30cm范围内,能纺制出纤维直径分布在800～1500nm之间的聚氨酯纳米纤维非织造布。     

壳聚糖纺丝液性能对静电纺纤维形态的影响

配置壳聚糖(CS)与聚乙烯醇(PVA)质量比为0 ∶ 100、10 ∶ 90、20 ∶ 80、30 ∶ 70的纺丝液,并通过静电纺丝工艺制得CS/PVA纳米纤维膜.探讨纺丝液的黏度、电导率、表面张力对CS/PVA纳米纤维膜表观形貌的影响.结果表明:随着CS含量的增大,CS/PVA纺丝液黏度提高、电导率上升、表面张力下降...     

聚丙烯腈复合纳米纤维膜的制备及性能表征

采用静电纺丝技术制备口罩芯材,以获得具有纳米蛛网结构的纤维膜材料,从而赋予材料更强的空气滑移效应。采用聚丙烯腈(PAN)和不同质量分数的氯化钡(BaCl₂)制备复合纤维膜。通过电导率和黏度评价纺丝液的性能;通过扫描电镜观察纤维膜的表面形貌,以纤维膜的形貌评价材料的空气过滤效果。结果表明：加入低质量分数BaCl₂对纺丝液的黏度和表面张力的影响较小,而使纺丝液的电导率增大,有利于获得直径分布均匀的纳米纤维膜。采用PAN质量分数为15%的纺丝液,加入质量分数为0.4%的BaCl₂,制得形貌良好的PAN纳米纤维膜。采用直径300～500 nm的电中性NaCl气溶胶颗粒对纤维膜的过滤性能进行测试,结果显示纤维膜的空气过滤效率为87.27%,具有较好的过滤效果。     

静电纺TiO2/丝素纳米纤维研究

将纳米TiO2与丝素溶液用机械搅拌和超声波充分混合后进行静电纺丝,并对所得丝素甲酸纺丝液表面张力、电导率和纳米纤维进行测试.结果表明,加入纳米TiO2的丝素甲酸纺丝液表面张力和电导率均无明显变化,不同实验条件下的纤维样品直径为76～143 nm; 但纳米TiO2在丝素溶液中的分散性较差,使得所获纤维样品的均匀度下降,断头率增加.因此,静电纺TiO2/丝素纳米纤维的关键技术在于体系中纳米TiO2颗粒的分散.     

PANI-DBSA对静电纺PAN纳米纤维直径的影响

在聚丙烯腈（PAN）溶液中加入不同十二烷基苯磺酸（DBSA）掺杂浓度的PANI-DBSA,将此共混体系进行静电纺丝制备纳米纤维。表征两聚合物的相容性,测试了DBSA浓度对对纺丝液导电率的影响,分析DBSA浓度对纳米纤维直径及直径分布的影响。结果表明,PANI-DBSA的氨基与PAN共聚物中的羰基之间存在氢键相互作用,使得聚合物具有良好的相容性,随着DBSA浓度的增加,共混纺丝液的电导率增大,同时纳米纤维的直径逐渐减小,纤维直径的离散度也逐渐减小,在DBSA浓度为1.1mol/L时,纤维的平均直径最小,为116nm。     

PU/PVDF防水透气共混膜的制备及性能研究

采用静电纺丝法制备聚氨酯/聚偏氟乙烯(PU/PVDF)共混纳米纤维膜,研究PU、PVDF质量分数、溶剂体积配比、溶质质量比对纳米纤维形貌、直径及膜性能的影响,探索共混纤维膜较优制备工艺。结果表明:共混纳米纤维膜较优制备工艺为静电纺丝电压14 kV、接收距离10 cm、纺丝液质量分数12%、溶剂体积配比N,N-二甲基甲酰胺/丙酮为4/6、溶质质量比PU/PVDF为7/3,此条件下可获得具有较优防水透气性能和力学性能的共混膜。     

壳聚糖/PVA乙酸体系的静电纺丝实践

以乙酸为溶剂溶解壳聚糖,与适量PVA(聚乙烯醇)混合制得复合纺丝液,测量复合溶液的表面张力、电导率、黏度等参数,用来表征溶液性能。通过静电纺丝法得到纳米纤维,采用扫描电子显微镜观察纤维的表面形貌。结果表明:未添加PVA的壳聚糖乙酸体系静电纺丝困难,纺丝过程中串珠较多。将配制的壳聚糖质量分数为1%的壳聚糖/乙酸溶液与10%PVA水溶液分别以5∶5、3∶7的比例混合,在纺丝电压20 kV,溶液流速0.5 mL/h,接收距离20 cm的处理条件下,可获得直径分别为61、118 nm的纳米纤维网。     

水溶性聚乙烯醇纳米纤维毡的制备与表征

采用静电纺丝技术制备了聚乙烯醇(PVA)纳米纤维毡,主要考察了纺丝液浓度和纺丝电压对静电纺纤维形成及其微观形貌的影响。实验结果表明:纺丝液的浓度对纤维的形成和形貌起着决定性作用,随着PVA质量分数的增加,在纺丝过程中纺丝液逐渐从液滴转变为均匀的纤维,纤维直径逐渐增加,当纺丝液的PVA质量分数为6%时,纤维形貌最佳;随着纺丝电压的提高,纤维平均直径先是有一定程度的降低,但随后降低幅度变得很小。通过实验确定了制备PVA纳米纤维毡的最佳工艺为:纺丝液的PVA质量分数6%,纺丝电压18kV,接收距离11cm,挤出速度0.5ml/h。     

静电纺丝制备胶原蛋白肽/普鲁兰共混纳米纤维膜

利用静电纺丝法将胶原蛋白肽与普鲁兰共混,以水为唯一溶剂,制备纳米纤维膜,研究不同胶原蛋白肽添加量对纺丝效果的影响。分析不同胶原蛋白肽/普鲁兰配比对纺丝液溶液性质的影响,使用扫描电镜(SEM)和傅里叶变换红外光谱(FTIR)测试,分析纤维膜的微观形貌及分子间相互作用。利用高级综合热分析系统和单纤维强力仪研究纤维膜的热学及力学性能。结果表明,胶原蛋白肽含量对溶液电导率影响显著,在胶原蛋白肽/普鲁兰配比为60/40时可以得到均匀度高的纳米纤维,平均直径为300 nm,纤维膜的应力、应变值与COP含量成反比。拟合结果显示,胶原蛋白肽与普鲁兰之间的分子间相互作用力以分子间氢键为主,纳米纤维膜DSC曲线上的热焓值较单一成分小,热稳定性得到改善。     

Electrospun nanofibers based on zein and red onion bulb extract (Allium cepa,L.): Volatile compounds,hydrophilicity, and antioxidant activity

Onion is rich in bioactive and volatile compounds with antioxidant activity. However, the pungent odor of volatile compounds (VOCs) released restricts its use. The encapsulation of red onion extract by electrospinning is an alternative to mask this odor and protect its bioactive compounds. The main objective of this study was to encapsulate red onion bulb extract (ROE) in different concentrations into zein nanofibers by electrospinning and evaluate their thermal, antioxidant, and hydrophilicity properties. The major VOC in ROE was 3(2H)-furanone, 2-hexyl-5-methyl. Incorporating ROE into the polymeric solutions increased electrical conductivity and decreased apparent viscosity, rendering nanofibers with a lower average diameter. The loading capacity of ROE on fibers was high, reaching 91.5% (10% ROE). The morphology of the nanofibers was random and continuous; however, it showed beads at the highest ROE concentration (40%). The addition of ROE to the nanofibers increased their hydrophilicity. The nanofibers’ antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl, nitric oxide, and hydroxyl radicals ranged from 32.5% to 57.3%. The electrospun nanofibers have the potential to protect and mask VOCs. In addition, they offer a sustainable alternative to the synthetic antioxidants commonly employed in the food and packaging industry due to their antioxidant activities.     

溶液性质对静电纺纤维形态的影响

以聚乙烯醇和聚丙烯腈溶液为原料进行静电纺丝,采用扫描电镜观察纳米级纤维的形态.在影响静电纺纳米级纤维的众多参数中,分析了溶液质量分数及其导电性对串珠和纤维直径的影响.研究发现随着溶液质量分数的增加,串珠明显减少,纤维直径增加,并得出溶液质量分数是影响串珠和纤维直径大小的主要因素;通过添加不同质量分数的盐,改善溶液的导电性,研究发现随着溶液导电性的增加,纤维直径离散度明显减少,从而得出溶液导电性是影响纤维直径离散度的主要因素.     

基于不同纺丝参数下取向纳米纤维的制备及取向度分析

为了探讨溶液性能及纺丝参数对静电纺取向纳米纤维形态的影响,制备不同质量分数的聚丙烯腈(PAN)溶液和加入不同质量分数LiCl的PAN溶液,对溶液黏度和电导率进行测试,并利用旋转的滚筒制备了不同的取向纳米纤维。研究表明:PAN溶液黏度和电导率都随着溶液质量分数的增加而增加,且黏度呈指数增加;而随着LiCl质量分数的增加,PAN溶液的黏度略有下降,而电导率显著增加。相同滚筒转速(2000 r/min)下,PAN纳米纤维的取向排列程度随着溶液质量分数的增加先提高后降低,12%的PAN纳米纤维的取向排列程度最好;而随着LiCl质量分数的增加,PAN纳米纤维的取向排列程度增加。当滚筒转速从1500 r/min增加到2500 r/min,纳米纤维的取向排列程度也增加了。     

Electrospinning of Sodium Alginate-Pectin Ultrafine Fibers

ABSTRACT:  In this study, we investigated the electrospinning process of sodium alginate-pectin fibers intended to be used as a carrier for stabilizing folic acid. Fiber-forming solutions containing 0.01% (w/w) folic acid were prepared by blending low- or medium-viscosity sodium alginate with pectin in a 70 : 30 ratio to form LSAP and MSAP solutions, respectively. Similar to other polysaccharide polymers reported previously, these solutions could not be electrospun. However, the incorporation of poly(ethylene oxide) (PEO) effectively enabled the electrospinning process. Electrospun fibers of different morphologies, ranging from fiber to fiber-bead, were obtained, depending on the blend ratio, concentration, and viscosity of the polymer-PEO solution used. Fibers electrospun from 3% MSAP/PEO (80%/20% w/w) had the smallest diameter (about 40 nm), whereas fibers containing higher PEO contents were larger in diameter. Bead-free fibers were formed when 4% LSAP/PEO (50/50) and 5% LSAP/PEO (80/20 to 50/50) were electrospun. The electrical conductivity and surface tension lowering effects of PEO on the polymer solution were likely the contributing factors for the observed electrospinning behaviors. By adjusting the formulation of the polymer solution, fibers of various morphologies may be obtained to suit different end-use applications. A study is currently ongoing to investigate the effectiveness of these fibers for stabilizing folic acid.     

Electrospinning of food-grade nanofibers from cellulose acetate and egg albumen blends

Edible nanofibrous thin films were fabricated for the first time from blend solutions of cellulose acetate (CA) in 85% acetic acid and egg albumen (EA) in 50% formic acid by electrospinning. The mass percentage ratios of CA–EA in the mixed solvents varied from 100:0 to 91:9, 77:23, 66:34 and 0:100. Effects of the blend ratios on the solution properties and morphology of the resulting electrospun products were studied. The results showed that EA lacked sufficient entanglement and also possessed very high surface tension, thereby being unable to form nanofibers. The addition of CA and surfactant (Tween40®) decreased both the electrical conductivity and the surface tension of the blends (p < 0.05), which facilitated the formation of CA–EA blend nanofibers. Scanning electron microscopic images showed that the continuity of the blend fibers was improved with an increase in the EA ratio. Fourier-transformed infrared spectroscopy and thermo-gravimetric analysis results indicated that the obtained fibers were composed of both CA and EA constituents. This study demonstrated a potential to fabricate edible nanofibers from natural food biopolymers using the electrospinning technique. Due to the properties of EA, these nanofibers could provide new functionalities with respect to in vivo-controlled release of nutraceuticals and drugs.     

静电纺再生丝素/明胶纳米纤维的结构与性能

 以质量分数为98%的甲酸为溶剂,将再生丝素与明胶以质量比70∶30进行共混静电纺丝。研究纺丝液质量分数及乙醇处理对纤维膜的结构及力学、溶解性能等的影响;测定不同纺丝液质量分数及不同厚度下纤维膜的孔隙率及孔径;在纤维膜上进行小鼠成纤维细胞(L929)和人脐静脉内皮细胞(HUVECs)培养实验。结果表明:随着纺丝液质量分数的提高或经乙醇处理后,丝素β化程度提高,纤维结晶度增大,溶失率减小,拉伸强度增大;随着纺丝液质量分数的提高,纤维膜的孔隙率减小,孔径增大,厚度增加时,纤维膜的孔隙率及孔径均减小;L929及HUVECs均能够在纳米纤维膜上黏附、生长和增殖。     

Development of novel pea flour‐based nanofibres by electrospinning method

The aim of this study was to produce pea flour and hydroxypropyl methylcellulose (HPMC)‐based novel nanofibres using electrospinning method. The effects of pH, pea flour and HPMC concentration on apparent viscosity, electrical conductivity of electrospinning solutions and nanofibre characteristics were studied. Solutions were prepared at different pH values (7, 10, 12), with different pea flour concentrations (1%, 2% w/v) and HPMC concentrations (0.25%, 0.5%, 1.0% w/v). For all pea flour concentrations, k values increased significantly with increase in pH and HPMC concentration. It also increased with increase in pea flour concentration for basic solutions. Pea flour concentration increased diameter and water vapour permeability (WVP) values of nanofibres. This study showed that electrospinning was a promising method for fabrication of homogenous pea flour and HPMC‐based nanofibres to be used in packaging industry.     

聚合物静电纺及在组织工程支架中的应用

1.浙江理工大学材料与纺织学院 浙江杭州310018 ;2.浙江大学高分子复合材料研究所 浙江杭州310027;3.浙江大学教育部高分子合成与功能构造重点实验室 浙江杭州310027     

丝素与明胶共混静电纺丝

 丝素和明胶以不同质量比共混于甲酸溶剂,将此纺丝液进行静电纺丝,并用扫描电镜观察其形态结构,分析探讨了工艺参数对其形貌和直径的影响,并与相同工艺条件下的纯丝素纳米纤维进行比较。结果表明:在丝素与明胶质量比为70∶30,纺丝液质量分数为11%,极距为13 cm,电压为22 kV的工艺条件下,静电纺纤维平均直径为83.9 nm,纤维直径分布均匀。用明胶共混不仅有利于克服低质量分数丝素纺丝液静电纺丝中出现的珠状物和断头多等问题,而且有望应用于生物组织工程中。     

部分环化聚酰胺酸的流变性及其静电纺丝

以部分环化聚酰胺酸为纺丝原液,采用高压静电纺丝法制备部分环化聚酰胺酸纳米纤维。测试了纺丝原液的流变特性和纳米纤维毡的力学性能,用红外光谱和扫描电子显微镜表征了纤维的酰亚胺化程度及其表面特征。结果表明：随着环化剂量的增加,聚酰胺酸的酰亚胺化程度增加;剪切速率提高,溶液剪切黏度减小;分子链刚性越强,黏度的降低越明显;纺丝溶液黏度提高,纤维连续而伸直、直径变大;部分环化PAA纳米纤维毡的最大拉伸强度和弹性模量分别为16.87MPa、254.77MPa。