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1.
明胶与聚乙烯醇(PVA)溶液共混得到不同配比的纺丝原液,通过测定其流变性与共混膜的力学性能,得到优化明胶-PVA共混纺丝原液固含量比为1.5∶8.5.以饱和硫酸钠溶液为凝固浴,采用湿法纺丝制得复合纤维.采用正交设计法优化复合纤维热拉伸条件为,温度200 ℃、拉伸率60%、处理时间4 min;最后对纤维进行了扫描电镜(SEM)分析及吸湿性与蛋白质含量的表征. 相似文献
2.
《化工新型材料》2016,(7)
以水为溶剂通过静电纺丝手段制备了海藻酸钠/聚乙烯醇(SA/PVA)纳米纤维膜,研究了溶液混合比例、纺丝参数、氯化钠(NaCl)和曲拉通X-100对其静电纺丝的影响,并对SA/PVA纳米纤维膜进行了XRD、FT-IR表征和力学性能测试。结果表明,溶液混配合比和纺丝参数对静电纺丝性能有着重要影响;添加0.5%(wt,质量分数,下同)的NaCl和1.5%的曲拉通X-100后能显著改善SA/PVA的静电纺丝性能。XRD和FT-IR分析表明,PVA能够破坏SA分子间作用力并形成了新的氢键。SA溶液∶PVA溶液的配合比为3∶7时,SA/PVA纳米纤维膜拉伸强度最优,达11.36MPa。 相似文献
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以羽毛角蛋白(FK)和聚乙烯醇(PVA)为原料,水为溶剂,通过静电纺丝技术制备了FK/PVA复合纳米纤维膜.探讨了复合纳米纤维中FK与PVA的相容性,研究了FK的添加对纤维膜微观形貌、结晶度、热稳定性、亲水性等性能的影响.SEM结果表明,在聚合物总质量分数为14%的条件下制备的FK/PVA复合纳米纤维,表面平整光滑,平均直径为250~320 nm,FK含量越大,直径越小.FTIR结果表明,FK与PVA具有良好的相容性,分子间存在氢键作用力.XRD结果表明,FK的加入破坏了PVA分子的规整排列,复合纳米纤维膜的结晶度下降.TG分析与接触角测试结果表明,随着体系中FK配比的增大,复合纳米纤维膜的热稳定性和亲水性均得到提高. 相似文献
5.
采用静电纺丝技术成功制备出沸石咪唑骨架材料(ZIF-8)/聚乙烯醇(PVA)静电纺丝膜。分别探究和优化了PVA浓度、纺丝电压、接收距离等参数对纤维膜形态结构的影响。对复合纳米纤维膜进行了形貌表征和成分分析。实验发现在ZIF-8的浓度为10wt%条件下,当PVA的浓度为7wt%、电压为40kV、接收距离为16cm时,可得到可纺性最好、形态均匀的纳米纤维膜,膜纤维的平均直径在240nm左右。将已经制备成功的ZIF-8/PVA复合纳米纤维用于吸附刚果红,在12h内吸附容量可达86mg/g,显示出良好的吸附能力。 相似文献
6.
将聚乙烯醇(PVA)与再生柞蚕丝素蛋白(RWSF)共混,通过静电纺丝技术制备了PVA/RWSF复合纳米纤维,在保持材料降解性能和力学强度不变的前提下,获得了具有生物活性的表面。应用正交法优选出PVA/RWSF复合纳米纤维的最佳制备工艺参数。扫描电镜观察到,各组电纺膜中纤维的形貌较好,不同参数条件下纤维的直径和均匀程度有较大差别;方差分析表明,静电纺丝过程中纺丝液浓度、PVA/RWSF质量比和纺丝电压对纤维均匀性的影响显著;结合后期验证性实验确定PVA/RWSF复合纳米纤维最佳电纺参数为电纺液浓度0.09 g/mL、PVA/RWSF质量比90/10、纺丝电压18kV、推进速度1.5mL/h、接收距离14cm,此时制备的纤维均一、纤细,重复性好。 相似文献
7.
以羽毛角蛋白(FK)和聚乙烯醇(PVA)为原料,水为溶剂,通过静电纺丝技术制备了FK/PVA复合纳米纤维膜。探讨了复合纳米纤维中FK与PVA的相容性,研究了FK的添加对纤维膜微观形貌、结晶度、热稳定性、亲水性等性能的影响。SEM结果表明,在聚合物总质量分数为14%的条件下制备的FK/PVA复合纳米纤维,表面平整光滑,平均直径为250~320nm,FK含量越大,直径越小。FTIR结果表明,FK与PVA具有良好的相容性,分子间存在氢键作用力。XRD结果表明,FK的加入破坏了PVA分子的规整排列,复合纳米纤维膜的结晶度下降。TG分析与接触角测试结果表明,随着体系中FK配比的增大,复合纳米纤维膜的热稳定性和亲水性均得到提高。 相似文献
8.
改性魔芋葡甘聚糖/生物可降解聚酯静电纺丝 总被引:1,自引:0,他引:1
为了制备改性魔芋葡甘聚糖(TDKGM)/生物可降解聚酯纳米复合纤维,以TDKGM和生物可降解聚酯(BP)为原料,三氟乙酸为溶剂,调节TDKGM和BP共混比例,采用静电纺丝方法分别制备了TDKGM/聚乳酸(PLA)、TDKGM/聚丁二酸丁二醇酯(PBS)纳米复合纤维。探讨了TDKGM与可降解聚酯共混比例对纺丝溶液的电导率、表面张力、流变性以及复合纤维直径、形貌和力学强度的影响。随着BP的增加,TDKGM/PLA共混液的表面张力从22.2 N/m降至18.2 N/m,电导率从69.7μS/m下降至39.1μS/m;TDKGM/PBS共混液的表面张力从22.8 N/m降低到17.0 N/m;储能模量、损耗模量、剪切黏度都随之降低;而TDKGM/PBS共混液的电导率变化不成线性规律。当TDKGM/PLA比例为5∶5、TDKGM/PBS比例为6∶4时得到的纤维形貌最为理想,纳米复合纤维的直径分布在400~600 nm,100~500 nm范围,纤维膜的拉伸强度分别为3.557 MPa,4.543 MPa。TDKGM和BP共混比例将影响共混液的电导率、表面张力、流变性,从而影响静电纺丝复合纤维直径分布和形貌,通过控制TDKGM和BP共混比例可以成功地纺丝出纤维直径可控、强度高的TDKGM/BP纳米复合纤维。 相似文献
9.
为改善聚乙烯醇(PVA)对相变材料十二酸十二酯(PCM)的包封稳定性与力学性能,以经戊二醛交联改性的复合分子量共混PVA作为支撑材料、以十二酸十二酯作为相变材料,采用乳液静电纺丝技术制备了PCM/PVA蓄热调温纤维.采用旋转流变仪、扫描电镜、差示扫描量热仪、温度记录仪、热红外成像仪、多功能拉伸仪等研究了O/W型PCM/PVA纺丝液的组成及电纺纤维的表面形貌、储热性能、调温性能和力学性能等.研究结果表明,以不同相对分子质量的PVA1和PVA2共混制备复合PVA,当PVA1与PVA2质量比为3:7,PVA质量分数为14.0%,PCM与PVA质量比为50:100时,PCM/PVA纺丝液具有良好的稳定性和可纺性.电纺PCM/PVA纤维具有良好的蓄热调温性、热循环稳定性、耐水稳定性和力学性能,热处理后PCM/PVA电纺纤维中的PCM几乎无泄露. 相似文献
10.
以聚乙烯醇(PVA)纺丝原液为分散介质, 常温相变材料RT27石蜡为芯材, 正硅酸乙酯(TEOS)为聚合单体形成SiO2囊壳, 通过原位聚合直接制备含有石蜡微胶囊的PVA纺丝原液, 之后通过湿法纺丝制备石蜡/PVA储能纤维。通过正交实验优化, 结合粒径分布软件, 分析各因素对微胶囊粒径的影响, 选择适合纺丝的微胶囊合成条件。采用FTIR-ATR、SEM、EDS及TEM表征了纤维及微胶囊的化学成分及形态, 通过DSC、TGA表征了微胶囊的包覆率、纤维的储能性及热稳定性。结果表明: PVA纺丝原液中合成了SiO2凝胶包裹的相变微胶囊, 其平均粒径为1.39 μm, 大小及分布适合纺丝。纤维相变焓值为45.39 J/g, 石蜡包裹率高达94.72%, 纺出纤维具有较高的储能性和较好的热稳定性。 相似文献
11.
Mehmet Cem Ece 《Journal of Engineering Mathematics》1992,26(3):415-428
The boundary-layer flow on an impulsively started translating and spinning rotational symmetric body is considered. The stream function and the swirl component of the velocity are expanded in series in powers of time. Leading and first order solutions are obtained analytically and the second order solutions are determined numerically. The results are applied to a translating and spinning sphere and the rotation is found to reduce the friction drag and facilitate flow separation. 相似文献
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The layer-by-layer buildup of poly(styrene sulfonate), poly(diallyldimethyl ammonium) and/or TiO2-nanoparticles was carried out using an automated system which allowed spraying the polyion solutions on a spinning substrate. The different spraying and spinning arrangements were studied. The films were prepared by varying ionic strength, electrolyte species (NaBr and NaF) and spraying time. The results were compared to the films prepared by using the traditional dipping method. Depending on the electrolyte and the ionic strength the thickness of the films prepared with spraying on spinning substrate was thinner than or equal to the dipped films. It was found that addition of salt on spraying solutions is necessary in order to prepare thin films with a good quality. Spraying on spinning substrate generated evenly occupied smooth surfaces. The benefits of the automated method are attributed to the noticeably lower solution consumption and to the fact that the film deposition process could be accelerated by a factor of 100 comparing to the traditional dipping method. 相似文献
14.
V. T. Kalinnikov O. G. Gromov A. P. Kuz'min G. B. Kunshina E. P. Lokshin N. V. Sidorov 《Inorganic Materials》2004,40(3):285-291
The preparation of film-forming peroxide solutions of LiTaO3 and LiNbO3 precursors is described. The solutions are used to produce LiTaO3 films on single-crystal corundum and LiNbO3 substrates by the spinning process and dip coating, followed by heat treatment, and LiNbO3 films on single-crystal corundum substrates by the spinning process. 相似文献
15.
《Composites Part B》2004,35(3):235-243
Magnetic investigations on a nanocomposite material obtained by spinning solutions of styrene–butadiene–styrene block copolymer containing barium ferrite nanoparticles onto Si wafers are reported. The effect of the spinning frequency on the magnetic features is discussed. It is observed that the magnetization at saturation is decreased as the spinning frequency is increased as the centrifuge force removes the magnetic nanoparticles from the solution. This is supported by the derivative of the hysteresis loops, which show two components, one with a high coercive field and another with a small coercive field. Increasing the spinning frequency increases the weight of the low coercive field component. The anisotropy in the distribution of magnetic nanoparticles, triggered eventually by the self-assembly capabilities of the matrix, is revealed by the difference between the coercive field in parallel and perpendicular configuration. It is noticed that increasing the spinning frequency enhances this difference. The effect of annealing the nanocomposite films is discussed. 相似文献
16.
In this paper, N-Methylmorpholine-N-Oxide (NMMO) was used as solvent for regenerated silk fibroin (RSF). Concentrated solutions with RSF content from 10 to 25 wt%
were obtained by dissolving RSF film into NMMO monohydrate. The spinning and rheological properties of RSF/NMMO·H2O solutions were studied by a simple piston type single filament spinning apparatus and HAAKE RS150L rheometer, respectively.
The results are discussed to understand the influences of shear rate, temperature and RSF concentration on the rheological
behaviors of RSF/NMMO·H2O and to choose appropriate process condition for spinning. Spinning was performed using a dry-wet spinning process. The regenerated
silk fibre was prepared successfully and the tenacity can reach to 3.07cN/dtex. 相似文献
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Bruce King Yin Liu Suresh Baskaran Richard Laine John Halloran 《Particulate Science and Technology》1992,10(3):121-132
Yttrium aluminum garnet (YAG - Y3Al5O12) fibers have been prepared by dry spinning solutions of yttrium and aluminum carboxylate polymers (precursor route) and by dry spinning aqueous oxide sols (sol-gel route). Fibers from aqueous diphasic gels are prepared by mixing a colloidal alumina sol containing 50-nm hydrous alumina with a colloidal yttria sol containing 10-nm yttrium oxide, using polyvinylpyrrolidone as a spinning aid. Fibers by the precursor route are made from spinnable THF solutions of yttrium isobutyrate and aluminum isobutyrate or from aqueous solutions of polymeric aluminum formate and yttrium acetate.
The isobutyrate materials decompose between 200-400°C to an amorphous residue. Crystallization occurs abruptly between 875°C and 900°C, forming the YAG phase directly. The formate-acetate also decomposes to amorphous residues, which form YAG at 900°C. In the diphasic gel, YAG forms gradually between 1000 and 1200°C, with intermediate products YAP (YalO3 perovskite) and/or YAM (Y4Al2O9 monoclinic). At 1500°C, single phase YAG is obtained as pore-free fibers with 500 nm grains. 相似文献
The isobutyrate materials decompose between 200-400°C to an amorphous residue. Crystallization occurs abruptly between 875°C and 900°C, forming the YAG phase directly. The formate-acetate also decomposes to amorphous residues, which form YAG at 900°C. In the diphasic gel, YAG forms gradually between 1000 and 1200°C, with intermediate products YAP (YalO3 perovskite) and/or YAM (Y4Al2O9 monoclinic). At 1500°C, single phase YAG is obtained as pore-free fibers with 500 nm grains. 相似文献
19.
The flow behaviour during gel-spinning of semi-dilute solutions of ultra-high molecular weight polyethylene in paraffin oil
was investigated in relation to fibre strength and morphology. Shish-kebab morphologies observed in the as-spun filaments
originate from a solidification of long flow units already developed in the polymer solution during spinning. These flow units
consist of alternating bundles of elongated molecules and highly entangled clusters of unoriented molecules. Extrudate stretching
leads to a demolition of these long flow units by elastic flow instabilities. As a result, the tensile properties after hot-drawing
of the fibres are strongly reduced. The inclusion of 1 wt% aluminium stearate in the spinning solution preserves the long
bundle-like flow units even at high take-up speeds during extrusion. This additive suppresses the adsorption of the polyethylene
on the die-wall and avoids the generation of elastic turbulences. Filaments with a strength between 2.5 and 3.0 G Pa can be
obtained from these doped solutions after hot-drawing, in spite of high winding speeds up to 300 m min−1 in the spinning process. 相似文献
20.
Jiahui Guo Yunru Yu Huan Wang Han Zhang Xiaoxuan Zhang Yuanjin Zhao 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(15)
Conductive hydrogels are receiving increasing attention for their utility in electronic area applications requiring flexible conductors. Here, it is presented novel conductive hydrogel microfibers with alginate shells and poly (3, 4‐ethylenedioxythiophene): poly (4‐styrenesulfonate) (PEDOT: PSS) cores fabricated using a multiflow capillary microfluidic spinning approach. Based on multiflow microfluidics, alginate shells are formed immediately from the fast gelation reaction between sodium alginate (Na‐Alg) and sheath laminar calcium chloride flows, while PEDOT: PSS cores are solidified slowly in the hollow alginate hydrogel shell microreactors after their precursor solutions are injected in situ as the center fluids. The resultant PEDOT: PSS‐containing microfibers are with features of designed morphology and highly controllable package, because material compositions or the sizes of their shell hydrogels can be tailored by using different concentrations or flow rates of pregel solutions. Moreover, the practical values of these microfibers in stretch sensitivity and bending stability are explored based on various electrical characterizations of the compound materials. Thus, it is believed that these microfluidic spinning PEDOT: PSS conductive microfibers will find important utility in electronic applications requiring flexible electronic systems. 相似文献