PVP/FF复合纳米纤维的制备与表征

采用静电纺丝技术制备了聚乙烯吡咯烷酮/二苯基丙氨酸(PVP/FF)复合纳米纤维;考察了FF含量、纺丝液流速对电纺纤维形貌及其平均直径的影响;利用扫描电镜对纤维表面形态进行了观察,通过X射线衍射和热重分析考察了纳米纤维中FF的存在状态及纳米纤维的热稳定性;通过全反射红外光谱分析了FF与PVP之间的相互作用。结果表明:当复合纤维中FF质量分数小于2%时,共混溶液的可纺性较好;复合纳米纤维直径随着FF含量的增大而先减小后增加,当FF的质量分数增加到5%时,复合纳米纤维的直径也相应增大;随着纺丝液流速的增大,复合纳米纤维的直径有逐渐增大的趋势,当纺丝液流速在0.2～0.6mL/h时,复合纳米纤维形貌较佳,纤维直径分布均匀,表面光滑无颗粒;PVP/FF复合纳米纤维中FF与PVP发生复合作用处于分散的无定形状态,分解温度范围变宽;FF与PVP之间具有良好的相容性。     

静电纺丝制备PANi/PEO微/纳米纤维的研究

采用静电纺丝制备了PANi/PEO微/纳米纤维,研究了纺丝液中PANi/PEO的质量比、纺丝电压、注射流速和喷丝针头孔径对纤维形貌的影响.研究结果表明,PEO含量的增加不仅会增强纺丝液的成纤能力,也会增大纤维的平均直径;纺丝电压的提高有利于纤维的细化,但断丝现象也增强;纤维的平均直径随注射流速和喷丝头孔径的增大而增大.所制备出的PANi/PEO纤维直径分布为258～843 nm.     

芳基乙炔树脂复合电纺纳米纤维的制备及其形貌研究

由二乙烯基苯经过溴化加成-脱溴化氢制备芳基乙炔,将芳基乙炔进行预聚得到一定粘度的芳基乙炔预聚物。采用静电纺丝制备了芳基乙炔预聚物/PAN复合电纺纤维。将复合纤维在250℃下进行热处理,然后在氮气氛中煅烧。用FESEM、FTIR分析了复合纤维的形态和化学结构的变化。结果表明,当芳基乙炔预聚物与PAN质量比为1时,复合纤维经过热处理后能保持纤维形状,预聚时引发剂AIBN的引入更有利于复合纤维碳化后保持纤维形状,经900℃煅烧后复合纤维为PAA/碳纳米纤维。     

TiO2纳米纤维的电纺制备与表征

以PVP作为络合剂与Ti（C4H9O）4反应制得前驱体,采用静电纺丝法制得PVP／TiO2纳米复合纤维后在马弗炉中煅烧,并采用SEM、TG—DTA、XRD等对纳米纤维进行了表征。结果表明：适当增加Ti（C4H9O）4浓度、增加静电电压、减小喷射速度和升高煅烧温度,电纺丝纤维直径变细;PVP／TiO2复合纤维煅烧至550℃时得到的为纯TiO2;经400℃、600℃、700％、900％煅烧后分别得到开始出现锐钛矿型的TiO2、以锐钛矿型的TiO2为主、以金红石型的TiO2为主和完全金红石晶型的TiO2纳米纤维。     

预氧化温度对静电纺Co/C复合纳米纤维形貌与结构的影响

通过调节静电纺丝过程环境因素制备了CoAc_2/PAN前驱体纤维,再经过热处理得到Co/C复合纳米纤维,分析了预氧化温度对纤维形貌与结构的影响。研究结果表明:当预氧化温度为160℃时,纤维中的PAN未形成稳定的耐热梯形结构,在碳化时纤维扭曲,生成枝节状物质;当预氧化温度为230℃时,碳化后可得到表面光滑、均匀,结构完好的Co/C复合纳米纤维;当预氧化温度为300℃时,纤维中的聚合物大分子遭到破坏,导致后续的碳化结晶过程无法正常进行,纤维形成颗粒聚集态。     

PLA/SPI复合纤维的电纺制备与表征

以聚乳酸（PLA）和大豆分离蛋白（SPI）为原料,采用静电纺丝技术,制备了PLA/SPI复合纤维。采用FT-IR、SEM、XRD等分析手段对复合纤维进行表征。结果表明：PLA/SPI复合纤维中PLA和SPI通过氢键缔合,纤维直径分布在100~300nm之间。     

静电纺丝制备复合纳米纤维方法的研究进展

近年来,复合纳米纤维因其具有优异的特性而引起国内外广泛关注.简要阐述了静电纺丝制备纯纳米纤维的方法,重点综述了静电纺丝构建复合纳米纤维方法的研究进展。     

静电纺无机纳米纤维的研究进展

综述了静电纺丝制备无机纳米纤维的最新研究进展,主要介绍了电纺氧化物纳米纤维和多组分纳米纤维的研究进展,说明了各种无机纳米纤维的特性、应用前景,并且指出其不足以及今后研究的主要方向.     

碳纳米管/聚合物纳米复合纤维静电纺丝研究进展

简述了静电纺丝装置的发展及其基本原理;介绍了静电纺丝制备碳纳米管/聚合物纳米复合纤维的技术进展,主要技术是碳纳米管在聚合基体中的分散性以及二者之间的界面结合力;详述了碳纳米管/聚丙烯腈纳米复合纤维和碳纳米管/聚氧乙烯(PEO)纳米复合纤维的制备及技术进展。指出今后应进一步发挥碳纳米管的性能,改进静电纺丝装置。     

静电纺纳米纤维的制造

静电纺丝概念出现在1934年，目前在实验室利用静电纺丝法加工纳米纤维有大量研究，但实际应用和产业化研究的较少。静电纺丝法工业化生产纳米纤维目前最可能的材料是聚乙烯醇（PVA）、聚氧化乙烯（PEO）、聚丙烯腈（PAN）、尼龙、聚乳酸（PLA）和聚氨酯（PU）。但上述原料采用的纺丝工艺主要是溶液纺丝，每个喷嘴生产的纤维量只是0．01g/min以下，与熔喷法取得的0.15-0．5g／min相比低很多，因此需要采取多喷嘴系统来提高生产率。本文介绍了静电纺装置的应用发展和一些聚合物在实验室到生产范围内生产纳米纤维的技术。     

Zirconium nitride (ZrN) fibers prepared by carbothermal reduction and nitridation of electrospun PVP/zirconium oxychloride composite fibers

Zirconium nitride (ZrN) fibers were synthesized by carbothermal reduction and nitridation of composite fibers obtained by electrospinning. The structure and morphology of ZrN fibers were characterized by the scanning electron microscopy (SEM) and transmission electron microscopy (TEM). After calcinations at 1600 °C, the surface of ZrN fibers with average diameter about 500 nm is rough but the continuous microstructure was still maintained by the connection of irregular fine particles. The diameter of ZrN crystalline was in the range of 100–500 nm. Both X-ray diffraction (XRD) and Raman spectroscopy analysis indicated that the zirconium nitride fibers have a NaCl-structure cubic cell and the better crystallinity of grains.     

预处理棉短纤维/EPDM复合材料的性能研究

采用一种含醚键和羟基等多官能团氟硅化合物(加工助荆M)和一种脂肪酸酯磺酸盐化合物(分散剂FJ)分别预处理废旧棉短纤维(SCF),并研究预处理SCF对SCF/EPDM复合材料的硫化特性和物理性能的影响.结果表明,适量的加工助剂M或分散剂FJ均可改善SCF在EPDM中的分散性,而对胶料的硫化特性影响不大;加工助剂M能增强SCF与EPDM的界面粘合,从而提高复合材料的撕裂强度和拉断伸长率.     

UHMWPE／UHMWPP冻胶体系的流变行为研究

研究了超高相对分子质量聚丙烯（UHMWPP）的加入对超高相对分子质量聚乙烯（umfwPE）冻胶体系粘性行为、非牛顿指数、结构粘度指数的影响。结果表明：UHMWPP在UHMWPE／UHMWPP共混体系中起到了润滑剂的作用,使体系的表观粘度降低,非牛顿指数升高,结构粘度指数下降。其中,UHMWPP添加量为5％时,冻胶体系的可纺性最佳。     

The effect of solution properties on the morphology of ultrafine electrospun egg albumen–PEO composite fibers

Biocompatible composite fibers suitable for food and medical applications were electrospun from egg albumen (EA) and poly(ethylene oxide) (PEO) at a flow rate of 1.8 mL/min, at an applied voltage of 22 kV and a capillary to target distance of 15 cm. The ratio of EA to PEO dispersed in formic acid was varied from 1:0 to 1:0.1, 1:0.3, 1:0.6 and 0:1. The influence of dispersion properties such as viscosity, surface tension and electrical conductivity on the morphology of electrospun fibers was investigated. As the ratio of PEO increased, viscosity, surface tension, and conductivity decreased. Electrospun fibers had diameters of 188 ± 21, 289 ± 33, 470 ± 32 and 202 ± 20 nm for EA–PEO composite ratios of 1:0.1, 1:0.3, 1:0.6, and 0:1, respectively. Pure EA did not form fibers, but was deposited as beads instead. Results were attributed to increasing entanglement of the two polymers as the concentration of PEO in the solution increased leading to larger diameters of electrospun fibers. Compositional analysis of fibers spun from mixed dispersions using FTIR and TGA indicated that fibers were composed of both EA and PEO, but that fibers contained larger concentrations of PEO than the original dispersions. Investigation of thermal properties by DSC showed the absence of a melting point in 1:0.1 and 1:0.3 EA–PEO fibers. At an EA–PEO ratio of 1:0.6, a melting point characteristic of PEO was identified but enthalpy was significantly smaller than that of pure PEO which could possibly be attributed to molecular interactions between the two polymers.     

PP／PET合金纤维的形态和热性能研究

用聚丙烯接枝丙烯酸(PP-g-AA)作增容剂,制备了PP／PET共混合金纤维。对合金纤维碱处理后的表面以及拉伸断裂后的断面形态进行SEM观察,结果表明分散相PET原位形成微纤。DSC研究结果显示,PET在复合体系中起到了异相成核的作用,使PP的结晶速率加快,同时发现加有增容剂PP-g-AA的结晶性能稍有下降,说明增容剂起到了良好的增容效果。     

Preparation of core/shell PVP/PLA ultrafine fibers by coaxial electrospinning

This study investigated the process feasibility and stability of core/shell structured bicomponent ultrafine fibers of poly(vinyl pyrrolidone) (PVP) and poly(D ,L ‐lactide) (PLA) by coaxial electrospinning. The morphological structure of the core/shell ultrafine fibers was studied by means of scanning electron microscopy, transmission electron microscopy, and X‐ray photoelectron spectroscopy. Results suggested that PVP/PLA core/shell ultrafine fibers with drawbacks could be produced from 6 or 8% PVP solutions (inner) in the mixture of N,N‐dimethlformamide (DMF) and ethanol and a 22% PLA solution (outer) in DMF and acetone when the flow rates of inner and outer fluids were 0.05 and 0.1 mL/h, respectively. The tensile modulus and tensile strength of the core/shell PVP/PLA membrane were dramatically lower than those of the electrospun PLA membrane, and its water uptake was twice more than that of the PLA membrane. Membranes made from the biodegradable core/shell ultrafine fibers could be potentially used in loading bioactive molecules for tissue regeneration. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 39–45, 2006     

静电纺丝制备MWNTs/PVA/PEO复合超细纤维

采用硝酸对多壁碳纳米管(MWNTs)进行纯化处理,利用表面活性剂十二烷基磺酸钠(SDS)或聚乙烯醇(PVA)对纯化后的MWNTs进行了表面修饰,将修饰后的MWNTs添加到PVA和聚氧化乙烯(PEO)共混水溶液中,通过静电纺丝制备了MWNTs/PVA/PEO复合超细纤维。结果表明:PVA修饰的MWNTs比SDS修饰的MWNTs在PVA/PEO纺丝液中有更好的分散稳定性。随MWNTs添加量的增加,纤维的平均直径减小;当添加PVA修饰的MWNTs质量分数为0.53%时,纤维平均直径达368 nm,且纤维表面光滑、分布均匀。     

Controlled release behavior of PCL/PEO/activated carbon composite microcapsule

Microcapsules, consisting of hydrophobic poly(ε-caprolactone), hydrophilic poly(ethylene oxide), and activated carbon, were prepared by an oil-in-water emulsion solvent evaporation method with the aim of reducing the burst effect and controlling the release behavior. Scanning electron microscopy was used to study the morphology and size of microcapsules. UV-Vis spectroscopy was used to investigate the release of model drug. Poly(ε-caprolactone)/poly(ethylene oxide) microcapsules showed the faster and higher release as the content of poly(ethylene oxide) increased due to the higher swelling and the selective dissolution. Significant reduction in the burst effect and prolonged drug release were obtained by incorporation of microporous activated carbon in the microcapsules.     

PVP/BiOCl/BiOBr的制备及其光催化降解联苯胺性能研究

通过超声分散和溶剂热法协同作用,将PVP复合到BiOCl/BiOBr材料的表面,合成PVP/BiOCl/BiOBr复合材料,通过调整NaCl及NaBr投加量,优化光催化剂中BiOBr与BiOCl的复合比。使用XRD、SEM和BET,研究复合前后光催化剂结构形态、比表面积及孔径的变化。结果表明,在PVP作用下,复合比为1∶1的BiOCl/BiOBr的光催化剂,其结构由密集型松针状结构转变为超薄多层的玫瑰花瓣片状结构,其比表面积较未改性的BiOCl/BiOBr显著提升。可见光照射下光催化降解联苯胺实验结果显示,照射180 min, PVP-BiOCl/BiOBr-1/1的联苯胺降解效果最佳,降解率为96.03%,约是原始BiOCl/BiOBr的1.57倍。结合自由基捕获实验结果,分析了PVP-BiOCl/BiOBr光催化降解联苯胺的可能机理。