大豆蛋白/聚丙烯腈共混纤维结构性能研究

研究了以二甲基亚砜为溶剂,经湿法纺丝所制备的大豆蛋白/聚丙烯腈共混纤维的结构性能。红外光谱分析表明:共混纤维主要组成为聚丙烯腈和大豆蛋白质;扫描电镜观察发现:纤维的表面有凸起颗粒及较深的沟槽;共混纤维的断裂强度略有降低,断裂伸长率基本不变;纤维的表面接触角及回潮率的测试表明:共混纤维的吸湿性得到提高。     

Modification of polyacrylonitrile (PAN) fiber by blending with N‐(2‐hydroxy)propyl‐3‐trimethyl‐ ammonium chitosan chloride

N‐(2‐Hydroxy)propyl‐3‐trimethylammonium chitosan chloride (HTCC) was synthesized by the reaction of glycidyltrimethylammonium chloride (GTMAC) and chitosan. The reaction product was a water‐soluble chitosan derivative, and showed excellent antimicrobial activity. HTCC was blended with polyacrylonitrile (PAN) using an NaSCN aqueous solution as a common solvent. The blend solution was transparent and stable up to 6 months without phase separation. The PAN/HTCC blend fibers were prepared via a wet spinning and drawing process. Thermal, electrical, and mechanical properties as well as antimicrobial activity were investigated. It was found that the antistatic property and antimicrobial activity of the blend fibers could be achieved by adding only a small amount of HTCC. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2258–2265, 1999     

PAN/AN-co-ADMH共混纤维的氯化漂洗处理

采用聚丙烯腈(PAN)与丙烯腈(AN)/3-烯丙基-5,5-二甲基乙内酰脲(ADMH)共聚物共混湿法纺丝制备了PAN/AN-co-ADMH共混纤维,用质量分数1%的次氯酸钠溶液对共混纤维进行了漂洗处理,探讨了氯漂条件对共混纤维氯含量的影响,考察了氯漂处理后的共混纤维的耐洗涤性及再生性。结果表明:随漂洗液温度升高和氯化漂洗时间增加,共混纤维中氯含量增加;漂洗时间继续增加,纤维氯含量增势变缓;纤维氯含量随洗涤次数或漂洗次数增加均减少。     

凝胶染色过程中腈纶沿纺程的结构性能变化的研究

采用湿法纺丝工艺制备腈纶(即聚丙烯腈(PAN)纤维),研究了凝胶染色过程中PAN纤维在不同工序段的结构和物理性能.结果表明:沿着纺程,PAN纤维的直径逐渐减小,纤维的玻璃化转变温度和结晶度逐渐提高;在水洗后PAN纤维表面有明显的微观结构缺陷、且无定形区占比高;经过热拉伸和干燥致密化之后,纤维致密化,结晶度大大增加,凝胶...     

PAN/PMMA共混制备纳米碳纤维的结构与性能

以N,N-二甲基甲酰胺(DMF)为溶剂,以聚丙烯腈(PAN)为碳前驱体,聚甲基丙烯酸甲酯(PMMA)为热裂解聚合物,制备PAN/PMMA溶液共混体系,经湿法纺丝及碳化工艺制备了纳米碳纤维(CNFs);讨论了影响CNFs形态、尺寸的主要因素,通过傅里叶变换红外光谱、X射线衍射、拉曼光谱和电导率测试等对CNFs进行了表征。结果表明:相对分子质量为8.0×10~4的PAN与PMMA以质量比30/70进行共混纺丝和碳化,可以得到CNFs;增加原丝的拉伸倍数有利于减小CNFs的直径,当拉伸倍数提高到6时,CNFs直径为50～150nm;碳化温度为800℃时,CNFs出现石墨相结构;提高碳化温度有利于CNFs石墨化结构的形成与电导率的提高。     

Preparation of polyacrylonitrile and cellulose acetate blend fibers through wet‐spinning

Fibers containing both polyacrylonitrile (PAN) and cellulose acetate (CA) were prepared through wet‐spinning by using N,N‐dimethylformamide (DMF) as a solvent. Compatibility of PAN and cellulose acetate blend (PCB) fibers was investigated by means of scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and infrared (IR) spectrophotometry. The absorptive capacity and mechanical properties of the fibers were measured. It was observed that the surface and the cross section of PAN fibers were quite smooth and free from voids and microcracks, whereas cracks and voids were present on the surface and cross section of blend fibers, which increased with the incorporation of CA in the blend. Moisture regains of blend fibers were quite high while their tensile properties showed a partial decrease. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2000–2005, 2007     

硫氰酸钠法高吸湿腈纶的研制

研究了丙烯酸对腈纶的吸湿改性。探讨丙烯酸共聚物的水溶性随丙烯酸-丙烯腈的共聚比而变化的规律,丙烯酸含量对改性腈纶的力学性能,回潮率和保水率的影响。结果表明,采用丙烯酸-丙烯腈投料比为1:5.7的共聚物溶液和常规腈纶纺丝原液共混纺丝,在纤维中引入质量分数2.5％的丙烯酸时,制得的高吸湿腈纶强度为1.9cN/dtex,伸长40％,回潮率和保水率分别为7.0％和20.8％。     

共混法制备酸性可染聚丙烯腈纤维

用含有碱性基团的丙烯酸氨基酯(TAM)与丙烯腈(AN)单体共聚,其共聚物与聚丙烯腈(PAN)共混,经湿法纺丝制备酸性染料可染PAN共混纤维。结果表明,AN／TAM共聚物与PAN有良好的相容性。随着TAM含量的增加,PAN共混纤维结晶度下降,力学性能下降。纤维中TAM质量分数5％较好,PAN共混纤维酸性染料上染率大于80％。     

PAN／PS共混中空纤维超滤膜研究

本文将聚丙烯腈（ＰＡＮ）和聚砜（ＰＳ）材料共混，采用二甲基甲酰胺（ＤＭＦ）作溶剂，以干－湿纺丝工艺制备中空纤维超滤膜，研究了二种膜材料和溶剂的热力学性质，确定合适的共混体系，并相同共混比下共混物浓度对中空纤维超滤膜性能影响。以磷酸三乙酯（ＴＥＰ）和冰醋酸作为添加剂，分别观测其不同含量膜性能变化规律。认为磷酸三乙酯作用添加剂有一定的优越性。提高铸膜液温度，有助于增强ＰＡＮ－ＰＳ－ＤＭＦ所组成部分互溶     

不同玻璃化转变温度聚丙烯腈共混溶液的流变行为研究

将两种不同玻璃化转变温度丙烯腈共聚物A(常规PAN)与B(改性PAN)配置成新的纺丝原液(溶剂为NaSCN溶液),利用旋转流变仪研究了这种共混溶液的流变行为,结果表明:所得共混纺丝原液属于切力变稀流体,相对于常规聚丙烯腈原液,其粘度较大,并且随着B含量的增加,其出现凝胶的概率增加,凝胶点向低频方向移动,形成网络结构,体系弹性增加;这种共混纺丝原液具有较小的粘流活化能,粘度随温度的变化小,有利于纺丝成型。     

Blend fibers of polyacrylonitrile and water‐soluble chitosan derivative prepared from sodium thiocyanate solution

A water‐soluble chitosan derivative of N‐(2‐hydroxy)propyl‐3‐trimethylammonium chitosan chloride (HTCC), synthesized by the reaction of chitosan and glycidyltrimethyl ammonium chloride, and polyacrylonitrile (PAN) were blended using 46% (w/w) NaSCN aqueous solution as a common solvent. The total polymer concentration of blend solution was fixed at 12% (w/w), and the relative composition of PAN/HTCC in the blend solution varied from 0/100 to 80/20 by weight. The PAN/HTCC blend fibers with the appropriate physical property were prepared by a wet spinning and drawing process. The effect of HTCC content on the structural change, miscibility, and ability to be dyed of the blend fibers was investigated. The optical and scanning electron microscopic observation gave no indication of phase separation up to 20% HTCC content. Differential scanning calorimetry and dynamic mechanical measurements of the blend fibers show single glass transition temperatures that increase with increasing blend ratio of HTCC. All the experimental results exhibit that the blends are miscible on the molecular scale. The blend fibers could be dyed with an acid dye. This enhanced ability of the blend fibers to be dyed with acid dyes could be useful for one‐step dyeing when mixed with other fibers, such as wool and nylon. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1620–1629, 2001     

海藻酸钙/纳米TiO_2共混纤维的制备与表征

将含固体质量分数为5%的海藻酸钠纺丝原液与纳米二氧化钛(TiO2)水分散液均匀混合,制得海藻酸钠/纳米TiO2混合纺丝原液,采用湿法纺丝,通过氯化钙凝固浴,经拉伸、水洗,制备了海藻酸钙/纳米TiO2共混纤维,研究了纳米TiO2含量对共混纤维结构及性能的影响。结果表明:纳米TiO2的加入,提高了共混纤维的力学性能;加入质量分数为0.5%的纳米TiO2,海藻酸钙大分子链上的红外特征吸收峰峰形明显变宽,共混纤维的力学性能最佳,断裂强度为2.93 cN/dtex,断裂伸长率为7.34%,优于海藻酸钙纤维;添加纳米TiO2质量分数为3%时,纳米TiO2在共混纤维中仍能较好的分散,且纤维表面光滑。加入纳米TiO2后,共混纤维的热稳定性提高。     

蓄热调温聚丙烯腈纤维的制备及性能研究

将石蜡相变微胶囊(MEPCM)添加到聚丙烯腈(PAN)的硫氰酸钠纺丝液中,通过湿法纺丝制备了蓄热调温PAN纤维,考察了MEPCM质量分数对纺丝液可纺性和纤维力学性能、热学性能及染色性能的影响。结果表明:随着MEPCM质量分数的增加,纺丝液表观黏度下降,PAN纤维的蓄热调温能力增大,纤度增大,密度减小,断裂强度和断裂伸长率下降,热分解温度略有降低;对阳离子红5GN的恒温染色速率常数增大,平衡上染量减小,半染时间缩短。     

Characteristics of polyacrylonitrile solutions and fibers varied with the dissolution process in ionic liquid

The concentrated polyacrylonitrile (PAN) solutions were prepared with 1‐butyl‐3‐methylimidazolium chloride ([BMIM]Cl) as solvent by static state, stirring, and kneading. The steady and oscillatory shear tests were carried out to investigate the viscoelastic behaviors of the PAN/[BMIM]Cl solutions by rotational rheometer. It was found that the zero shear‐rate viscosity and relaxation time of the solution prepared by kneading were lowest and the non‐Newtonian index was largest among the solution. During kneading, the gelation temperature of the viscous and homogenous solution was at the lowest temperature 22.7°C among the all three solutions. Only the solutions prepared by stirring and kneading could be spun by dry‐jet wet spinning technology. The fiber processed with the solution prepared by kneading could be drawn with a higher draw ratio, showing the larger draw ability. The supramolecular structure and properties of the fibers were studied by synchrotron wide‐angle X‐ray diffraction (WAXD) technologies, dynamic mechanical analysis (DMA), and mechanical tests. All the results showed that the kneading is an efficient method for PAN fiber spinning with [BMIM]Cl as solvent. It lead to the investigation of the methods of preparation of PAN solution in [BMIM]Cl, which affect the homogeneity of the solutions and hence the resulting characteristics of PAN fibers. POLYM. ENG. SCI., 55:558–564, 2015. © 2014 Society of Plastics Engineers     

PES/PA6的共混纺丝及其性能研究

将不同质量比的聚醚砜(PES)与聚酰胺6(PA6)共混进行熔融纺丝制得PES/PA6共混纤维;研究了共混物的流动性及其纺丝工艺,以及PES/PA6共混纤维的热稳定性和力学性能。结果表明:PA6的加入显著提高了PES的流动性,降低了纺丝温度,改善了PES的可纺性;与纯PES纤维相比,PES/PA6共混纤维的起始热分解温度有所降低,PES/PA6质量比为70/30～30/70的PES/PA6共混物的纺丝温度为320～340℃,卷绕速度为100～400 m/min,纤维的断裂强度为0.71～2.25 cN/dtex。     

成形条件对PAN原丝微孔结构及热性能的影响

将不同浓度的聚丙烯腈(PAN)原液在不同凝固浴温度下进行湿法纺丝,制得PAN原丝,再将PAN原丝在沸水浴中进行5倍拉伸。探讨了成形条件以及拉伸对PAN原丝微孔结构及热性能的影响。结果表明:当PAN纺丝原液质量分数为22%,凝固浴温度为10℃时,可以得到结构均匀致密的PAN原丝。PAN原丝经5倍拉伸后热分解温度降低,残留量减小。     

Carbon fibers derived from wet‐spinning of equi‐component lignin/polyacrylonitrile blends

Equi‐component blends of polyacrylonitrile (PAN) and lignin, i.e., with a lignin content as large as 50 wt %, were successfully used as precursors to produce carbon fibers. Rheological measurements demonstrated that increasing lignin content in spinning solution reduced shear viscosity and normal stress, indicating a decrease of viscoelastic behavior. This was confirmed by Fourier transform infrared results that show no discernable chemical reaction or crosslinking between PAN and lignin in the solution. However, the resulting carbon fibers display a large I_D/I_G ratio (by Raman spectroscopy) indicating a larger disordered as compared to that from pure PAN. The macro‐voids in the lignin/PAN blend fibers typically generated during wet‐spinning were eliminated by adding lignin in the coagulant bath to counter‐balance the out‐diffusion of lignin. Carbon fibers resulting from lignin/PAN blends with 50 wt % lignin content displayed a tensile strength and modulus of 1.2 ± 0.1 and 130 ± 3 GPa, respectively, establishing that the equi‐component wet‐spun L/P‐based carbon fibers possessed tensile strength and modulus higher than 1 and 100 GPa. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45903.     

Effect of spinning conditions on the mechanical properties of polyacrylonitrile fibers modified with carbon nanotubes

Carbon nanotubes (CNTs) were used to modify polyacrylonitrile (PAN) polymer. The PAN/CNT composite fibers were spun from dimethylformamide solutions containing different types of CNTs. The effect of nanotube addition to the fiber precursor on the resulting mechanical properties is discussed. In this study, we examined the relationship of the rheological properties of PAN spinning solutions containing various types of CNTs and the tensile strength of the resulting PAN fibers. The presence of CNTs in the PAN spinning solution enhanced its deformability during the drawing stage. This effect resulted in a higher tensile strength in the fibers containing nanotubes, as compared to the pure fibers. The use of a three‐stage drawing process resulted in a significant increase in the tensile strength of PAN fibers modified with multiwalled nanotubes. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Structural and thermal property changes of plasticized spinning polyacrylonitrile fibers under different spinning speeds

The effect of the spinning speed on structural and thermal properties of polyacrylonitrile (PAN) fibers prepared by plasticized spinning was investigated. The PAN fibers were characterized by scanning electron microscopy, X‐ray diffraction, differential scanning calorimetry, and thermogravimetric analysis. We found that the surface morphology of the fibers was relatively smooth. The presence of a small amount of surface defects was caused by the instability of spinning process. The final fibers may have had two tensile fracture modes, that is, cluster breaking and axial split fracture. The structure of the as‐spun fibers was destroyed when the spinning speed was up to 500 m/min; this led to chain scission in the amorphous region. The final fibers exhibited mechanical properties that were roughly comparable to those of commercial PAN fibers. The changing trend in the cyclization temperature of the final fibers was consistent with that of crystallinity, which first increased and then decreased. The decomposition temperature in the amorphous region increased with increasing spinning speed. The decomposition temperature in the crystalline region increased with increasing crystallinity. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45267.     

溶解方式对聚丙烯腈-离子液体溶液和纤维的影响

通过静置、搅拌和捏合3种不同的溶解方式制备了聚丙烯腈(PAN)质量分数为13%的PAN-[BMIM]Cl(1-丁基-3-甲基咪唑氯盐)溶液。采用旋转流变仪研究了这3种溶液的流变特性,发现捏合溶解得到的溶液的零切黏度与松弛时间最小,非牛顿指数最大,溶液性质均一稳定。利用制备的纺丝溶液进行干喷湿纺试验,发现静置溶解的纺丝溶液无法纺丝,而捏合溶解的纺丝溶液可实现较高倍数的喷头拉伸和水浴拉伸。结合广角X射线衍射(WAXD)、力学性能测试、动态力学分析(DMA)等测试方法,对比分析了两种溶解方法制备的PAN纤维的超分子结构和性能,发现捏合溶解纺丝得到的纤维结构更为均匀,力学性能更好。