A Study on the Surface Structures of Viscose-based Activated Carbon Fiber by FT-IR Spectroscopy and XPS

Using viscose fiber (VF) as starting material and common steam as activating agent, formation of oxygen structures in activated carbon fiber is investigated. In the preparation of samples, VF was first heated at temperatures between 450℃ and 900℃ in N_2 artmosphere. Then, in a successive activation stage, the product carbonized at 600℃ was activated in steam at 450-900℃ for 30 min, and at 600℃ for 5-30 min. The other carbonization products were activated at 600 and 900℃ for 30 min respectively. The products activated at 900℃ were then activated at 450℃ for 30 min again. The starting materiah carbonized products and all activation products were examined by FT-IR spectroscopy and some products were examined by X-ray photoelectron spectroscope (XPS). And the yields of the carbonized and activated products were calculated. By analysing these spectra, the amount of oxygen-containing functional groups of the activated products attained under various activation time, various activation temperature and various previous carbonization temperature was determined.

Identification of Bamboo Viscose Fibers and Conventional Viscose Fibers

Bamboo viscose fibers and conventional viscose fibers were measured by optical microscopy, scanning electron microscopy (SEM), Fourier transform infrared spectrometer (FTIR), and thermogravimetric analyzer/FTIR spectrometer (TG-FTIR) respectively. At last, the method based on the testing of the Fourier transform near infrared (NIR) spectra was proposed to identify these two kinds of fibers. The discrimination models between bamboo viscose fibers with conventional viscose fibers were built by means of Ward's algorithm and Hierarchical cluster analysis(HCA) after the first derivative and vector normalization pretreatment, and were verified finally. The results indicate that these two kinds of fibers are similar in their morphology both of cross-section and longitudinal direction. What's more, the FTIR spectra, the thermostability, and decomposition products of TG-FTIR experiment are similar, and the testing results contribute little to the effective identification of the two fibers. However, the accuracy of the NIR spectra model is high, and the two kinds of fibers can be classified into two separated groups to achieve the identification simply and exactly.

STUDY ON POLYPYRROLE-VISCOSE CONDUCTING FIBER

The conductivity of Polypyrrole-viscose conducting fiber prepared with author’s method can be shown up to as high as 2.106x10-2 S/cm. The main factors influencing the conductivity are the concentration of FeCl3 used as dopant and initiator, the treatment time of viscose fiber as base material in FeCl3 solution, temperature and polymerization time. It is found that the orientation and crystallization degree of viscose fiber keep constant before and after conducting treatment and the mechanical properties of conducting fiber is the same as that of base material. In addition, the distribution of polypyrrole in viscose fiber, and its effect on the conductivity were investigated in details by TEM.

Comparison between the Direct Dyeing Kinetics of Bamboo and Conventional Viscose Fibers

Two direct dyes were applied to conventional viscose(CV)and bamboo viscose(BV)fibers,which were prepared from bamboo cellulose pulps,and the dyeing kinetics of two fibers were compared.Three kinetic equations,namely Chrastil,Cegarra-Puente,and Vickerstaff,were used to fit the experimental dyeing rate points,showing that the best result was obtained by the Chrastil equation.BV fibers displayed slightly higher dyeing rates and dye adsorption values at initial stages,but a bit lower dye adsorption values at equilibrium than CV fibers.Furthermore,the dyeing of BV fibers exhibited lower activation energies and higher dyeing rate constants than that of CV fibers,and therefore showed slightly lower dependence on temperature.

Research on Thermal Properties of Nomex Fiber and Nomex/Viscose Blended Fabric

Based on the analysis of the properties of Nomex 450 and Nomex 462,the thermal properties of Nomex 462/Lenzing Viscose Flame retardent(FR)blending materials were analyzed.It was discovered through burning test and Thermal Gravity(TG)analysis that the blended material was superior in thermal behaviors to the material made from either Nomex or Viscose FR filament,when the ratio of Nomex and Lenzing Viscose FR reached 80∶20,and excellent thermal properties were achieved with the value of Limiting Oxygen Index(LOI)up to 36.1%.Blending Nomex and Viscose FR filaments may be recommended for better fire retardant property of related fabric.

Kermel/Viscose FR混纺阻燃织物的开发

采用Kermel纤维和阻燃粘胶纤维ViscoseFR ,以不同的比例进行混纺 ,试制成了耐热阻燃织物。将各种混纺比织物进行了性能测试比较 。

A fiber-array probe technique for measuring the viscosity of a substance under shock compression

A fiber-array probe is designed to measure the damping behavior of a small perturbed shock wave in an opaque substance, by which the effective viscosity of substance under the condition of high temperature and high pressure can be constrained according to the flyer-impact technique. It shows that the measurement precision of the shock arrival time by using this technique is within 2 ns. To easily compare with the results given by electrical pin technique, the newly developed method is used to investigate the effective viscosity of aluminum （Al）. The shear viscosity coefficient of A1 is determined to be 1700 Pa.s at 71 GPa with a strain rate of 3.6× 10^6 s-1, which is in good agreement with the results of other methods. The advantage of the new technique over the electrical pin one is that it is applicable for studying the non-conductive substances.

Property of Polyimide/Flame-Retardant Viscose Blended Fabrics

Although polyimide fibers are excellent intrinsic flame-retardant fibers, their price is so high that they are rarely used in clothing. To expand their application, the polyimide fibers were blended with flame-retardant viscose fibers at a ratio of 30∶70, and the blended yarns were woven with flame-retardant polyester filaments. Fabrics with different parameters, including fabric weaves, warp yarn densities, and fabric layers, were designed, and the effects of those fabric parameters on mechanical properties and flame-retardant properties were tested and analyzed. The results show that the tearing load of the fabrics is affected by fabric weaves, warp yarn densities, and fabric layers, and the tearing load of the weft mountain weave fabric and the twill weave fabric is higher than that of the plain weave fabric. The bursting load of the fabric increases with the increase of warp yarn densities and layers. Among the tested fabric samples, the triple-layer twill fabric has the best flame-retardant performance, which meets the standard of flame-retardant protective fabric Grade B1 level. The research of this paper would provide guidance for the development and production of polyimide blended fabrics.

About Viscosity of Cotton Fiber

The biological variety is mainly connected with presence of the field ecosites,which determine the mechanism of interaction(the symbiosis,pathogenesis,and etc.) that differ typically of such

色纺纱用黏胶纤维的连续染色工艺与染色性能

采用散纤维连续染色技术对黏胶散纤维进行连续浸渍染色后再冷堆固色,然后进行连续式水洗。分析了固色时间对黏胶纤维外观形貌、色泽指标及力学性能的影响,并对染色黏胶纤维成品的色牢度、pH和甲醛含量进行测试。结果表明:连续浸渍染色后的黏胶纤维,经冷堆24 h固色后,可获得较好的匀染性;染色黏胶纤维的力学性能略有下降,其中强度下降约15%,断裂伸长率下降约16%;染色黏胶纤维的各项色牢度、pH和甲醛含量均符合要求。

喷气涡流纺长片段竹节段彩纱的设计与生产

探讨有色超短纤维在喷气涡流纺花式纱开发中的应用及生产要点。采用有色粘胶超短纤维与本色竹浆纤维、椰炭改性涤纶纤维,在并条机上加装竹节装置,利用喷气涡流纺纱技术纺制成长片段竹节段彩纱。针对粘胶纤维长度相对较短的特点,工艺上尝试采用短流程、减小隔距、降低打击件速度等技术措施。结果表明:开发的喷气涡流纺段彩纱具有段彩片段长、生产效率高的特点,其在布面上色点朦胧,时而形成连续分布,时而散点分布,形成不同于传统段彩纱的独特风格。

阻燃纤维/不锈钢纤维混纺纱线的力学性能分析

为探讨混纺比对纱线性能的影响,测试分析了5种不同混纺比的阻燃腈纶(A)/阻燃黏胶(R)/不锈钢纤维(G)(A90/G10、A70/R20/G10、A45/R45/G10、A20/R70/G10、R90/G10)混纺纱线的力学性能。结果表明:混纺纱线的拉伸断裂性能、弹性、蠕变性能、耐磨性能、扭转性能和弯曲性能随阻燃腈纶纤维混纺比的增加而提升;A45/R45/G10混纺纱线的疲劳性能较差,A90/G10混纺纱线的疲劳性能较好;在较大压力下,A70/R20/G10和R90/G10混纺纱线的压缩性能较好,在较小压力下,A20/R70/G10混纺纱线的压缩性能较好。

涤纶/黏胶纤维复合针刺非织造布的制备及疏水整理

以聚酯纤维和黏胶纤维为原料,混合成网后通过针刺工艺制备具有多孔隙的三维结构的涤纶/黏胶纤维复合针刺非织造布;然后,选用氟化后的纳米SiO_(2)颗粒和SiC颗粒对非织造布进行表面进行疏水整理,并对试样的克重及厚度、化学结构、微观形貌、机械力学性能、疏水性能等进行研究,分析原料配比对产品各项性能的影响。结果表明:纤维表面富含大量的纳米SiO_(2)颗粒和SiC颗粒,且适当提高涤纶纤维的含量,可改善试样的机械力学性能和疏水性能。基于以上良好的性能,涤纶/黏胶纤维复合针刺非织造布可用于防水领域。

谷物膳食纤维减缓淀粉消化性的机制研究进展

淀粉和膳食纤维同为谷物中重要的营养物质,均有益于人体健康。淀粉的消化速率和消化率是影响人体餐后血糖的关键因素,膳食纤维是一种不易被肠道吸收的营养素,因具有减缓淀粉消化的能力,近年来深受关注。本文综述了国内外关于谷物膳食纤维对淀粉消化性的影响,并从膳食纤维的黏度降低淀粉分解动力学、延迟胃排空和膳食纤维对淀粉的物理包埋以及完整细胞壁对淀粉的包裹这三个方面归纳总结了其减缓淀粉消化性的作用机制,为后续低血糖生成指数食品的创制提供理论依据。

树脂黏度对碳纤维与环氧树脂浸润性及界面结合性能的影响

碳纤维与环氧树脂基体形成良好的界面结合是发挥复合材料基本性能的保障,考察3种国产T700级碳纤维,研究树脂黏度对碳纤维浸润性以及界面结合性能的影响。结果表明:由室温升到60℃,树脂体系黏度从1401.9mPa·s降低到102.77mPa·s,碳纤维与树脂的接触角减小,浸润能力增强,从而提高复合材料的界面结合强度,在60℃下制备的复合材料层间剪切强度提高了17.44%。同时纤维表面的沟槽结构能够加强物理机械互锁作用,加强复合材料的界面结合强度。

有色抗菌护肤远红外黏胶纤维制备及性能研究

将金缕梅提取物10.0份、植物色素1.7份制成浓度为20%的水溶液,胶原蛋白肽8.4份配成50%的水溶液,远红外陶瓷粉3.3份配成浓度为20%的悬浮液,按总添加质量为甲纤质量的14%与黏胶纺丝液共混,采用湿法纺丝方法制备线密度为1.67dtex、长度为38mm、颜色为樱花粉和柠檬黄的有色抗菌护肤远红外黏胶纤维。对纤维性能和功能进行测试,结果表明,有色抗菌护肤远红外黏胶纤维对金黄色葡萄球菌的抑菌率为87.25%、蛋白质含量为3.77%远红外发射率和温升分别为0.86和1.90℃,性能超过国家和行业标准。纤维纵向和横向形态无显著变化,红外特性、结晶度、取向度、力学性能均能满足后续纺纱织造要求。

功能性水刺粘胶纤维膜/UiO-66-NH_(2)的制备及其对Cr(Ⅵ)的吸附性能研究

金属有机骨架材料UiO-66-NH_(2)在水中呈粉末状难以回收,水刺粘胶纤维表面含有大量的羟基,具有良好的亲水性且可工业化大规模生产。因此,通过原位生长法将UiO-66-NH_(2)均匀生长在水刺粘胶纤维表面,制备出UiO-66-NH_(2)/水刺粘胶复合纤维膜。SEM、FT-IR、BET和XRD表明,水刺粘胶纤维表面上均匀生长了UiO-66-NH_(2)。此外,探究了pH、吸附时间、吸附剂用量、Cr(Ⅵ)浓度对改复合纤维膜吸附性能的影响。最佳条件下,其最大吸附量为129.37mg/g;当pH=1时,经过4次的循环吸附后,其对Cr(Ⅵ)的去除率从100%下降到76%,证明其具有良好的循环使用性能。UiO-66-NH_(2)/水刺粘胶复合纤维膜对Cr(Ⅵ)的化学吸附过程符合准二级动力学模型和Langmuir等温吸附模型。

植物复合香味防螨黏胶纤维制备及性能研究

将甜橙精油、薰衣草精油、桔子精油按照5.0∶1.5∶1.0混合后制成复合香味精油微胶囊,艾草提取物和白鲜皮提取物按质量比为3.0∶2.0制成20%水溶液,复合香味精油微胶囊添加量占纺丝液总体积2%,提取物水溶液按总的质量为纺丝液中甲纤质量的10%添加与黏胶纺丝液共混,采用湿法纺丝方法制备线密度为1.67 dtex、长度为38 mm的植物中药复合香味防螨黏胶纤维,并对其性能和功能进行测试。结果表明:植物中药复合香味防螨黏胶纤维的结晶度、力学性能均能满足后续纺纱织造对纤维的要求;功能纤维香味浓郁,经12次洗涤后,留香率为27.30%,螨虫驱避率为73.53%,该功能纤维在针织服装、针织床品等方面具有较大市场前景。

铜氨络合粘胶纤维的制备及其抗菌性能

利用铜氨溶液对粘胶纤维进行处理,制备了铜氨络合粘胶纤维。分析了铜氨溶液浓度、反应时间对Cu^(2+)结合量的影响。通过SEM、XRD和XPS表征了粘胶纤维的形貌与化学结构,测试了不同Cu^(2+)结合量下铜氨络合粘胶纤维的抑菌性及耐水洗性能。结果表明:随着铜氨溶液浓度的提高,Cu^(2+)结合量迅速增加;当溶液浓度达到25.00 mmol/L时,Cu^(2+)结合量达到最大值;反应30 min,即可达到络合平衡。铜氨溶液处理后,Cu^(2+)与粘胶纤维的羟基发生配位络合反应,纤维纵向分布着络合物小颗粒,形貌变粗糙,横向截面变化较小;纤维化学结构无明显改变。铜氨络合粘胶纤维显示出较好的抗菌性能,当铜氨溶液浓度达到0.30 mmol/L时,对大肠埃希菌和金黄葡萄球菌的抑菌率分别为97.80%和99.33%,经50次标准水洗后,抑菌率分别为83.40%和86.51%。

高黏改性玄武岩纤维开级配沥青混合料性能研究

为改善开级配沥青路面路用性能,选用HVA-H高黏剂及玄武岩矿物纤维对OGFC-13沥青混合料进行复合改性。并引入HVA型、SEBS型两种高黏剂作为对比,评价HVA-H高黏剂对SBS改性沥青及OGFC-13沥青混合料性能的改善效果。通过配合比设计,确定HVA-H、HVA、SEBS掺量均为8%,玄武岩纤维掺量均为0.4%时混合料的最佳油石比。通过对沥青混合料开展相关路用性能试验,评价三种高黏剂对OGFC-13沥青混合料性能的影响。结果表明:HVA-H型高黏剂对沥青的高低温性能改善效果最优,HVA-H高黏改性沥青对矿料的黏结能力最强;HVA-H高黏剂对OGFC-13沥青混合料高温抗车辙、低温抗开裂及抗水损害能力的改善效果显著优于HVA型、SEBS型两种高黏剂。