聚苯硫醚纤维的研究现状与应用

聚苯硫醚纤维作为高性能纤维,近年来的研究逐渐成为热点。介绍了聚苯硫醚纤维的性能、国内外相关研究成果及应用领域,以期对聚苯硫醚纤维的研究提供相关指导。     

天然帽用草纤维的形态结构及EDS能谱分析

对蓆草、棕丝草、琅琊草、咸草、蒲草等5种帽用草纤维用扫描电镜观察其表面形态和截面结构,发现帽用纤维表面存在大量的气孔和沟槽,测量出气孔的长度20-73μm,宽度8-33μm。截面有较大的空隙,纤维空隙的大小依次是棕丝草、蒲草、琅琊草、蓆草、咸草。对其表面选取微区进行EDS能谱分析,结果表明5种帽用草纤维都含有C、O、Al,且C、O元素的含量都在96.99%以上,其他如Si、Na、Mg、Cl、P等属于微量元素,属纤维素纤维。     

SiO2/TiO2共混电纺纤维的制备及光催化性能研究

以正硅酸乙酯(TEOS)和钛酸四丁酯(Ti(OC4H9)4)为原料,采用静电纺丝技术制备了SiO2/TiO2共混纤维膜,经过煅烧后得到了SiO2/TiO2无机纳米纤维.采用TG-DTA对SiO2/TiO2共混无机纤维的热行为进行了表征,并对不同电压、不同纺丝液配比以及不同煅烧温度条件下得到的样品进行了SEM表征,研究不同条件对纤维形貌和光催化性能的影响.结果表明:当纺丝电压+17 kV、接收距离13.5 cm时,纺丝液最佳配比是4.0 g PVP、11 mL EtOH、1.0 mL HAc、1.3 mL TEOS和1.0 mL Ti(OC4H9)4.为了得到形貌和组成兼备的SiO2/TiO2共混无机纤维,确定最佳热处理条件是450℃保温3 h,样品在紫外光照射下对亚甲基蓝的最高去除率达到51%.     

低干缩延性材料-混凝土复合梁抗弯性能

为研究延性材料对普通混凝土的增强增韧效果,本文采用低干缩高延性纤维增强水泥基复合材料(LSECC)与普通混凝土复合的方式,从试验与模拟两个方面研究了复合梁的抗弯性能．结果表明,在梁底复合低干缩延性材料后不仅可以提高梁的抗弯承载能力,还大幅提升了梁的延性．当LSECC的强度比上层混凝土的强度高时,复合梁的峰值荷载受LSECC层厚的影响明显,随着层厚的增加而增大．当上层混凝土的强度较高时,复合梁的峰值荷载随LSECC层厚度的变化不明显．基于开裂强度和材料应力裂纹宽度关系的抗弯模型可良好地预测不同材料复合梁的弯曲性能,模型结果与实测值吻合良好,可用于组合结构优化设计．     

Analysis and characterization of orientation structure of pre-oxidized PAN fibers in high magnetic fields

PAN fibers pre-oxidized at 240 ℃, 260 ℃, 280 ℃, 300 ℃ were treated in 8 T, 12 T, 16 T high magnetic fields, respectively. The experimental result implied that there were two kinds of magnetic units cyan and carbon-nitrogen heterocycle in pre-oxidized PAN fibers, and the movement of magnetic units resulted in changes of orientation structure of pre-oxidized PAN fibers in high magnetic fields. Overall orientation increased with increase of magnetic field intensity and extension of processing time, whereas change of crystalline orientation depended on magnetic field intensity and content of carbon-nitrogen heterocycle due to the competition of two magnetic units. Furthermore, magnetic fields induced the conversion from amorphous region to crystal region and improved crystalline properties of pre-oxidized PAN fibers.     

Enhanced healing of full-thickness diabetic wounds using bioactive glass and Yunnan baiyao ointments

In order to accelerate the chronic wounds healing, we investigated the healing effects of bioactive glass and Yuunan baiyao ointments in streptozotocin-induced diabetic rats. The ointments were prepared by mixing 45S5 bioactive glass powder （16% weight） with Vaseline and different weight percentages of Yurman baiyao. Full-thickness defect wounds were created on the back of 130 SD rats and were randomly divided into 8 groups. The wound healing rates were calculated at 4, 7, 10, 14 and 21 days after surgery. The samples were harvested for further observations. Considering the wound closure rate, group 6 （with 5% Yuunan baiyao） has better wound healing performance than other diabetic groups. The lower inflammatory response was observed by gross observation and confirmed by the results of H＆E staining and TEM observation. Besides, the proliferation of fibroblasts, the formation of granulation tissue, as well as the vascularization, were improved in group 6 compared to other diabetic groups. All results suggest that bioactive glass and Yunnan baiyao ointments can accelerate the recovery of diabetes-impaired skin wounds, and comparing to other diabetic groups, group 6 （with 5% Yunnan baiyao） has better healing effect.     

废旧棉纺织品机械拉毛法回收纤维实验研究

废旧纺织品回收再利用是解决全球环境和资源问题的一种方法,机械拉毛法回收再利用废旧纺织品是使回收和再生变为现实的一种简单可行的方法.自制拉毛简易装置,经实验研究发现,在对废旧棉纺织品使用拉毛法回收纤维时,其排列间隔、钉子露出长度和钉子尺寸等对拉毛效果有一定的影响.     

氯化锂对纤维素/离子液体浓溶液纺丝的影响

以离子液体1-烯丙基-3-甲基咪唑氯盐（[AMIM]Cl）为溶剂、氯化锂（LiCl）为添加剂,通过测定纤维素溶液的流变性能来考察LiCl对纤维素/[AMIM]Cl溶液纺丝性能的影响,发现纤维素/[AMIM]Cl/LiCl呈现切力变稀行为,当LiCl添加量为[AMIM]Cl质量的3%时,切力变稀行为最明显.使用双螺杆挤出机通过干湿法纺丝制备出了高浓度的纤维素纤维,通过XRD、偏光显微镜、SEM及单纤强力仪等表征了纤维的结构与性能,结果表明随着LiCl含量的增加,所得纤维的结晶度和双折射率增加,结构致密,纤维强度增加,当LiCl含量达3%时,纤维强度可达3.13 cN/dtex.     

麻赛尔/涤纶交织针织物服用性能的研究

根据麻赛尔纱线的特点,利用其与涤纶交织开发针织面料,对麻赛尔/涤纶交织针织物的透气性、透湿性、水洗尺寸变化、起毛起球性、硬挺度以及顶破强力进行了测试和分析,并利用模糊综合评价系统对3种试样的服用性能作了综合评价,结果显示麻赛尔与涤纶合理地进行交织时具有较好的服用性能.     

咖啡纤维结构与性能研究

介绍了咖啡纤维的生产过程和物理性能,通过红外光谱仪、X射线粉末衍射仪和扫描电子显微镜研究了咖啡纤维的亲水基团、吸湿性、结晶度和形态结构等,并与棉纤维和麻纤维进行了对比,证明了咖啡纤维的可纺性,有利于咖啡纤维的进一步开发和利用.