消防避火服用复合织物热防护效能优化研究

消防避火服作为消防员短期穿越高温明火火场实施抢救人员和重要物资行动的最高等级热防护服装,其热防护性能优劣直接决定了消防员的人身安全是否得到充分保障。从消防避火服用复合织物的结构、反射辐射热能力和隔热效能3个方面的优化方法入手,总结了国内外研究人员针对该类复合织物的研究成果,分析了复合织物防护性能优化的原理与方法,并对下一步的研究方向进行了展望。     

玻璃纤维膨体纱织物热物理性能的实验研究

玻璃纤维是现代无机非金属材料中具有独特功能的材料,其来源丰富,价格便宜,具有强度高、耐高温、耐腐蚀等一系列优异性能,使其在热防护领域发挥不可比拟的作用.为提高玻璃纤维的热防护性能,首先采用自有知识产权的连续功能纤维束气流分散法,将玻璃纤维无捻粗纱制备成玻璃纤维膨体纱、玻璃纤维膨体花式纱及玻璃纤维膨体纱织物.其次,比较、分析了不同规格的玻璃纤维膨体纱织物的外观形态、力学性能、导热系数及热防护性能.研究表明:本实验制备的玻璃纤维膨体纱织物外观丰厚,且存在较多空隙,具备良好的蓬松性和热防护性能,其中,以膨体纱作为直接纬纱制备的织物热防护性能最好,手感最丰厚蓬松,与毡类制品最接近.     

多层织物系统综合热防护性能

研究了消防服用多层织物系统的综合热防护性能.将耐高温阻燃织物Nomex、Kermel和芳砜纶织物与PTFE、TPU和三维阻燃间隔织物组合,模拟消防服的层次构成,通过垂直燃烧实验测试分析了外层织物的阻燃性能,通过TPP(热辐射和热对流综合热防护性能)实验测试分析了多层织物系统的综合热防护性能.研究得出:热防护性最大的织物组合是芳砜纶、三维阻燃间隔织物和阻燃棉布;最适宜用于消防服的织物组合是NomexⅢ A、三维阻燃间隔织物和阻燃棉布;可将三维阻燃间隔织物用于消防服结构组成中,有助于减轻消防员的热负荷.     

热辐射对消防服热防护性能及耐久性的影响

为探讨低热辐射对消防服用织物热防护性能及物理机械性能的影响,选用两种常用消防服用外层织物,利用远红外石英灯管辐射仪,以不同的辐射强度(6.5kw/m2和9.7kw/m2)对织物分别进行5、10、20、30min的辐射,利用NI虚拟仪器记录辐射时织物表面温度,并测试其各项物理机械性能及TPP值变化。结果表明:当织物表面温度低于织物纤维玻璃化温度时,织物在半小时内能保持其68.9%～84.6%的撕破强力,且TPP值增大,即热防护性能变好;而当织物表面温度达到纤维玻璃化温度时,织物断裂强力及撕破强力随辐射时间增加显著下降,但其TPP值仍增大。     

玻璃纤维空气变形纱的性能研究

为了研究玻璃纤维空气变形纱及其织物材料的特性,采用自主专利的气流吹散法制备了玻纤空气变形纱,表征其红外光谱物理特征、微观形貌、力学性能、固定树脂能力及其织物的热防护和导热性能。结果表明,玻璃纤维经高速气流分散的形纱过程为物理变化,该空气变形纱具备良好的蓬松性、固定树脂能力和力学强度,所制备的纱织物具有较低的导热系数(0.12 W/(m·K)),热防护性能较无捻粗纱提高1倍以上,TPP值为21.62cal/cm2。     

玻璃纤维膨体纱保温材料的开发及性能探讨

首先,选用玻璃纤维无捻粗纱制备了玻璃纤维膨体纱、玻璃纤维膨体花式纱及玻璃纤维膨体纱织物。其次,研究了玻璃纤维无捻粗纱和膨体纱的化学结构,并观察了它们的形态结构。最后探讨了膨体纱织物的透气性、力学性能、固定树脂能力及热防护性能。结果表明:玻璃纤维膨体纱织物外观丰厚,且存在较多空隙,具备良好的蓬松性、透气性、固定树脂能力及热防护性能。     

高硅氧纤维负载纳米Dy/TiO_2薄膜的制备及性能

为提高纳米TiO_2的光催化降解性能和稳定性,先采用微波-溶胶法制备Dy/TiO_2溶胶,再以高硅氧玻璃纤维编织体为载体,经过浸渍-提拉法制备具有高催化性能的高硅氧纤维负载纳米Dy/TiO_2薄膜。采用XRD,SEM,PL,EDS,XPS等仪器对薄膜的物相、表面形貌结构、表面元素组成及薄膜的稳定性进行表征,并且研究预处理液和涂覆方式对高硅氧纤维薄膜的影响。另外以甲基橙为目标降解物,考察样品的光催化性能。结果表明:以高硅氧玻璃纤维编织体为载体制备的Dy/TiO_2薄膜稳定性很好;经5次涂覆后,Dy/TiO_2高硅氧纤维薄膜对甲基橙的降解率在30min后达到94%。     

陶瓷/纤维/树脂超混杂复合材料的力学性能

以泡沫SiC陶瓷为基本骨架,以改性酚醛树脂为基体,加入短切高硅氧玻璃纤维制备出陶瓷/纤维/树脂超混杂复合材料(SHCM),研究了泡沫陶瓷骨架和高硅氧纤维对材料力学性能的影响.结果表明,泡沫陶瓷骨架有利于材料的刚度和尺寸稳定性提高.加入泡沫陶瓷骨架后,纤维/树脂/陶瓷超混杂复合材料的压缩强度和压缩模量增大,随着泡沫陶瓷骨架含量的提高,弯曲模量大幅度提高而弯曲强度略有下降;随着高硅氧纤维含量的提高,材料的弯曲强度及弯曲模量均明显提高.     

我国高强度玻璃纤维的研制与应用

玻璃纤维具有耐高温、抗腐蚀、强度高、吸湿性低及伸长率小等一系列优异特性,是国民经济中不可或缺的高新技术材料。自20世纪30年代末期玻璃纤维问世以来,世界各国均致力于开发具有更高性能的特种功能玻璃纤维。科研人员通过改变玻璃的化学组分与性能关系、改变玻璃纤维的截面形状、采用新的纤维成型工艺和表面处理技术等,成功研制了各种性能优异的玻璃纤维,如高强玻璃纤维、低介电常数玻璃纤维、耐高温的高硅氧玻璃纤维、异形截面玻璃纤维、轻质透波空心玻璃纤维、镀金属玻璃纤维、耐辐射和中子混合辐射的耐辐照玻璃纤维等。这些     

高新技术产品目录(新材料)(五)

序号产品名称界定条件描述《双)2《X义场铿电池玻璃纤维隔膜!比电阻70。℃,瞬时1100℃,烧失量:<5%, 纤维直径:1一3林m,纤维长度:3Inm玻璃纤维仿形织物z向间距:1.3一1.4.,体积密度:。.9一1.09/cm,《万02仪刃7仅刃20以)8臼鼠)2《双珍高纯石英纤维正交三向织物z向间距:‘Ilnm,体积密度:1.2一1.39/cm,O以)2伪10高硅氧纤维穿刺织物!z向间距2.Slnlu〕狱)2肠11机织高厚型织物由玻璃纤维、石英纤维、碳纤维和芳伦纤维等织造,用做复合材料…     

Mechanical properties of hybrid fabrics in pultruded cement composites

This work concerns the tensile properties of cement-based hybrid composites manufactured as: (i) sandwich composites that combine different layers of single fabric types; and (ii) hybrid composites, made from several yarn types within the same fabric. Hybrid combinations of low-modulus fabrics of polyethylene (PE) or polypropylene (PP) and high-modulus AR glass or aramid fabrics were prepared by the pultrusion process and tested in tension. Influence of pultrusion direction on the results was one of the parameters studied. It was found that hybrid composites made from PE and AR glass sustain strains better than 100% AR glass composites, and are stronger than a single PE fabric composite. A hybrid fabric composites made with combination of high strength–high cost aramid and low stiffness–low cost PP yarns performed better than a single aramid fabric composite relative to their reinforcing volume contents. Results show that making hybrid composites is an attractive option for cement-based elements. The performance of hybrid fabric composites is also influenced by the arrangement of fabric layers in the laminates. Composites with brittle and relatively strong fabrics (glass) at the mid-section and ductile fabrics (PE) near the surfaces of the composite performed better in tension than composites with the opposite arrangement.     

Testing and modeling of yarn pull-out in plain woven Kevlar fabrics

Yarn pull-out behavior of five styles of plain woven Kevlar fabrics, K310, K706, K720, K745 and K779 from Hexcel, was studied. These fabrics were different in fabric count, yarn size, fiber type, thickness and weight. Single yarn pull-out tests showed that the pull-out forces of the five styles of fabrics differ substantially. The yarn pull-out force was found to have positive correlation to the impact performance: fabrics with higher pull-out force performed better in impact tests. A 2D finite element model was proposed to simulate the single yarn pull-out procedure and predict the maximum pull-out force. Several factors were considered in this model: fabric count, yarn size, yarn waviness, fiber modulus, fiber diameter, cross-yarn friction, parallel-fiber friction. The predicted peak pull-out forces showed good agreement with the experimental results. Finally a simple formula was proposed to estimate the yarn pull-out force as a function of fabric count, fiber diameter, fiber modulus, yarn waviness and friction.     

The influence of carbon nanotubes on quasi-static puncture resistance and yarn pull-out behavior of shear-thickening fluids (STFs) impregnated woven fabrics

This study focuses on the puncture resistance performance of woven high modulus polypropylene (HMPP) fabric impregnated with shear-thickening fluids (STFs) composed of fumed silica nanoparticles suspended in polyethylene glycol (PEG) and those containing carbon nanotubes (CNTs). The shear-thickening characteristics and rheological features of suspensions were determined at steady and oscillatory shear stress using a stress controlled rheometer. The puncture resistance performance of STF-treated HMPP fabrics were evaluated by the quasi-static puncture test. To gain a better understanding of the effect of these two suspensions on puncture resistance mechanism of fabric, yarn pull-out test was conducted to examine internal shear strength and inter yarn frictional behavior of fabric. The results showed that both the STF-treated fabrics exhibited significant enhancement in puncture resistance performance as compared to neat fabric. However, the fabric impregnated with the suspension containing CNTs showed lower enhancement, due to its lower degree of shear-thickening as confirmed by rheological measurement. The possible improving mechanisms responsible for puncture resistance performance of STF-treated fabrics were also discussed.     

管道修复用涤纶-苎麻复合机织物性能试验

针对传统管道内衬修复材料施工中易出现内壁塌陷等问题,结合目前快速发展的绿色纤维复合材料,提出在涤纶机织物内衬材料中加入苎麻纱线,制作涤纶-苎麻复合机织物材料来提高树脂对管道修复用内衬机织物的浸透性能,增强内衬材料和管壁的粘结性能。以纤维外观、抽拔实验后纤维断面形貌的电镜观察,并通过树脂与织物接触角的测试、粘结实验,综合分析了涤-麻复合机织物的树脂浸透性,同时对涤纶-苎麻复合机织物力学性能进行测试来保障内衬复合材料满足强度的要求。实验结果表明,采用上述涤-麻复合织造的方法,可以显著提高树脂的浸透性能,有利于携带更多的树脂粘结剂提高树脂与管壁的粘结性,减少塌陷发生的可能性。同时加入麻复合的机织物,拉伸顶破性能都满足高压燃气管道的修复要求。     

三维正交机织物结构的几何模型

以经、纬纱为直线, 捆绑纱为正弦和直线组合的曲线, 建立了三维正交机织物的几何结构模型。根据捆绑纱所限定纱线的截面积, 建立了以织物结构参数为未知量的非线性方程组, 使用数值计算方法求出了非线性方程组的近似解, 确定了捆绑纱曲线模型中的待定量。制织了纬纱捆绑和经纱捆绑两种玻璃纤维三维正交机织布, 并与不饱和聚酯树脂复合, 然后观察复合材料中捆绑纱的形态, 发现捆绑纱的测试曲线与模型曲线具有很好的一致性。进一步比较捆绑纱织缩率的测试值与计算值、纤维体积含量的测试值与计算值, 表明建立的织物结构几何模型, 能够较为真实地反映三维正交机织物的实际结构。      

常压等离子处理碳纤/玻纤间隔织物的效果表征

碳/玻纤间隔织物是一种新型结构的纤维增强材料,其纤维与树脂的结合牢度是决定其复合材料性能的主要因素。为了进一步改善碳纤维和玻璃纤维与树脂的界面结合性能,本文采用不同功率的常压低温等离子技术对整体中空织物进行处理,然后通过扫描电镜、吸光率表征、玻纤单丝微脱粘测试以及碳纤维复丝拉伸性能测试等对织物中的碳纤维与玻璃纤维进行表征。研究结果表明,经过等离子处理后,混杂织物中的面层和芯材均受到等离子体刻蚀,纤维表面的官能团增多,纤维浸润性界面结合性能得到改善。同时,研究结果还表明,等离子处理碳/玻间隔织物的改性效果随着功率的增加是先增加后降低,在功率为150w的常压低温等离子处理的效果最佳。