针刺加固对耐高温过滤材料PTFE基布的影响研究

PTFE基布广泛适用在生产PTFE纤维耐高温过滤材料。本文根据耐高温过滤材料的规格,选用PTFE基布与PVA纤维网的复合方式,设计了针刺加固试验方案,观察、研究针刺后PTFE基布的性能变化,并对影响PTFE基布性能、滤料强力的针刺工艺因素进行了说明与讨论。     

基于三叶形截面刺针的针刺工艺对PTFE滤料性能的影响

通过调整三叶形截面刺针的针刺深度和针刺密度,研究了针刺工艺对聚四氟乙烯(PTFE)过滤毡的通透性能和力学性能的影响。试验结果表明:过滤毡的体积密度随着针刺深度和针刺密度的增加而逐渐增大;透气率、孔隙率和平均孔径随着针刺深度的增加而减小,随着针刺密度的增加有先减小后增大的趋势;针刺毡的纵横向强力都随针刺深度和针刺密度的增加而先增加后减小,但基布的强力随之变小;刺针对基布的损伤主要表现为PTFE长丝的纵向分裂。     

水刺加固对膜裂PTFE基布损伤性的影响

将水溶性维纶纤网和膜裂PTFE基布复合进行水刺,利用水溶性维纶在水中可溶解的性能去除表层维纶纤网,使膜裂PTFE基布从试样中分离出来,通过测试PTFE基布的强力来获取水刺后基布的损伤情况,观察水刺后基布的表观形态,并与水刺对熔纺PTFE基布的损伤和针刺加固工艺对PTFE基布的损伤进行比较。试验表明:随着水刺压力增大,膜裂PTFE基布强力损失率迅速增大,损伤以纬纱为主;表层纤网中纤维横向排列有助于降低水刺对基布的损伤;在相同水刺工艺参数下,水刺对纤维为长方形截面的膜裂PTFE基布的损伤比对纤维为圆形截面的熔纺PTFE基布的损伤大;针刺加固工艺比水刺加固工艺对膜裂PTFE基布的损伤小。     

改良型PPS除尘过滤材料的制备与性能研究

PPS(聚苯硫醚)具有强度高、耐高温、化学稳定等优良特质,是高温除尘过滤材料的理想原料,但其过滤效率较其他纤维滤材并无优势,甚至较低。为提高PPS除尘过滤材料的过滤效率,实现高效低阻,通过混入超细PPS纤维、加入PTFE(聚四氟乙烯)基布、混入PTFE纤维、PTFE乳液处理等方式,试制了改良型PPS除尘过滤材料,并对其与过滤相关的性能进行了测试。结果表明混入超细纤维可以提高滤料的过滤效率,且阻力基本不变;混入PTFE纤维后,过滤效率提高,阻力略有下降;采用PTFE乳液处理后,滤料的过滤效率明显上升,但阻力也明显增大。     

PPS/PTFE纤维复合水刺耐高温过滤材料的制备与性能研究

将PPS/PTFE纤网用水刺工艺覆盖在经过预针刺的"夹心层"结构的PPS纤网上,制得复合水刺滤料。试制了三种不同PPS/PTFE混合比的复合滤料,并测试了其基本性能和过滤性能。结果表明:PPS纤维与PTFE纤维的混合比对复合水刺滤料的性能有一定影响;该滤料具有高效率、低阻力、长寿命和耐高温等优良性能,可应用于高温除尘过滤领域;采用水刺工艺加工PPS/PTEF纤维复合耐高温滤料可以降低滤料的生产成本和提高其过滤性能。     

纬纱为Lyocell起绒基布的设计及工艺研究

机织起绒基布是制作人造革的重要材料。基布一般要求具有较高的经、纬向强力、良好的透气性、柔软的手感和良好的亲水性。通常是对机织物的纬纱进行起绒 ,起绒后 ,织物的纬向强度将大幅度下降。目前 ,用作人造革基布纬纱的纤维主要有棉、粘胶长丝、尼纶、维尼纶及涤纶等几种[1     

聚苯硫醚针刺材料的加工及其性能

聚苯硫醚(PPS)纤维制具有极佳的阻燃性、耐高温性和较好的热稳定性,耐腐蚀性仅次于聚四氟乙烯(PTFE)纤维。本文将PPS纤维通过梳理成网、针刺、后整理等工艺制成非织造材料,并对PPS高温滤料的过滤性能、耐酸性以及后整理工艺对产品性能的影响进行了分析。实验表明:PPS纤维具有一定的耐酸性,经过后整理的PPS针刺材料其过滤性能明显提高。     

防雷达侦察伪装网基布的研制

根据防雷达侦察伪装网对反射功能与穿透功能等的要求,设计、试制了伪装网的基布。基布采用金属纤维的涤棉的混纺纱,经机织而成。制得的伪装网经向雷达穿透率为10～15%,纬向雷达穿透率为5～10%。     

建筑膜材料基布各向拉伸特性的研究

对建筑膜材料基布的各向拉伸特性进行了研究。以基布的经向为基准,每偏离基准方向15°裁取一组试样,直至360°,测试各组试样的拉伸性能。实验结果表明在偏轴拉伸情况下基布的断裂强力明显减小,断裂伸长率明显增大,并且不同方向的断裂强力和伸长率具有很好的对称性,基本以基布的经、纬向为对称轴;采用抓样法测试时,试样尺寸的大小对测试结果影响不大,断裂强力和断裂伸长率都遵循相似的规律。用抓样法测试所得数据比条样法的略高,条样法的不匀率小,节省原料;抓样法的试样准备较容易和快速,并且实验状态较接近实际使用情况。     

纳米SiO2/PTFE乳液整理对聚苯硫醚滤料性能的影响

为进一步提高聚苯硫醚（PPS）耐高温过滤材料的各项性能,更好的将其应用于高温高腐蚀性环境的烟气过滤领域,本文研制了纳米SiO2/PTFE复合整理液,并应用该复合整理液对针刺PPS耐高温过滤材料进行整理试验。通过对整理后PPS耐高温过滤材料的耐磨性、孔径、过滤效率等性能进行表征,结果表明,通过PTFE乳液和纳米SiO2分散液的复合进一步改善了过滤材料的耐磨性和过滤效率等性能。在试验的基础上,得出了最佳热处理工艺：热处理温度为250℃,热处理时间150s。     

玄武岩纤维机织针织复合结构增强复合材料的拉伸性能

根据新型机织针织复合织物的结构特点,分别选用不同线密度的高强高模玄武岩纤维作为经纱、纬纱和针织纱编织织物,以其作为增强体,采用VARTM工艺制作玄武岩纤维/乙烯复合材料.为提供这种新型织物增强复合材料的应用依据,测试了复合材料的横向、纵向和斜向拉伸性能,并对各个方向的拉伸应力与应变特征曲线及其拉伸断裂形态进行分析,对比...     

亚麻/聚丙烯织物的经纬密度对其增强热塑性复合材料性能的影响

以亚麻纱线作为芯纱,PP长丝作为外包纱,利用花式捻线机纺成聚丙烯纤维/亚麻包覆纱,再织成平纹机织布,最后热压成复合材料层板。板材拉伸性能测试结果表明,随着纬纱密度的增大,经向的拉伸强度和拉伸弹性模量随之减小,而纬向的随之增大;随着经纱密度的增大,经向的拉伸强度和拉伸弹性模量也随之增大,而纬向的却随之减小。     

三维间隔织物复合材料的制备及拉伸性能研究

介绍三维间隔织物复合材料的制备方法,并采用Instron 5969型万能材料试验机对三维间隔织物复合材料的拉伸性能进行测试,重点分析间隔高度、经纬向等结构参数对三维间隔织物复合材料拉伸性能的影响。结果表明:三维间隔织物复合材料拉伸性能随间隔高度的增加而下降;纬向拉伸性能优于经向。     

7—STEELY (LOW-CRIMP,LOW-STRENGTH) AND DOGGY (LOW-CRIMP,NORMAL-STRENGTH) WOOLS—SOME NOTES ON PERFORMANCE

Steely wool has a low crimp rate and low strength and doggy wool a low crimp rate but normal strength, so that both wools are exceptionally useful experimental materials. An account is given in this paper of a comparison of the processing behaviour of wools of the two types with that of matched normal wools from yarn to fabric. The tensile properties and abrasion-resistance of the anomalous wools were as expected, but an unusual effect of the steely wool in washing shrinkage was found. The presence of steely-wool yarn in one direction (e.g., warp) caused increased shrinkage of the yam in the cross direction. Thus, in a fabric with a steely-wool warp yarn and a normal-wool weft yarn, the shrinkage index of the weft yam increased from 1.8 to 3.0; when the normal-wool yarn was used as warp with a steely-wool weft, the increase was from 1.7 to 2.4, This co-operative shrinkage did not occur with the doggy wool; it is thought to be caused by the low tensile modulus of the steely wool.     

Responses of fabric from lyocell/natural bamboo yarn to loading

With the growing demand for more comfortable, healthier and environmentally friendly products, research and development has been increasingly focusing on new environmentally friendly materials and products. One of the environmentally friendly materials is the bamboo fibre with its numerous favourable performing properties. The use of bamboo fibres increases every year, which was the main reason for choosing yarn from the mixture of lyocell fibres and natural bamboo fibres with the ratio 80/20 for the research. With the research, the tensile behaviour of woven fabrics with cotton yarn in warp and lyocell/natural bamboo yarn in the weft direction in comparison with cotton woven fabrics was studied. Twelve fabrics which differed in their construction properties were designed and produced. Two different weaves were chosen, i.e. plain and twill weave, and three different densities in weft. The results of the research show that the presence of lyocell/natural bamboo yarn in the weft direction improves the mechanical properties such as breaking stress, stress in the yield point, elasticity modulus in the weft direction of analysed fabrics, while in the warp direction, the weave type and weave density express a greater influence on the mechanical properties of analysed fabrics.     

Tensile and Frictional Properties of Wool-Cotton Union Khadi Fabrics

ABSTRACT

This paper describes the tensile and frictional behavior of wool-cotton union fabrics developed using different wool-cotton blended warp yarns, and mixed wool weft yarns spun on khadi spinning system. The tenacity and elongation at break of fabric increase with the blending of cotton with JK crossbred wool in the warp direction and high content of Australian merino wool in the weft direction, however, initial modulus decreases. The static and dynamic coefficient of friction positively correlates to the wool content in warp yarn and negatively correlates with linear density and the proportion of Australian merino wool in weft yarn.     

Warp and weft directional tensile properties of multistitched biaxial woven E-glass/polyester composites

The objective of this research work was to understand the warp and weft directional tensile properties of the two-dimensional multistitched multilayer E-glass/polyester woven composites. The warp and weft directional specific tensile strength and modulus of unstitched structure were higher than those of multistitched structures as stitching caused minor warp and weft yarn filament breakages. Contrarily, the specific tensile strains of unstitched structure were slightly lower than those of all multistitched structures. The stitching yarn type, the number of stitching directions, and the stitching density generally influenced the warp and weft directional tensile properties of multistitched E-glass/polyester woven composites. The failure of warp and weft directional multistitched woven E-glass/polyester composite structures was matrix breakages, and partial and complete yarn breakages in their surfaces. They had a local delamination in their cross-sections and the delamination did not propagate to the large areas due to multidirectional stitching. Also, the failure was confined at a narrow area and resulted in the catastrophic fiber breakages. The warp and weft directional specific damaged areas of multistitched structures, in particular four-directional stitching, were significantly lower than those of the unstitched structures. This indicated that the multistitching made the structures better damage-tolerance materials.     

基于芦山纱特征的三绞三罗织物性能分析及试织

芦山纱织物表面均匀分布稳定清晰的纱孔,呈现若隐若现的亮点而独具特色。文章对芦山纱独特的二绞二罗组织的结构进行了分析,研究了织物表面的细小纱孔和独特亮点等特征,并基于芦山纱以基础组织为地、罗组织为花的组织特征,进一步采用棉纱作经纬原料,以变化斜纹组织为地组织,三绞三罗组织为提花组织,研制了三绞三罗织物。根据不同经纬线密度的配置试织试样,对其进行织物悬垂性、折皱回复性、拉伸性能的测试。结果表明,经纬原料线密度配置与罗组织分布对织物的抗折皱性和拉伸强力具有一定的影响。     

薄型精纺毛织物综合服用性能与结构参数的关系

通过对薄型精纺毛织物经纬向拉伸强力、折皱回复角、悬垂系数、经纬向抗弯长度、织物起毛起球性能的测试,并运用Q型聚类分析方法对所测指标与织物的经纬纱线密度、经纬密度、经纬纱捻度、面密度、厚度等结构参数进行分析,得出性能指标与织物结构参数之间的关系。研究表明原料、组织相同,经纬纱线密度相近的薄型毛织物综合服用性能接近;织物的原料对薄型毛织物的服用性能影响最大;织物的面密度、厚度对薄型精纺毛织物综合服用性能影响较小。     

三原组织织物拉伸力学性能有限元仿真

为使织物在设计前就可预估其拉伸性能,对织物拉伸过程进行了有限元模拟和试验验证。通过超景深数码显微镜对织物试样的细观照片进行尺寸测量,得到纱线的几何结构参数,借助AutoCAD绘图软件建立了三原织物单胞物理模型;基于纱线拉伸试验和织物周期边界条件理论,利用有限元分析软件ANSYS研究了三原织物的拉伸性能;并将有限元仿真结果与拉伸试验结果进行对比。结果表明：织物经向拉伸时,经向平均应力、经向平均应变、纬向平均应变和泊松比的有限元模拟结果与试验结果的差异均在5%左右;经向弹性模量的有限元模拟结果与试验结果的差异也在10%以内;证明有限元仿真的可行性。