VARIATION OF WOVEN FABRIC GEOMETRY——Non-uniform Flattening of Yarns

In previous research much effort has been devoted to the geometry of woven fabrics and relat-ed problems under the assumption of constant yarn configuration in fabric.This paper will first re-port that image crimp (yarn crimp measured by an image analysis method) seems larger than actualvalue.From the explanation of this result,the variation of yarn configuration in woven fabric dueto the non-uniform flattening is revealed.The significance of this actual structure of woven fabricsis discussed.It is believed that the variation of yarn configuration is very important for fabric per-formance,and may be an advantage for fabric quality.

Comparative Study of Polypropylene Non-Woven Surgical Mask and Locally Manufactured Woven and Knitted Fabrics Facial Masks

The outbreak of coronavirus has led to an increase in the demand for facemasks globally. Unavailability of appropriate polypropylene non-woven fabrics face masks as a result of inadequate supply to satisfy the growing population has brought about the manufacturing of locally fabrics masks to augment or substitute standard medical class facemasks. The study aims at analyzing airflow of these locally manufactured fabrics to determine possible means of transmitting the virus as well as establish comfort of the user of these masks. Standard polypropylene non-woven, woven and knitted fabrics were considered for the study. Air permeability test was conducted on these fabrics using Frazier Air permeability tester. Depending on the property significant variation in the textile fabrics, polypropylene non-woven is widely accepted for facial masks. Nevertheless, this study illustrates that woven and knitted fabrics have more open structures, which allow a high rate of air penetration and so may require two or three layers to prevent antimicrobial or antiviral potential.

Preparation of UV-curable Nano-silver Antimicrobial Agent and Its Application in Non-woven Fabric

Nano-silver and waterborne polyurethane(WPU)composite emulsion was synthesized.The average diameter of silver nanoparticles(SNPs)was about 20 nm,and the average diameter of WPU was 101.32 nm.The anti-bacteria finishing of a polypropylene non-woven fabric(NWF)was carried out by ultraviolet finishing technology and the double dipping twin-roll method.The standard AATCC100 was used to test the antimicrobial activity of the samples.The results showed that the antimicrobial rates of Klebsiella pneumoniae(K.pneumoniae)and Staphylococcus aureus(S.aureus)were above 90%,which indicated that the NWF finishing had good antimicrobial activity.In addition,the thermal stability,mechanical properties,whiteness and contact angle of antimicrobial finishing nonwovens were characterized.The results showed that the performance of antimicrobial nonwovens was stable at 300℃.The breaking strength was better than that of untreated nonwovens,and the contact angle reached 119.1°.

“无机粒子-无纺布”协同改性碳纤维复合材料及其增韧机理

针对碳纤维复合材料层间性能较差、易发生分层损伤的问题,提出一种采用SiC粒子和热塑性共聚酰胺(PA)无纺布对碳纤维/环氧树脂基复合材料(CFRP)进行增韧改性的技术,在层间构筑一种“无机颗粒/热塑性纤维/树脂基体”多组分多尺度增韧相体系,对比分析改性前后复合材料的Ⅰ型、Ⅱ型层间断裂韧性和耐热性,借助扫描电子显微镜(SEM)和动态热机械分析仪揭示其增韧和耐热性机制。结果表明,与未改性的CFRP材料相比,当SiC填充量(质量分数)为1%、PA无纺布面密度为25 g/m2时,改性CFRP材料Ⅰ型层间断裂韧性(GⅠC)和Ⅱ型层间断裂韧性(GⅡC)分别提高了52.7%和222.6%。无机粒子的阻滞效应、纤维的桥连效应和基体树脂的塑性变形是其主要增韧机制。

GN-g-MAH/PPy多功能PET非织造布的制备及应用

为提高聚酯(PET)非织造布的性能,将导电材料通过表面改性引入PET非织造布,采用单宁酸(TA)作为桥联剂,功能化石墨烯(GN-g-MAH)和聚吡咯(PPy)作为导电功能层,制备得到多功能PET非织造布,并使用SEM、XRD、TG等测试了PET/GN-g-MAH/PPy的微观结构和热稳定性。结果表明:通过循环自组装法及低温化学聚合法成功制备了PET/GN-g-MAH/PPy非织造布,表现出良好的导电性,表面电阻率低至3.11×10^(-2)Ω·m,表面由疏水转变为亲水。基于此,非织造布也表现出优异的电热性能,对其施加3 V驱动电压时,可在20s内产生约40℃的饱和温度。此外,还具有良好的光热转换性能,当光照强度为300 mW/cm^(2)时,照射20 s后,表面温度可稳定到105.8℃,非织造布还表现出优异的光热抗菌性,当大肠杆菌的菌液浓度为1.6×10^(8)CFU/mL时,使用氙灯模拟太阳光源照射后,抗菌率达到99.6%。

A STUDY OF THE SPECIMEN SIZE OF STRIP TENSILE TEST FOR NEEDLE-PUNCHED NON-WOVEN GEOTEXTILES

In this paper,the failure features of strip tensile specimen were observed and analysed for need-le-punched non-woven geotextiles.A mechanical model which expresses the relation between thetensile modulus,the strip specimen size,contraction factor and the tensile strength of non-wovenfabric was derived.The theoretical prediction showed that the main factor influencing tensilestrength of non-woven geotextile specimens with different size is the contraction factor of specimenor the specimen aspect ratio(width/length).The larger the aspect ratio,the higher the tensilestrength test value of geotextiles,but the experiments showed that the specimen tensile strength isnot increased with increasing the width of specimen.The reason was discussed and it seemed thatthe deviation could be served as an indication of the degree of imperfectness of the non-wovenstructure.

Relationships between the Processing Parameters of Melt Blown Nonwoven Fabric and Its Structure and Filtration Property

Based on the processing experiment and sodium flame test this paper deals with the relationship between processing parameters, structure, and filtration property of melt blown fabric. Through the image analysis of Questar micro-images in combination with the SEM observation and the measurement of some macrostructure indices, the relationship between the processing parameters and the structure especially the microstructure is emphasized Finally the effect of somestructure factors on filtration properties is discussed theoretically.

Turbulent Flow Action of Pulp in Wet - Laid Non - Woven Processes

The paper deals with the fluid field of web forming in wet-laid non-woven production.The influence of the turbulent flow on blending fiber and occluded fluid produced in pulp flow has been discussed in theory and practice.The suitable use of the imported velocity of pulp is very important in producing wet-laid products of good quality.

预辐射接枝包埋法制备NWF-g-DMC@Al_(2)O_(3)吸附剂及其对亚氯酸盐的去除

亚氯酸盐等消毒副产物,已经被国际癌症研究中心列为致癌物,对其进行有效的处理,成为饮用水净化过程中的当务之急。本文以水为溶剂,通过预辐射接枝包埋反应,成功合成了系列无纺布-甲基丙烯酸乙酯基三甲基氯化铵-纳米三氧化二铝(NWF-g-DMC@Al_(2)O_(3))吸附材料,并系统探讨了吸收剂量、单体浓度等多种因素对增重率的影响,进而探讨不同增重率、包埋率、溶液pH对吸附率的影响,获得了完整的静态吸附平衡曲线。利用红外光谱仪(IR)、扫描电镜(SEM)、热重分析仪(TG)、X射线衍射仪(XRD)、水质分析仪等表征手段对该制得的样品的结构与吸附性能等进行表征与测试。结果表明:单体浓度为40%时,增重率最大。吸收剂量为100 kGy、包埋量为4%、pH为2、初始浓度为10 mg/L时的吸附率最高,NWF-g-DMC@Al_(2)O_(3)吸附剂对消毒剂副产物亚氯酸盐的脱除率高达89%。该吸附剂有望在饮用水、工业用水领域得到广泛的应用。

On the Representation of Multi-layer Woven Structure

A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the reinforcement of textile composites, the relationships among the structural parameters are derived for different binding patterns of the fabric structure. The conditions, which meet the requirements of structural cell stability,are also discussed.

多色无纺布包装材料在手术器械灭菌管理中的应用效果

目的:分析多色无纺布包装材料在手术器械灭菌管理对手术周转效率、手术器械准备情况及外科医护人员与患者满意度等影响。方法:选取2016年3月至2021年12月首都医科大学附属北京友谊医院消毒供应中心的31589件手术器械,根据管理方法不同,将2016年3月至2019年1月的71007例手术患者及患者使用的16224件手术器械纳入对照组,采用传统的纱棉布包包装手术器械管理方法。将2019年2月至2021年12月的62548例手术患者及患者使用的15365件手术器械纳入观察组,采用多色无纺布包装材料手术器械管理方法,比较两组手术周转效率、手术器械准备情况及患者与外科医护人员的使用管理满意度。结果:观察组患者手术的入室时间、入室-切皮时间、接台手术入室-切皮时间及手术延误率均低于对照组,差异有统计学意义(t=52.681、37.167、72.524,χ^(2)=9.605,P<0.05)。与对照组比较,观察组外出送物品次数、装配错误和器械丢失明显降低,器械完好件数明显提高,差异有统计学意义(χ^(2)=107.345、11.782、8.727、66.223,P<0.05);观察组患者及医护人员器械使用管理的满意度显著高于对照组,差异有统计学意义(t=100.723、6.756,P<0.05)。结论:手术器械运用多色无纺布包装材料有助于提高手术周转率,通过降低外出送物品次数、装配错误及器械丢失提高消毒供应中心工作效率,改善外科医护人员与患者对手术器械多色无纺布包装材料的满意度。

纯棉无纺布低温近中性练漂体系构建及其工艺优化

纯棉无纺布练漂在高温强碱中进行,能耗高、排污大、纤维损伤严重。针对该问题,试验构建了三种低温近中性练漂体系,通过对比三者练漂无纺布的颜色特征值、亲水性能和机械性能,选出最优体系;采用XRD、FT-IR、SEM分析体系对棉纤维微观结构与形貌的影响;通过中心复合设计(CCD)优化该体系漂白工艺,并寻求影响织物白度(WI)的关键因素。研究表明:四乙酰乙二胺/过氧化氢(TAED/H2O2)体系练漂织物WI最高,亲水性优良,强力损伤最小(<20%);练漂体系对棉纤维晶型结构与官能团无影响,能有效去除纤维表面杂质,保护纤维不受损伤。CCD结果显示,温度对WI影响最显著,其次是H2O2浓度与NaHCO3浓度;在最优条件下,得到的理论最优WI为90.38,比原布WI高39.32%。

超吸水织物的制备及性能研究

以丙烯酸为单体,过硫酸钾、亚硫酸氢钠为氧化还原引发剂,与聚乙烯醇共混,采用溶液聚合法制备了丙烯酸高聚物溶液,浸轧丙纶热熔无纺布织物,经烘干得到超吸水织物,通过傅里叶变换红外光谱仪、场发射扫描电子显微镜、同步热分析仪对超吸水织物的结构、形貌和热性能进行分析,考察了聚合反应水浴温度、丙烯酸中和度、聚乙烯醇添加量、带液率对吸水倍率的影响,并对吸水机理进行探讨。结果表明:在聚合反应水浴温度为75℃,丙烯酸中和度75%,聚乙烯醇添加量(对单体)为5%(质量分数),带液率为500%,烘干温度为120℃条件下,制备的超吸水织物吸蒸馏水倍率为109.82g/g。

PA6/PE基体-微纤型纤维溶解抽出过程的研究

对浸胶的 PA6/PE(60 /4 0 )共混纤维无纺布试样用二甲苯进行溶解抽出 ,计算其 PE的溶出率(抽出率 ) ,探索渗透剂氨基硅烷对溶解过程的影响。结果表明 :溶解抽出的温度高于 70℃ ,并且温度越高 ,溶解时间越长 ,PE的抽出率越大 ,最佳溶解温度为 85～ 90℃ ,溶解时间为 60～ 90 min;溶解过程中在二甲苯中加入适量浓度的氨基硅烷对 PE的溶解抽出有一定的促进作用 ,还可以使无纺布更加柔软 ,手感更好。

超疏水亲油PDMS@mSiO_(2)-PP非织造布的制备及其油水分离性能

为了制备一种超疏水亲油的材料,通过硅烷偶联剂KH560对纳米二氧化硅进行改性,再将改性纳米二氧化硅(mSiO_(2))和低表面能的聚二甲基硅氧烷(PDMS)后处理聚丙烯(PP)熔喷非织造布,制备了一种绿色无污染超疏水亲油材料,并采用扫描电子显微镜、红外光谱仪、马尔文激光粒度仪、接触角测试仪、万能拉伸仪和油水分离等对超疏水亲油材料的结构及性能进行表征。结果表明:制得的超疏水亲油PDMS@mSiO_(2)-PP材料具有良好的力学性能;同时该材料的静态接触角最高达155.89°,对食用油、机油和石蜡油的最大吸油倍率分别为40.21 g/g、33.96 g/g和33.68 g/g,能够快速分离油水混合物,具备优异的超疏水性亲油性能。

PP无纺布预辐射法固相接枝4-VP的研究

以预辐射聚丙烯无纺布为基材,4-乙烯基吡啶为单体,二乙烯基苯为交联剂,采用固相接枝聚合的方法制备接枝共聚物。讨论了反应温度、反应时间、阻聚剂、单体浓度和交联剂等对接枝率的影响。结果表明,接枝反应的最佳条件为:温度50℃,时间3 h,单体浓度10%,交联剂5%,阻聚剂(FeSO4.7H2O)0.08%,最佳条件下的接枝率为7.5%。

纳米ZnO-硬脂酸改性无纺布吸油性能研究

采用以纳米氧化锌与硬脂酸改性的无纺布为吸附剂,对植物油、汽油、柴油、煤油进行吸附性能研究。考察了硬脂酸用量、吸附时间、吸附温度对吸附性能的影响。结果表明:改性无纺布具有较好的吸油性能与疏水性能,在25℃,吸附30 min时,植物油、汽油、柴油、煤油的吸附倍率分别为21.4 g/g,16.30 g/g,12.80 g/g,9.8 g/g,吸油材料疏水性能良好,吸水倍率仅为3.4 g/g;吸油材料性能稳定,对植物油、汽油、柴油、煤油三次回用率分别为61.8%、64.8%、68.5%和63.7%,对植物油、汽油和柴油保油率较高,60 min后保油率分别为74.8%、72.5%和68.7%;纳米氧化锌与硬脂酸改性的无纺布吸附速率快,吸附倍率高,可回收利用,是理想的吸油材料。

二次回收PP无纺布条单螺杆挤出技术研究

阐述了单螺杆挤出机中PP无纺布条二次塑化过程中的进料连续性及塑化过程,研究存在的问题与解决方法,指出螺杆进料段、压缩段、计量段参数设计及螺筒外部段冷却是实现无纺布条不间断进料及塑化稳定挤出的关键要素。通过增加进料段摩擦力、调整压缩段压缩比和长度占比、调整计量段缝隙和屏障以及外部段控制温度解决关键问题。

PP熔喷非织造布原料性能及关键工艺研究

为研究高效低阻熔喷布的关键生产工艺,选取四种不同的熔喷专用聚丙烯原料,采用毛细管流变仪对聚丙烯原料的流变性能进行分析,并进一步在熔喷生产过程中考察不同模头孔径和温度、不同热风风温和风量以及不同接收距离(DCD)对熔喷布颗粒物过滤效率的影响。结果表明,四种聚丙烯熔体的非牛顿指数均小于1,熔体表现出切力变稀现象;同一剪切速率下,四种聚丙烯熔体的黏流活化能各不相同,生产过程中需根据原料特性严格控制温度;四种聚丙烯熔体的结构黏度指数均小于0.005,结构化程度均较小,可纺性好;同时,减小模头孔径,提高模头温度及在熔喷布克重相同的条件下,增加热风风温和风量及DCD距离,有利于降低熔喷纤维的平均直径,提高过滤效率。确定了熔喷非织造布的关键生产工艺:模头孔径0.28mm,热风风温275℃,热风风量32%,DCD 180 mm,开发出25 g/m 2熔喷布,在32 L/min流量下,盐性颗粒物过滤效率98.8%,过滤阻力17.9 Pa。

SiO_2气凝胶-无纺布或毡纳米复合材料的吸苯性能

具有纳米多孔网络结构的S iO2气凝胶与透气性优良的无纺布或毡进行复合,可得到具有高吸附性能的纳米复合材料,其饱和吸苯率达到并超过了传统的吸附材料。纳米复合材料的饱和吸苯率与单位面积所复合的S iO2气凝胶量和其本身的饱和吸苯率成正比关系,复合工艺对气凝胶孔结构的影响很小,符合一定的理论推导公式。