热定型工艺对底网针刺造纸毛毯性能的影响

为进一步优化底网针刺造纸毛毯生产过程中的热定型工艺,选择温度、时间和含湿率3个因素,采用正交试验的方法对底网造纸毛毯进行热定型试验,并对热定型前后的造纸毛毯进行压缩回弹性、透气性和滤水性等性能的测试。运用模糊数学方法对试验数据进行分析,确定热定型的最佳工艺。结果表明:经过热定型处理造纸毛毯的透气性能和滤水性能均会下降,而压缩回弹性能得到改善。本文试验用底网针刺造纸毛毯的热定型最佳工艺为:温度240℃,时间为正面60 s,反面30 s,含湿率30%。     

PP/玄武岩纤维针刺土工布制备及性能分析

为研究影响PP/玄武岩纤维针刺土工布性能的主要因素,以聚丙烯纤维、玄武岩纤维为原料,选取纤维比例、针刺密度、针刺深度和热轧温度设计四因素三水平正交试验,利用非织造技术制备了9种PP/玄武岩纤维针刺土工布样品。测试9种样品的单位面积质量、厚度、透气率、拉伸强力、撕破强力等。结果表明,影响产品主要性能的因素依次为纤维比例、针刺密度、热轧温度、针刺深度;优化的工艺参数为PP/玄武岩纤维比例为90/10,针刺深度为11 mm,针刺密度为300刺/cm~2,热轧温度为175℃;PP/玄武岩纤维针刺毡热轧后各项性能有较大变化,其拉伸强力、撕破强力都有较明显的提高,厚度和透气性能有明显的下降。     

涤纶单丝的张力热定型工艺研究

涤纶单丝广泛应用于经编间隔织物,作为承力单元单丝的力学性能很大程度上决定了织物的抗压缩性能。研究了单丝的热定型工艺对其力学性能和微观结构的影响,通过对涤纶单丝进行不同温度和时间的张力热定型处理,测试定型前后单丝的单向拉伸性能和结晶度,分析了热定型时间和温度与单丝初始模量和结晶度的关系。结果表明,随着热定型时间的增加,涤纶单丝的初始模量先增大后减小;热定型温度为180℃时,涤纶间隔单丝的初始模量大于200℃时的初始模量;张力热定型提高了涤纶单丝的结晶度。最佳热定型工艺是180℃,时间20 s。     

针刺工艺参数对非织造布性能的影响

针刺非织造布是非织造产品中发展较快的产品之一。本文探讨了两种主要的针刺工艺参数对非织造布各项性能的影响。经实验验证及理论分析 ,得出了针刺密度、针刺深度与非织造布物理性能、机械性能及过滤性能的关系     

超仿棉针织物热定型工艺探索

在超仿棉针织物的热定型过程中加入纤维保护剂可以提高织物的热定型温度,在获得稳定尺寸的同时,织物具有良好的折皱回复性、顶破强力和手感。试验结果表明:纤维保护剂质量浓度和热定型温度是影响超仿棉针织物热定型效果的显著因素;在DP9810纤维保护剂溶液质量浓度110 g/L、热定型时间30 s、热定型温度140℃的工艺下,超仿棉针织物的热定型效果较好。     

热定型温度对涤纶针织物性能的影响

为研究热定型温度对涤纶织物各种性能的影响,特别是抗凝血性能的影响,对经不同温度热定型的涤纶针织物进行了结构、活化部分凝血活酶时间APTT、血浆凝血酶原时间PT、血小板黏附性能、吸水性能、染色性能测试和评价。结果表明:随着热定型温度的升高,涤纶针织物的横向、纵向收缩率都在增加;热定型温度为150℃时涤纶织物的吸水性能、抗凝血性能、染色性能均最差;通过对APTT、PT的变化比较可以看出,对织物进行热处理大大抑制了织物的外源性凝血因子PT的激活。     

定长热定型对聚苯硫醚熔喷非织造布性能的影响

采用不同温度和时间,对实验室制备的聚苯硫醚(PPS)熔喷非织造布进行定长热定型处理,并对处理前后的PPS熔喷非织造布的尺寸稳定性、微观形貌和拉伸性能进行表征。结果表明:采用不同的热定型条件,均能获得尺寸稳定性良好的PPS熔喷非织造布;热定型后,PPS熔喷非织造布的微观形貌不发生明显变化,纤维玻璃化温度提高,拉伸强度增大,断裂伸长率下降。     

化纤造纸毯热定型理论和实践的探讨

造纸毛毯是非织造布针刺工艺的主要产品,造纸毛毯的热定型工艺决定了产品的性能.文章从纤维的热学原理上分析了造纸毛毯的热定型工艺及所使用的热定型设备,建议改热辐射式为热风对流式或金属接触传导式,以提高造纸毛毯的档次.     

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。     

超长涤纶短纤维针刺土工布性能研究

以长度为51、65和150 mm的涤纶短纤维为原料,采用非织造针刺技术加工制得土工布。研究了原料纤维长度、针刺密度和针刺深度对土工布力学性能、厚度、垂直渗透系数的影响。结果表明:增加土工布原料纤维长度可以明显提高土工布力学性能;合理地选择针刺深度和针刺密度,有助于提高土工布的力学性能及透水性能。     

Study on needle punched jute nonwoven as an artificial medium for germination of seed: Effect of bulk density

A uniform, porous, and bulky mechanically entangled fibrous sheet, i.e., needle-punched nonwoven, from eco-friendly and natural, low-grade jute fiber, has been designed and engineered to use as an artificial medium for germination of seed in place of soil. Needle-punched nonwoven fabrics of different bulk densities have been prepared from low-grade jute. Bulk densities of needle punched nonwoven fabric can be changed due to change of punch density, area density and depth of needle penetration. In this case, bulk densities of fabric have been achieved by varying the punch densities only, keeping the area density and depth of needle penetration same/ unaltered. As per experimentation, 500 g/m² area density needle punched nonwoven with 0.116 g/cm³ bulk density shows the best quality of germination. This bulk density has been achieved using 160 punches/cm² and 13 mm depth of penetration as per the system applied and fiber used. It may be a good alternative as a medium of cultivation. The design of the bed is also proposed in the article. It is observed that in this artificial system, cultivation can be made in hostile condition and plant growth is better than that in soil. Its moisture-holding capacity and temperature control of medium help in better agriculture. This is highly applicable in the regions where soil is either not available or not suitable for cultivation.     

Electrical resistance of jute needle-punched non-woven fabric – effect of punch density,needle penetration and area density

The electrical resistance of jute needle-punched non-woven fabric has been studied. Statistical model using central composite rotatable experimental design is developed for electrical resistance depending on the three important parameters of needled non-woven fabric, i.e. punch density, depth of needle penetration and mass per unit area. From this model and its contour diagrams, the effects of different parameters can be understood on electrical resistance of those fabrics. Prediction of electrical resistance can be made knowing the values of independent parameters. The correlation coefficients between observed and predicted values are found to be significant in all the cases. As depth of needle penetration increases for a particular punch density, electrical resistance increases and after reaching to maximum, it decreases having optimum at about 140 punches/cm² and 12?mm depth of needle penetration. With the increase of area density, resistance decreases. As punch density increases for a particular area density, resistance increases for high needle penetration.     

PDMDAAC的合成及其AKD施胶熟化性能

以二烯丙基二甲基氯化铵(DMDAAC)为原料,采用过硫酸铵/亚硫酸氢钠引发体系,水溶液合成聚二烯丙基二甲基氯化铵(PDMDAAC),并将合成产物作AKD的熟化剂以提高AKD的快速熟化性能。结果表明:40%单体浓度聚合的合适工艺为反应温度65℃,反应时间7h,引发剂0.3%。合成产物能提高AKD的熟化效率,纸页的下机施胶度可达到85%左右,适度控制PDMDAAC的电荷密度和分子量有助于改善AKD的施胶熟化性能。     

机织过滤布的设计与生产

阐述了机织过滤布的用途及原料品种、规格的选择和织物结构的设计,并从理论和实际两方面介绍了其产品生产工艺的确定,得出整经工序汽蒸筒纱和织造工序增加打纬力,严格控制温湿度是生产的关键.并介绍了目前国内生产状况.     

Ranking fibre and process parameters affecting thermal resistance of needle-punched blankets using neural network model

In this paper, an artificial neural network (ANN) model has been designed to predict the thermal resistance of needle‐punched blankets. Web‐laying (parallel‐ and cross‐laid), fibre fineness, fibre degree of hollowness, fabric weight, depth of needle penetration and needle punch density are considered as input parameters to predict the thermal resistance of needle‐punched nonwoven blankets. In order to reduce the dependency of the results on a specific partition of the data into training and testing sets, three‐way cross validation tests were performed, that is, total data were divided into training and testing sets in three different ways. The predicted thermal resistance correlated well with the experimental thermal resistance. The relative contribution of each parameter to the overall prediction of the thermal resistance was studied by carrying out a sensitivity analysis of the test data set. The results of sensitivity analysis show that web‐laying is the most important input parameter, followed by depth of needle penetration, fabric weight, degree of fibre hollowness, needle punch density and fibre fineness.     

针刺滤布生产中纤维、针布和刺针的选配

为了提高针刺非织造布产品品质,从针刺滤布用原料纤维、梳理用针布及刺针选配三个方面进行了详细阐述。指出:纤维是针刺非织造布基本原料,其物理性能指标直接影响最终产品的质量;在生产前首先应掌握原料纤维的物理性能指标、优缺点及影响最终产品的关键点,并针对纤维、设备及具体工况条件制定工艺;梳理工艺在非织造布生产中十分关键,它又是通过针布来实现的,所以应根据所加工的原料品种、纤维性能、各辊筒尺寸及工艺参数,纤网克重及纤网杂乱要求等具体参数选择合适的针布规格及配置参数;刺针型号及刺针品质直接决定产品质量,应根据原料纤维细度,针刺工艺、工序作用具体选择刺针,同时刺针使用厂应和制造厂密切配合、交流,不断修正、提高刺针质量以适应生产需要。     

浅析针刺联合机的设备配置

介绍了针刺联合机的设备配置情况和主要设备的性能参数以及配置联合机时应该注意的问题．阐述了针刺联合机配置的原理和设计方法，说明了只有合理的设备配置，才能生产出品质优良的针刺产品。     

Thermal inactivation of Listeria monocytogenes on ready-to-eat turkey breast meat products during postcook in-package pasteurization with hot water

The inactivation of Listeria monocytogenes during postcook in-package pasteurization was evaluated for fully cooked turkey breast meat products (4-kg packages). The products were surface-inoculated to contain 10(7) CFU of L. monocytogenes per cm2 of product surface. The inoculated products were vacuum-packaged in different thicknesses (0.08 to 0.33 mm) of packaging films and treated with hot water at 96 degrees C. After heat treatment, the products were immediately cooled in an ice water bath at 0 degrees C. The relationship between heating time and product surface temperature was determined for different thicknesses of packaging films. The effectiveness of heat treatment for inactivating the pathogen was affected by product surface roughness. About 50 min of heating time was needed to achieve a thermal kill of 7 log10 CFU/cm2 on products with surface roughness up to 15 mm in depth. The cooling time needed after a heat treatment increased with an increasing endpoint temperature of the heated product and the heat penetration depth reached in the product. The cooling time needed to cool the product from 71 degrees C to 4 degrees C was about 2.5-fold the heating time.     

花式嵌线的试制

花式嵌线是由1股涤纶长丝和1股短纤维纱并合加捻而成,与一般的嵌线生产有较大区别。文章介绍了花式嵌线的生产试制,工艺设计从混条机开始,经过四道针梳,再经过粗纱机的进一步牵伸,制成粗细适当及卷装合理的粗纱条;后纺再将粗纱条经过细纱、络筒、并线、倍捻、蒸纱等工序。试制结果:制成了条干均匀、表面光洁、捻回稳定、强力好、卷装大、适宜织造加工的筒子纱。文章重点对各工序的技术参数进行合理设计和调整、对生产中半制品质量上出现的问题进行探讨,提出了提高产品质量的具体措施。