羊毛及其混合纤维非织造材料的吸声性能

为优化羊毛非织造材料的吸声性能,以羊毛、毛/涤、毛/麻3种纤维制备非织造材料。通过阻抗管对3种非织造材料的吸声性能进行测试,分析了声波频率在250-6 300 Hz范围内,材料的纤维种类、厚度和空腔深度对其吸声性能的影响。结果表明,3种样品的平均吸声系数均大于0.2,纯毛非织造材料的吸声性能略好于毛/涤材料与毛/麻非织造材料;通过增加材料厚度或设置空腔的方式均可提高材料全频段（尤其中低频段）的吸声性能,其中厚度对材料吸声系数的影响程度更大;从环保、材料价格、便于施工等方面考虑,以厚度为6 mm的毛/麻非织造材料作为吸声材料,并设置6 mm的空腔, 即可达到较为优异的低频吸声性能。     

薄型木棉非织造材料的性能研究

利用先针刺后热轧的非织造技术将木棉与ES纤维的混合纤维加工成具有一定稳定结构的薄型木棉非织造材料,并对其性能进行了研究。结果显示:当木棉的体积分数为70%时,木棉非织造材料的横向强力达到最大值;热水浸泡对木棉非织造材料的尺寸稳定性影响不大;木棉非织造材料在经受400次摩擦后,其质量损失量随着木棉配比的增大而逐渐增加;随着木棉配比的增大,木棉非织造材料的均匀性变差。     

双层复合非织造材料基吸声体吸声性能研究

以熔喷丙纶非织造材料和玻璃纤维水刺非织造材料为受声面和背衬层,通过热粘合方式制成双层复合非织造材料基吸声体。通过分析吸声体受声面和背衬层非织造材料的厚度、面密度、孔径、孔隙率等结构参数与复合吸声体的吸声系数之间的关系,探讨各层非织造材料结构参数对复合吸声体吸声性能的影响。实验结果表明,随着熔喷丙纶非织造材料和玻璃纤维水刺非织造材料厚度和面密度的增加,吸声体中高频段吸声系数显著提高;受声面和背衬层的孔径尺寸和孔隙率的变化对双层复合非织造材料基吸声体的吸声性能影响较为显著。     

聚酯纤维针刺非织造材料的吸声性能研究

主要研究了聚酯纤维针刺非织造材料在200~2 000 Hz声波频率范围内的吸声性能。从材料的厚度、针刺密度、表面粗糙度和组成纤维四方面来研究其吸声性能的影响因素。由实验得出,非织造材料的吸声性能主要取决于材料的厚度和表面特征,组成纤维也有一定的影响作用。     

结构参数对非织造材料吸声系数的影响

分别以涤纶针刺法非织造材料和丙纶熔喷非织造材料为基,通过热粘合方式制成不同参数的同质非织造材料吸声体。通过分析同质非织造材料吸声体的厚度、面密度、孔径、孔隙率等结构参数与其平均吸声系数之间的关系,探讨非织造材料结构参数对其吸声性能的影响。实验结果表明,对于同种材料而言,涤纶针刺非织造材料与丙纶熔喷非织造材料的结构参数对其平均吸声系数具有较大影响,材料的平均吸声系数随厚度和面密度的增加而增加。     

废旧羊毛非织造布的制备及其吸声性能

为研究废旧羊毛纤维非织造材料的吸声性能,利用非织造材料的生产工艺,以废旧羊毛纤维为主要原料,制备一种新型羊毛非织造材料。通过使用传递函数法和驻波管法,对羊毛非织造材料的吸声性能进行了测试,分析了声波频率为250-6300 Hz范围内,材料的厚度、密度和空腔深度对其吸声性能的影响。结果表明,羊毛非织造材料吸声性能优异,对高频的吸声性能优于低频;在中低声波频率,随材料厚度、密度和空腔深度的增加,其吸声性能越好。材料厚度和空腔深度是影响羊毛非织造材料吸声性能的主要因素;通过增加空腔深度提升材料的吸声性能,是较为经济合理的办法。     

基于BP神经网络的非织造材料基复合吸声体吸声系数预测

以涤纶针刺非织造材料和聚丙烯熔喷非织造材料为研究对象,通过实验获得其物理结构参数,并将复合前后非织造材料厚度、面密度、孔隙率和孔径作为BP神经网络的输入项,用于预测吸声体的平均吸声系数,同时通过调节输入神经元个数、传递函数和隐含层个数构建了最佳的BP神经网络预测模型。对非织造材料基复合吸声体的吸声性能进行预测,并与测试结果进行了对比。结果表明,运用BP神经网络可以建立较理想的适用于复合吸声体平均吸声系数预测的模型。     

针刺中空短纤非织造布层合涤纶增强橡胶基材料的吸声性能

测试分析了针刺中空短纤非织造布与四孔中空涤纶短纤增强氢化羧基丁腈橡胶基材料(HF材料)层合的双层和三层材料的吸声性能.结果表明:双层材料以非织造布为入射面时,呈现多孔吸声材料特性,整体吸声性能相比单一材料有所提升;以HF材料为入射面时,双层材料在中低频域的吸声性能显著改善,但中高频域的吸声性能下降.三层材料整体吸声性能...     

吸声隔音用纤维与非织造布复合材料

简介几类纺织纤维(植物纤维、无机纤维、合成纤维、金属纤维)及其非织造布复合材料在降噪领域的应用，说明了开发吸声隔音用纺织纤维与非织造布复合材料的现实意义。     

汽车用吸声非织造材料的应用现状及发展趋势

阐述汽车车厢内噪声的来源、危害及控制方法,详述非织造材料的吸声原理及其在汽车控声领域的具体应用,以及国内外吸声非织造材料的发展历程,介绍目前国外汽车用吸声非织造材料的开发情况,并对国内汽车用吸声非织造材料发展趋势进行预测。     

Characterization of needle-punched nonwoven fabrics for industrial air filter application

Needle-punched nonwoven fabrics with three different areal weights have been developed using micro-denier (0.8 Denier) and fine-denier (3 and 6 Denier) staple polyester fibers, separately. Process parameters such as punching density and depth of penetration have been changed according to the fabric areal weight. Effect of fiber fineness and areal weight on air permeability, tensile strength, bursting strength and compressibility of the fabric has been analyzed. It has been observed that air permeability decreases with the increase in areal weight of the nonwoven. The micro-denier fiber nonwoven gives 40% lower air permeability as compared with fine-denier fabrics. 6 Denier nonwoven provides 44% higher tensile strength as compared to 0.8 Denier nonwoven fabric and 23% higher tensile strength than 3 Denier fabrics. Compressibility and compression recovery of 6 Denier fabrics are also better as compared with other fabrics. However, micro-denier fabric shows 24% improvement in bursting strength and very good air dust filtration efficiency.     

纬编间隔织物及其吸声性能的研究

纬编间隔织物是采用纬编针织技术,用纱线或织物在垂直方向连接生产的两块独立织物,它具有特殊的结构和独特的吸声功能。介绍纺织材料的吸声机理,研究纬编间隔织物的编织生产工艺,分析纬编间隔织物的吸声性能及应用,认为纬编间隔织物在开发有吸声需求的产业用纺织品领域具有广阔的发展前景。     

Development of acoustic nonwoven materials from kapok and milkweed fibres

Acoustic properties of textile materials have been studied for several decades. But, mostly used materials were synthetic, and hence, they were not eco-friendly in nature. Therefore, an attempt was put forward to try the sound absorption property of natural fibres and their blends by needle-punched nonwoven techniques. Nonwoven fabrics of ideal materials are used as acoustical insulation products because they have high total surface area. The effect of blend proportion of kapok and milkweed fibres with cotton, fabric GSM, bulk density and distance of fabric from sound source on sound reduction of nonwoven fabrics was investigated. The sound reduction increases with increase in blend proportion of kapok and milkweed fibres. A nonwoven fabric of cotton/milkweed 40/60 shows the highest sound reduction potential. As the distance between the fabric and sound sources increases, the sound reduction also increases linearly due to reduction of sound intensity which reduces the transmission of sound through the fabric. There is a positive correlation between fabric GSM and sound reduction and negative correlation between bulk density and sound reduction. Further, the thermal conductivity of nonwoven samples decreases with increase in kapok and milkweed blend proportion due to increase in thickness of samples. Hence, the kapok- and milkweed-blended nonwoven samples provide sound as well as thermal insulation characteristics.     

The influence of production parameters on sound absorption of activated carbon fiber felts

Intended to study the influence of different production parameters on sound absorption of activated carbon fiber felts, viscose-based activated carbon fiber felts acquired from different production parameters were prepared and taken to test the sound absorption coefficients in normal incidence by means of transfer function method, within an acoustic range of 250–6300 Hz in the impedance tube. Analysis was made to find the influence of carbonization temperature, carbonization rate, activation temperature, and activation time on sound absorption properties. Sound absorption coefficients at medium–low frequencies strikingly climbed with the increasing frequency, while fluctuating at high frequencies. Other production parameters remaining constant, sound absorption coefficients increased at medium–low frequencies with the rising carbonization temperature and the extended activation time, while subsequently decreased with the rising carbonization rate and carbonization temperature. At the same time, sound absorption coefficients decreased at high frequencies with the rising carbonization temperature and carbonization rate, while increased but later decreased with the rising activation temperature, and increased again with the added time in activation.     

Recycling of cotton and polyester fibers to produce nonwoven fabric for functional sound absorption material

Recycled fibers are commonly used in dissimilar applications and one of the most important applications is sound absorption. Recycled fiber nonwovens currently are in greater demands in industries because of their advantages such as low cost, biodegradability, acceptable mechanical and physical properties, and so on. Sound absorption materials, renewable, and eco-friendly nonwovens have been developed using recycled cotton and polyester fibers. This research provides a contribution to the body of knowledge on the sound absorption properties of nonwovens using recycled fibers which contain cotton and polyester by means of spun-laid technique and provides a better understanding of the effects of a number of manufacturing processes on nonwovens noise control performance and also contributes to the wider adoption of nonwovens as sound absorbers. The sound absorption coefficients were measured according to ASTM E 1050 by an impedance tube method. The results revealed that the average of the sound absorption coefficients increased with the thickness of the nonwovens, but decreased with the nonwoven fabric density.     

活性炭纤维材料吸声性能预测模型

为了建立活性炭纤维材料吸声性能预测模型,利用阻抗管对不同规格的粘胶基活性炭纤维材料在250-1600Hz中低频率声波范围内的吸声性能进行测试,根据Delany和Bazley提出的特性阻抗率和传播常数理论模型,采用最小二乘法建立了活性炭纤维材料声学特征参数特性阻抗率和传播常数预测模型。在此基础上,建立了活性炭纤维材料吸声系数模型,并对该模型计算结果和试验结果进行了比较,结果表明两者结果基本相一致,验证了建立的活性炭纤维材料吸声性能预测模型具有一定的可信度,为开发和设计活性炭纤维吸声材料提供理论依据。     

Analysis of the effect of fiber cross section and different bonding methods on sound absorption performance of PET fiber based nonwovens using Taguchi method

Abstract

In this study, sound absorption coefficients (SACs) of needle-punched and thermal-bonded nonwovens produced from polyester (PET) fibers with various cross sections, i.e., hollow, round and hexaflower, blended with a low melt PET, was reported. The acoustic performance of a hexaflower PET fiber was studied for the first time. Fibers were carded and then one set of samples was bonded by needle punching while the other set was air-through thermal bonded. A third set of samples was needled at various punch densities. Design of experiments was planned according to Taguchi method. Relationship between production parameters and SAC was analyzed using Minitab software. The most important independent variables affecting the sound absorption were areal density and web bonding method. The sample produced according to optimum production levels reached to a SAC value of 0.57 at 2000?Hz which could be a suitable choice for acoustic applications in the automotive industry.     

废弃纤维吸声复合材料的制备及其吸声性能

针对废弃纺织纤维利用率不高的问题,采用共混-热压工艺,以废弃纤维为增强材料,以热塑性聚氨酯为基体材料,制备废弃纤维/聚氨酯复合材料。将废弃纤维/聚氨酯复合材料加工成穿孔板,并与废弃涤纶织物贴合,构成吸声复合材料。重点研究吸声复合材料中穿孔直径、穿孔板厚度、穿孔率及废弃涤纶织物层数四种结构参数对材料吸声性能的影响。结果表明,穿孔直径主要影响吸声材料的吸声系数峰值;穿孔板厚度、穿孔率和废弃涤纶织物的层数主要影响吸声材料的吸声频带范围。     

形状记忆聚氨酯在非织造织物中的应用

应用涂层工艺,将不同浓度的形状记忆聚氨酯涂覆到非织造织物上,制得具有不同聚氨酯含量的形状记忆聚氨酯非织造织物材料,并对处理前后非织造织物的表面结构、形状回复性、折皱回复性、透气透湿性、强伸力等性能进行了测试。实验结果表明:经形状记忆聚氨酯处理后的非织造织物具有很好的形状记忆功能,提高了非织造织物的抗皱性能;当聚氨酯含量较少时,对形状记忆聚氨酯非织造织物的透湿性没有显著影响,但透气性有明显下降。