涤纶非织造吸声材料的吸声性能研究

研究涤纶非织造吸声材料的吸声性能。利用具有细度梯度的涤纶纤维制备了12种非织造吸声材料,测试分析了不同加固方式、纤维细度、针刺密度和材料厚度对涤纶纤维非织造吸声材料吸声性能的影响。结果表明:在所制备的涤纶非织造吸声材料中,采用针刺加固工艺、较细的纤维细度、较小的针刺密度以及较大的材料厚度,可以获得更好的吸声效果。认为:涤纶纤维可以作为非织造吸声材料应用,其吸声性能较好。     

香蒲绒非织造材料的制备及其吸声性能研究

为了研究香蒲绒非织造材料的吸声性能,以香蒲绒纤维为原料,采用非织造加工工艺,制备了9种香蒲绒非织造吸声材料。对香蒲绒非织造吸声材料在中频500Hz~1 600Hz和高频2 000Hz~6 300Hz范围内的吸声性能进行测试。结果显示:纤维的组成、针刺密度、材料厚度以及加固方法等因素对材料吸声性能有着不同的影响。认为:采用较小针刺密度制备的纯香蒲绒吸声材料具有更好的吸声效果,材料的厚度对吸声性能的影响比较明显,针刺加固比热熔加固更有利于材料吸声性能的提高。     

针刺吸声隔音纤维毡材料的应用及研究进展

文章概述了针刺纤维毡的结构性能和特点,对针刺纤维毡的吸声隔音原理及吸声性能的评价做了简要说明,分析了针刺纤维毡在材料选择方面的研究进展,认为针刺纤维毡在吸声材料中的应用前景广阔。     

纺织材料吸声性能测试与评价

吸声材料是降低噪声辐射的主要措施,合理选择吸声材料对吸声降噪具有非常重要的意义。衡量材料吸声性能的主要参数是吸声系数,因此实现其准确、快速的测量对声学材料研制、结构设计和优化有指导作用。对比分析了吸声性能测试的两种方法,介绍了阻抗管的吸声性能测试的各个测试指标,并在已有的吸声性能评价的方法的基础上,提出了一种新的评价方法。     

湖羊毛非织造阻燃吸声材料的制备及其性能

针对国内湖羊养殖规模不断壮大，但湖羊毛未能高效利用的问题，结合湖羊毛本身的性能及结构特点，采用针刺加工的方式开发一种汽车内饰吸声材料，以提高湖羊毛附加价值，保护天然资源不被浪费。通过针刺成形、缩绒整理、阻燃整理等加工过程制得吸声性能优良并具备阻燃功能的吸声材料。探究了材料的结构参数、缩绒工艺对湖羊毛非织造材料吸声性能的影响。结果表明：当湖羊毛非织造材料厚度大于3.5 mm,面密度大于350 g/m²时，在高频段(500～6 000 Hz)范围，其吸声系数大于50%,属于高效吸声材料。经阻燃整理后，湖羊毛针刺吸声材料的水平方向燃烧性能超过对汽车内饰材料阻燃标准要求(燃烧速度不大于100 mm/min),垂直方向燃烧性能达到阻燃标准要求。     

纳米纤维吸声降噪研究进展

为拓宽纳米纤维在声学领域的应用,促进高性能纳米纤维吸声材料的发展,对目前国内外纳米纤维的吸声降噪研究进展进行综述。首先分析了纳米纤维的吸声原理及吸声优势,认为纳米纤维的高比表面积与高孔隙率促进了其对中低频段声波的吸收;其次对影响纳米纤维吸声性能的因素进行了归纳与总结;然后重点阐述了纳米纤维对天然纤维、合成纤维与泡沫等材料吸声性能的影响,认为在常规吸声材料表面复合纳米纤维后可显著提升自身中低频段的吸声性能;最后针对纳米纤维吸声研究中亟待解决的问题以及如何制备绿色高性能的纳米纤维吸声材料进行了展望。     

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...     

麻纤维汽车内饰材料的吸声性能与针刺工艺的关系

本论文将黄麻纤维、苎麻纤维、大麻纤维分别针刺成毯,采用驻波管法测试其吸声系数,得出黄麻是很好的吸声材料。综合考虑原料来源及成本等因素,选取黄麻纤维为研究对象,利用单因素试验,分别探索针刺深度与针刺频率对黄麻针刺毯吸声性能的影响;以针刺深度、针刺频率、步进量为影响因素,设计3因素3水平正交试验,分别得出在200~500Hz的低频噪音范围内和630～2000Hz中频噪音范围内,使黄麻纤维针刺汽车内饰毯吸声系数最大时的最优工艺参数。     

非织造多孔吸声材料的发展与研究现状

介绍非织造多孔吸声材料的特点及影响因素.阐述了多孔吸声材料的吸声机理和评价指标,介绍了非织造多孔吸声材料的特点和种类划分.结合前人的研究,分析了影响非织造多孔材料吸声性能的因素,并介绍了当前非织造多孔吸声材料的研究现状和发展趋势.     

纤维基柔性吸声降噪材料的研究现状与发展趋势

文章概述了吸声降噪材料的吸声机理及柔性纺织类吸声材料的优势,纺织材料具有结构疏松、材料轻薄、加工性能好等特点,适用于吸声降噪产品的制备;从纺织材料的结构出发,从纤维种类、组织结构、吸声性能和应用特点等方面,分别介绍了机织物结构、针织物结构和非织造结构的吸声材料的研究进展及未来发展趋势。     

多层复合吸声结构的制备与性能研究

将穿孔板与氯化聚乙烯/七孔涤纶纤维复合材料进行复合制备了一系列的无后部空腔层的多层复合吸声结构。采用SW230驻波管运用传递函数法测试了复合吸声结构的吸声性能,分析了不同组合层数、组合方式、复合材料厚度以及穿孔板的孔隙率对吸声性能的影响。研究结果表明：在双层复合结构中,当穿孔板为测试面时,其吸声性能呈现多孔材料的特性;而测试面为复合材料时,吸声结构具有膜空腔共振的特性;当穿孔板层数超过二层时,复合吸声结构能将多孔材料吸声机理和共振吸声机理进行有机结合从而拓宽了其的吸声频域。是一种具有工程应用潜力的吸声结构。     

二次加固对复合针刺吸音材料结构和性能影响的研究

介绍了在普通涤纶中加入30％的热熔纤维,分别对其进行了两道针刺加固、模压定型和热风穿透粘合三种二次定型处理,并结合原针刺毡,分析比较了二次加固后材料的内部结构形态变化及其对材料吸音和机械性能的影响。结果发现复合针刺吸音材料经热处理二次加固,可以有效地提高材料强力和尺寸稳定性。     

中小型报告厅室内音质设计

本文对一个报告厅的体型设计、室内装饰材料和构造的选择和布置以及装饰风格进行了分析,以期使音质设计与装饰风格达到较好的统一。     

Effects of total surface area and fabric density on the acoustical behavior of traditional thermal‐bonded highloft nonwoven fabrics

Nonwoven fabrics are ideal materials for use in acoustical insulation products because they have a high total surface area, which is directly related to the denier and cross‐sectional shape of the fiber. The smaller the denier, the more fibers for the same material density, the higher the total fiber surface area is. This results in a greater opportunity for interaction between the sound wave and the fibers in the structure. Another important parameter is the density of the nonwoven material, which affects the geometry and the volume of the voids in the structure. The acoustical properties of fabric materials are measured using one of two methods: the impedance tube method and the reverberation room test method. The impedance tube method uses very small test samples (5–15 cm), whereas the reverberation room test method requires large test samples and is expensive to set up. For making comparative analysis of the test samples and overcoming the disadvantages of the current test methods, a direct comparative acoustical properties measurement device has been developed and fabricated in the School of Materials Science and Engineering at Clemson University in an attempt to overcome some of the disadvantages of the other method.     

Design of elderly cashmere-like wool clothing in outer wear performance北大核心

The purpose of this study is to design the cashmere-like wool clothing with the material properties. We would design cashmere wool clothing suitable for middle-age and old-age people. There are a lot of problems in middle aged clothing such as the style, incomplete specifications. we have to slove it by designing the middle aged clothes. This article compared the performance of three materials including acrylic, down jacket and cashmere-like wool. The design of the acrylic winter clothing should be applied to the design of the cashmere-like wool clothing. At the same time, we explored the middle aged clothing market and analysed the middle aged consumption custom. We got that natural fiber materials are popular by middle-aged people. This thesis will focus on the fleece winter clothes wear style. Ultimately, there will be more and more clothes styles of cashmere-like wool winter clothes popular with middle aged people.     

Acoustical performance of loose cork granulates

This paper reports on an investigation of the acoustical performance of loose cork granulates. This investigation is based on the physical parameters of loose granular cork obtained through an empirical model of the acoustic properties of loose granular media shown by Voronina and Horoshenkov and the experimental performance of these granulates. The performance is assessed according to ISO 10534-2 (1998). The data obtained show clearly that this porous absorber exhibits high sound absorption performance varying with particle size. The relationship between the experimental and the model results demonstrates the existence of significant differences between particle sizes >3.5 mm. Finally, the performance of this material is compared to other granular materials.     

Sound absorption characteristics of needle-punched sustainable Typha /polypropylene non-woven

Natural fibers are the acoustical sustainable materials used in blends with polypropylene as carded needle-punched non-woven for the automobile industry. Among the variety of natural fibers, studying the noise-absorptive properties of a novelty introduced fiber called Leafiran extracted from the Typha Australis plant has been aimed in this paper. Typha natural fibers were blended with polypropylene fibers in order to investigate the effect of this newly known natural fiber on the acoustic performance of producing non-woven composite structures. For this aim, five different blend ratios of Typha/polypropylene including 0:100, 30:70, 50:50, 70:30, and 100:0 were prepared. The non-woven porosity, areal density, and sound absorption properties were studied. Impedance Tube Method, which provides the normal incidence sound absorption coefficient (SAC) of materials, was used for determining the acoustic properties of produced non-woven samples. The results of SACs of Typha non-woven revealed that the Typha fibers have good acoustic performance with normal incidence absorption coefficient greater than 0.6 from 500 to 4 kHz. Finally, according to the obtained results from this research, it is claimed that Typha natural fibers could be an acceptable choice for sound reduction applications.     

新型汽车用热塑型复合材料

介绍了将农作物中的韧皮纤维，如洋麻、黄麻、大麻和亚麻等结合在一起制成具有可生物降解性的针刺热塑型非织造布的生产加工方法及其物理、机械和声学方面的性能。通过试验检测结果表明其制品由于具有质量轻、吸音性、拉伸性、压缩性等特点，可用于制造汽车内部构件。     

棉用不处理胶辊的主要技术性能分析

对表面不处理胶辊的主要技术性能，如抗绕性，回弹性，耐磨性，自身防护性进行了分析；并对胶料高分散度形态和表面粗糙度进行了分析和探讨。     

金属有机框架材料在食品包装中的应用

随着食品工业的发展,食品安全问题引起人们的广泛关注。金属有机框架（metal-organic frameworks,MOFs）是一类具有独特物理和化学性质的功能材料,其具有多孔结构以及显著的抗菌性能,因此在食品保鲜方面显示出良好的应用前景。在食品包装领域,MOFs可以延长食品的保质期并延缓贮藏期食品品质的劣变,提高食品包装材料的性能。本文综述MOFs作为抗菌剂、氧清除剂和乙烯清除剂在食品包装中的应用,介绍MOFs在食品包装领域的应用前景及面临的问题,旨在为MOFs在食品包装中的应用提供参考。