Advanced Materials Research Vols. 332-334

Abstract: The relationship between structures and properties of Kevlar string was studied scarcely before, although the string was used in aerospace, spaceflight, ocean and the like. Kevlar braiding strings were designed and braided with different braiding angle, different core yarn content and different twist, and stretching properties were measured and analysed in the paper. The result shows that the bigger braiding angle is and the more core yarn content is, the higher break load is and the lower break elongation is. Besides, rupture analysis proves that braiding Kevlar bundles take hold of core Kevlar bundles tightly, both form an inseparable integrity almost during stretching. As a result, a special phenomena occurs, core Kevlar bundles are broken into several segments.

Abstract: The influence of temperature and time of dry-heat and wet-heat processing on the tensile property of the PLA fibers was investigated. The results indicate that as the temperature and time increase, the tensile strength of the fibers gradually decreases. When the temperature is above 100 °C or time over 20 minutes, the dry-heat treatment results in significant decrease on tensile property of the fibers. In the wet-heat treatment, the strength of PLA fibers is influenced by the treatment time, temperature and pH value. The acid-resistant property of PLA fibers is better than the resistance to alkali. Under weak acid condition, the performance of PLA fiber is relatively steady. But the fibers under alkali condition over 100°C are hydrolyzed into pieces and the force losses nearly completely. Moreover, the oxidant and reducing agent also impart the tensile property of PLA fibers. The concentration of H₂O₂ no more than 5g/L is appropriate, whereas the lower concentration of Na₂S₂O₄ is proper.

Abstract: Bamboo fiber, including natural bamboo fiber and recycled bamboo fiber, is a novel textile material of great economic value. The bamboo pulp fiber has been well received, whereas the development of the natural bamboo fiber is limited. The morphological structures of longitudinal and transverse sections were observed. The mechanical performance of bamboo pulp fiber was examined and the advantages of the fabric made of bamboo pulp fiber were discussed.

Abstract: In order to study on the anti-electromagnetic radiation performance of fabrics with silver-plated fibers, five sets of samples with polyester DTY and silver-plated nylon filament were manufactured for the experiment. The anti-electromagnetic radiation property of fabrics was tested with Flange coaxial method. The influence of different silver-plated fiber contents on the anti-electromagnetic radiation performance of fabrics was analyzed in this paper. The experimental results show that when silver-plated fibers are distributed by a network, anti-electromagnetic radiation performance of fabrics is better than that the silver-plated fibers are distributed only along the warp in fabrics. Meanwhile, the anti-electromagnetic radiation performance of fabrics improves as the increasing of the silver-plated fibers content. The anti-electromagnetic radiation performance of fabrics increases slowly when silver-plated fibers content is from 40% to 80%. The shielding effectiveness of fabrics for 10MHz~1000MHz electromagnetic waves increases not obviously when silver-plated fibers content is more than 80%, but that for 3000MHz is still rising. The anti-electromagnetic radiation performance of fabrics is the best when silver-plated fibers content reaches to 100%.

Abstract: In order to study the wearability of multi-component blended fabrics, there are 9 kinds of fabrics which belong to A, B and C three series were woven. They were blended with different proportions e.g. PTT, PLA, Cooldry, triangular shaped polyester yarn, cotton, hemp, viscose, conductive filament, and so on. Anti-pilling property, crease recovery, drapability, moisture transmission and air permeability of the fabrics were tested and analyzed. From the test results, following conclusions can be gotten. 1) The anti-pilling property is good for fabrics with tighter weave construction; 2) The crease recovery is good for fabrics with smaller weft density; 3) The moisture permeability is good for fabrics with smaller tightness; 4) The crease resistance, drapability, moisture permeability and air permeability of the fabrics can be improved by looser weave construction and smaller binding point.

Abstract: Fuzzing and pilling of fabrics, which is one of the factors that affect fabric appearance and wear behaviour, has plagued the people for a long time. With the development of living standard, people have higher and higher requirements on the properties of apparel. Several methods can be used for testing the fuzzing and pilling performance of fabric, and different methods often have different results. Using circular locus method and pilling box method on the four kinds of fabrics at the same time, conduct experimental data processing, compare the advantage and disadvantage of two methods and obtain the principle of selection of them. There are many factors that cause fuzzing and pilling, among which the overall covering factor is a significant one. Through the testing for four different kinds of cotton-wool mixed fabrics, with different warp density and different weft density, establish the relationship between the number of pills and the overall covering factor, and obtain the critical covering factor according to the one factor nonlinear regression equation.

Abstract: Heat and moisture comfort of several knitting underwear fabrics were measured and grey clustering analysis was applied to evaluate the heat and moisture comfort of these fabrics. According to the experimental data and grey clustering analysis results, the fibers can be ranked in terms of heat and moisture comfort as modal, bamboo and cotton, respectively. The evaluated fabrics were ranked as modal, bamboo, cotton/bamboo and cotton, in terms of heat and moisture comfort.

Abstract: With the rapid development of economic in China, more and more people are involved in Bodybuilding activities. As it is known to all, bodybuilding is the process which can bring massive heat and moisture, so it is vital for bodybuilders to have the excellent thermal-wet comfort of sports underwear. It is studied on dynamic thermal-wet comfort of ten styles sports underwear from the aspect of structure factors and it realized that subjective evaluation and data Acquisition are done at the same time. According to the result of subjective evaluation, it finishes the objective analyses which rely on varied and practical values of temperature and humidity, it gets the best style of thermal-wet comfort by the method of K-means clustering.

Abstract: The MWNTs-OH/PET composite fibers were prepared by the masterbatch melt blending spinning drawing one-step process (FDY), and the structure and properties of different contents of MWNTs-OH of the PET FDY fiber were studied. The results showed that the interaction between MWNTs-OH and PET matrix was enhanced after the modification of terephthalic acid (TPA), resulting in the improved interface compatibility. Also, the crystallinity of the composite fibers was raised 7% after the addition of modified MWNTs-OH. The fracture strength of composite fibers had firstly increased and then decreased with increasing of the content of MWNTs-OH, the strength of the composite fiber was largely improved by 60.5% with 0.2% (wt) of TPA/MWNTs-OH.

Abstract: This paper stated the preparation of nano-TiO₂ via Sol-Gel method and modification of nano-TiO₂ by coupling agent—MPS. Then Ethanol/PSt and nano-TiO₂/PSt core-shell hybrid particles were prepared via miniemulsion polymerization by using the cationic surfactant Cetyl Trimethylammonium Bromide as emulsifier and Cyclohexane as co-stabilizer. These two hybrid nano-particles were added to the sizing agent—SX-5 respectively, to determine the sizing agents’ adhesive force to Terylene (T) and Terylene/Cotton (T/C) yarns respectively via roving method. The breaking strength and hairiness number of T/C yarns were determined by single yarns’ sizing method. The adhesive force of T and T/C yarns, breaking strength and hairiness number of T/C ones, showed that small size effect, high fluidity, and high surface energy caused by large specific surface area of hybrid nano-latices would make a great contribution to sizing properties.