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991.
992.
Abolfath Akbarzadeh Javad Mokhtari Shirin Kolkoohi Mohammad Amin Sarli 《应用聚合物科学杂志》2012,126(3):1097-1104
Insect repellency of fiber is a property which makes the fiber to be of interest in the field of military and health. The insect‐repellent substrate could be prepared using either functional finishing or applying an insect‐repellent dye. In this article, insect‐repellent nylon 6 is obtained using a novel insect‐repellent reactive dye containing N,N‐diethyl‐m‐toluamide. To do this, N,N‐diethyl‐m‐toluamide (DEET) was first nitrated at the p‐position relative to amide functionality. The nitrated product was reduced in the presence of C2H5OH, SnCl2, and HCl. The produced amine was then condensed with 2,4,6‐trichloro‐1,3,5‐triazine (cyanuric chloride) as a reactive group in below 5°C. The resultant adduct was finally reacted with an amino group present in 6‐amino‐1‐hydroxy naphthalene‐3‐sulfonic acid (J‐acid) to produce 7‐(4‐chloro‐6‐(4‐(diethylcarbamoyl)‐2‐methylphenylamino)‐1,3,5‐triazin‐2‐ylamino)‐4‐hydroxynaphthalene‐2‐sulfonic acid. To synthesis azo dye, sulfanilic acid was diazotized using HCl and NaNO2 and then coupled to the above prepared component to produce insect‐repellent reactive dye. An analog dye was prepared via the same route without insect‐repellent group making stage. The chemical structures of the novel dyes were characterized using FTIR and 1H‐NMR spectroscopy. The spectroscopic properties of the dyes were determined in terms of λmax and εmax in aqueous solution. The novel dyes were then reacted with nylon 6 and bonded to it covalently to provide permanent insect‐repellent substrate. The insect‐repellent efficacy of the reacted nylon 6 was studied using standard methods for Anophele mosquito repellent. The insect‐repellent dye reacted nylon 6 showed insect‐repellent activity. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
993.
纳米SiO2对火焰喷涂尼龙1010涂层干摩擦磨损性能的影响 总被引:1,自引:0,他引:1
为了探讨纳米SiO2(n-SiO2)对火焰喷涂尼龙(PA)1010涂层干摩擦磨损性能的影响,采用MRH-3型环-块摩擦磨损试验机对不同n-SiO2含量的尼龙1010涂层的干摩擦磨损性能进行了测试;并利用扫描电子显微镜(SEM)对复合涂层的磨损表面进行观察,以探讨n-S iO2对火焰喷涂尼龙1010涂层摩擦磨损性能的影响机制。结果表明:n-SiO2的加入能明显提高尼龙涂层的耐磨性,降低摩擦因数,疲劳磨损、粘附磨损及犁切现象明显减轻;当n-SiO2含量为1.5%(质量分数)时,复合涂层摩擦磨损性能最佳,试验条件下磨损量降低近4倍,摩擦因数降低23%,跑合期降低44%,复合涂层与GCr15钢环对磨时的磨损机制主要为疲劳磨损和轻微的粘附磨损。 相似文献
994.
《Journal of Adhesion Science and Technology》2013,27(6):639-654
The capillary wetting rates in nylon fibrous assemblies were evaluated from the change in electrical conductivity due to wetting. The wetting liquids used were aqueous potassium chloride solutions of various pHs, in both the absence and the presence of ionic surfactants. Sodium dodecyl sulfate and dodecyltrimethylammonium chloride were chosen as surfactants. The contact angles of the wetting liquids on the nylon fiber were measured by the Wilhelmy method and the isoelectric point of the fiber was determined from electrokinetic data. The minimum wetting rate and the maximum contact angle were observed near pH 4, which coincided with the isoelectric point of the nylon fiber. In the presence of surfactant ions, the minimum wetting rate was also obtained at the concentration where the surface charge of nylon was neutralized. These experimental findings indicate that the capillary wetting rates in nylon fibrous assemblies are influenced by the electrical phenomena at the nylon/ solution interfaces via the contact angle and the structure of the adsorbed surfactant layers. 相似文献
995.
增强尼龙中玻纤长度及其分布对性能的影响 总被引:2,自引:0,他引:2
以玻纤填充质量分数为30%玻纤增强尼龙6为例,分析和研究了玻璃纤维长度及其分布对增强尼龙6主要性能的影响。结果表明:玻璃纤维的平均长度越长,增强尼龙6的拉伸强度越大,但熔体流动速率下降;玻璃纤维的分布越均匀,缺口悬臂梁冲击强度越大;而弯曲模量与纤维最大长度成正比关系。 相似文献
996.
采用原位插层聚合法制备了尼龙6/蒙脱土剥离型纳米复合材料,讨论了超分散有机蒙脱土的用量对复合材料性能的影响,用动态力学分析(DMA)、X射线衍射(XRD)、扫描电镜(SEM)和透射电镜(TEM)等手段研究了纳米复合材料的结构和性能。结果表明,有机蒙脱土加入量为3%(质量分数,下同)时,复合材料综合性能最佳;有机蒙脱土的加入大大提高了尼龙6的综合性能,并提高了尼龙6的储能模量和玻璃化温度。有机蒙脱土在尼龙6基体中有良好的分散性和相容性,蒙脱土片层被完全剥离,在尼龙6基体中实现了纳米级分散。 相似文献
997.
998.
Nylon 6 nanofibers containing organic photosensitizers were investigated to demonstrate the antimicrobial properties in the application of the material to protective clothing and home appliances. Benzophenone (BP), 4, 4′‐bis(dimethylamino)benzophenone (MK) and thioxanthen‐9‐one (TX) were used as photosensitizers and the nylon 6 nanofibers were prepared using electrospinning. Field emission scanning electron microscopy morphology of the nanofibers showed that even and continuous nylon 6 nanofibers were well prepared through electrospinning and that the organic photosensitizers were evenly distributed in the nanofibers. There was no significant reduction of crystallinity in the nylon 6 nanofibers through the insertion of the organic photosensitizers. After UV (365 nm) irradiation of the photosensitizers, the intensity of peak photon excitation in the electron spin resonance spectra was increased. Antimicrobial properties of the prepared nanofibers were tested against Staphylococcus aureus and Escherichia coli according to JIS Z 2801. It was found that antimicrobial properties of nylon 6 nanofibers containing MK and TX were superior to those of nylon 6 nanofibers containing conventionally used BP. The antimicrobial effects of the nanofibers for S. aureus were superior to those for E. coli. The antimicrobial activity gradually increased as the UV irradiation time increased. Copyright © 2012 Society of Chemical Industry 相似文献
999.
湿度是影响高分子材料机械性能的重要因素之一。本文综述了湿度对尼龙、环氧树脂及高分子复合材料机械性能的影响,有助于了解材料在使用过程中可能出现的问题。结果表明湿度影响高分子材料主要通过渗透到吸收这个过程,湿度对不同高分子材料产生的影响与材料的结构与应用有关。 相似文献
1000.