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931.
Laser scanning confocal microscopy (LSCM) has been used to characterize the changes in film thickness and local surface morphology of polymer coatings during the UV degradation process. With the noninvasive feature of LSCM, one can obtain thickness information directly and nondestructively at various exposure times without destroying the specimens or deriving the thickness values from IR measurement by assuming uniform film ablation. Two acrylic polymer coatings were chosen for the study, and the physical and chemical changes of the two systems at various exposure times were measured and analyzed. Those measurable physical changes caused by UV exposure include film ablation, formation of pits and other surface defects, and increases in surface roughness. It was found in both coatings that changes in measured film thickness by LSCM were not correlated linearly to the predicted thickness loss using the changes in the CH band obtained by the Fourier Transform Infrared (FTIR) spectroscopy measurements in the later degradation stages. This result suggested it was not a uniform film ablation process during the UV degradation. At later stages, where surface deformation became severe, surface roughness and profile information using LSCM were also proven to be useful for analyzing the surface degradation process Presented at the 81st Annual Meeting of the Federation of Societies for Coatings Technology, November 13–14, 2004 in Philadelphia, PA.  相似文献   
932.
本文浅述了含氟高分子材料的特性及其在汽车,建材方面的应用状况,分析了含氟材料对汽车、建筑业的支持作用和发展方向。  相似文献   
933.
对纤维的需求不断增长,天然纤维缺口将愈来愈大,均为化纤发展带来了机遇。化纤工业竞争激烈,主要趋势为扩大规模提高效率。无人化、环保化也是一种趋势。同时也发展了一些与下游名牌产品联系在一起的小型专业厂.高技术、高性能纤维发展较快.在技术方面,认为纤维超细化、废弃物回收重新纺制纤维,注意环保,设备增容、高效化,高性能纤维开发等是主要趋势.  相似文献   
934.
赵友云  王玉秀 《聚酯工业》2002,15(3):19-20,25
用HEBERLEINP2 12网络喷嘴 ,在法国ICBTFTF12E3加弹机上生产不同网络度和牢度的网络丝。探讨了网络张力、压缩空气压力等工艺条件与网络度和牢度的关系 ;优化工艺参数 ,生产的网络丝满足了市场多样化的需求。  相似文献   
935.
软岩的崩解、泥化往往给工程带来困难和损失。崩解、泥化实际上是岩体失水-吸水-膨胀的过程,水在这个过程中起着关键性的作用。硅烷偶联剂一树脂涂料中由于硅烷偶联剂在岩体表面和树脂问的架桥作用,使得涂层具有吸附牢固、疏水性好的特点,起到了阻止岩体与外界水分交换、加固岩体的作用。硅烷偶联剂一树脂涂料在软岩工程方面有着广阔的应用前景。  相似文献   
936.
以凹凸棒粘土作为高水速凝固化充填材料的悬浮稳定剂,考察了不同制浆机械对凹凸棒粘土制浆率的影响。采用高剪切混合乳化机预制的1%凹凸棒粘土浆配制高水速凝固化充填材料甲、已料单浆可获得满意的悬浮稳定效果。其充填体结石抗压强度早期发展迅速,后期持续增长。采用此工艺,注浆料的材料成本仅增加2%。  相似文献   
937.
介绍了HYJ—01喷补料的实验室研制及工业应用。实践表明,该喷补料粘接强度好,抗热震性好。喷补衬使用时间已超过14个月,无明显破损现象。  相似文献   
938.
The effects of oxyen plasma treatment on the surface chemistry of Spectra 1000® high modulus polyethylene fibers and on the mechanical properties of fiber-reinforced composites of the fibers in a Bis-GMA based acrylic resin have been studied. X-ray photoelectron spectroscopy and diffuse reflectance FTIR spectroscopy have been used to show that the majority of oxygen on the fiber surface exists mostly in the form of ether and/or epoxy linkages, with carbonyl-, carboxylic- and ester-containing compounds accounting for less than 10 percent of the total. While the untreated and plasma-treated fibers have similar chemical compositions, the surfaces of the plasma-treated fibers are more polar and the oxygen is chemically bonded instead of being merely physisorbed. The interfacial shear strength between the fibers and the acrylic resin is increased by a factor of 2.3 by the plasma treatment indicating the presence of a weak boundary layer on the surface of the untreated fibers. The hydrolytic stability of the composite interfaces was investigated for fibers sized with several Bis-GMA-based adhesives. Maximum stability was attained by sizing with Bis-GMA containing a peroxide catalyst or an amine accelerator. The flexural properties of composites utilizing plasma-treated and untreated fibers were compared in three-point bending. The ultimate bending loads for composites using treated fibers were much higher than those for composites with untreated fibers, but only a fraction of that for glass or Kevlar®-reinforced materials.  相似文献   
939.
发展玻璃纤维产业纺织品   总被引:2,自引:0,他引:2  
本文层层深入地介绍产业用纺织品发展与应用、玻璃纤维纺织品发展与应用,以及它们的国内外概况并给出一些意见,以期待玻璃纤维产业纺织品有更好的发展.  相似文献   
940.
An isotactic polypropylene hollow microfiber was continuously produced by using a carbon dioxide (CO2) laser‐thinning method. To prepare the hollow microfiber continuously, the apparatus used for the thinning of the solid fiber was improved so that the laser can circularly irradiate to the hollow fiber. Original hollow fiber with an outside diameter (OD) of 450 μm and an internal diameter (ID) of 250 μm was spun by using a melt spinning machine with a specially designed spinneret to produce the hollow fiber. An as‐spun hollow fiber was laser‐heated under various conditions, and the OD and the ID decreased with increasing the winding speed. For example, when the hollow microfiber obtained by irradiating the CO2 laser to the original hollow fiber supplied at 0.30 m min?1 was wound up at 800 m min?1, the obtained hollow microfiber had an OD of 6.3 μm and an ID of 2.2 μm. The draw ratio calculated from the supplying and the winding speeds was 2667‐fold. The hollow microfibers obtained under various conditions had the hollowness in the range of 20–30%. The wide‐angle X‐ray diffraction patterns of the hollow microfibers showed the existence of the highly oriented crystallites. Further, the OD and ID decreased, and the hollowness increased by drawing hollow microfiber obtained with the laser‐thinning. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2600–2607, 2006  相似文献   
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