共查询到19条相似文献,搜索用时 156 毫秒
1.
简要介绍了涂(镀)层自然气候曝露试验的目的和方法,描述了试样的类型和制备、试样的标识、试样的数量要求,试样数据记录手段.阐述了大气曝露试验场的气候特征及其大气环境数据记录要求,曝露试验架的制作方法,试验方法和结果评价措施. 相似文献
2.
本文叙述尼龙1010,ABS(通用型和耐寒型)聚碳酸酯(光气法和酯交换法)、通用聚苯乙苯(纯聚苯乙烯和加有抗氧剂的聚苯乙烯)、改性聚苯乙烯(接枝型和混炼型)在我国6个不同气候地区进行大气曝露试验后的力学性能变化情况,以缺口冲击强度表示9种工程塑料在不同气候地区的老化结果。 相似文献
3.
胡行俊 《合成材料老化与应用》1984,(1)
一九八三年六月一、铫子曝露试验场建场的历史背景和场地选择: 早在60年代,日本已开展金属材料大气曝露试验,但那时的曝露试验都是分散进行的,当时全日本大约有20多个属于各企业公司的小型曝露试验场。随着日本工业技术的发展,日本防锈技术协会极力主张建立标准的曝露试验方法和设置大气曝露试验场,该主张得到日本政府的支持,于昭和44年(1969年)接受了日本自行车振兴会的资助金成立了“关于大气曝露试验研究机构的调查辅助业务”,于1969年对美国和西欧7个国家有权威的12个曝露试验场进行了实地考察,发现欧洲的曝露试验场一般为国家管理机构,而美国多数为各 相似文献
4.
马文杰 《合成材料老化与应用》1989,(2):51-52
苏联是世界上曝露试验场最多的国家之一,曝露场遍布于全国各个气候区域。据不完全统计,约有曝露场、站五十个(注)。早在社会主义工业化时期,苏联就已设立第一批曝露场,对高分子材料进行大气老化试验。四十年代,苏联科学院物理化学研究所首先在全苏组织建立曝露试验网。六十年代初,中苏关系中断后,苏联在国内迅速陆续建立了一批新的曝露场, 相似文献
5.
用红外光谱法跟踪聚乙烯标准参考片气候暴露过程的分子结构变化,发现其羰基生成与链端乙烯基的增长线性相关,但斜率tg随曝露环境而变,称e为气象综合作用角。研究证实,这个描写曝露膜分子结构变化的参数能够用来表征聚合物环境的气候特性和评价人工气候装置对自然气候的模拟性,在统计分析广州30的地面气象上基础上,结合对市售气候的结构与性能之佗们仿造自然气候能力与局限,建议优先到阳光下试验,经济又可靠。 相似文献
6.
光-生物降解发泡PS快餐具性能评价方法研究 总被引:1,自引:0,他引:1
本文通过对国内几家单位所开发的光-生物降解发泡聚苯乙烯餐盒使用性能和降解性能的实验研究,初步提出对该类餐盒应从理化指标、毒性指标及样品经氙灯光源加速老化试验、自然气候曝露实验和野外降解实验后红外光谱分析、样品厚度变化及分子量变化情况的测试等几个方面进行评价,为该类产品的研制、开发及应用提供了依据。 相似文献
7.
黄衮威 《合成材料老化与应用》1985,(4)
通常在美国推行的所有户外气候试验方法和在佛罗里达试验场进行的试验,是把样品放在敞开式的试验架上,通过最短时间的试验,使样品光泽出现典型的变化。有关暴露样品清洗问题的实施控制和试验的暴露角度,都对试验结果有关键性的影响。 相似文献
8.
朱福海 《合成材料老化与应用》1978,(3)
“户外曝露”系指将试验样品放置在户外自然环境下,经受各种气候因素综合作用的一种试验方式。与此术语词义相当的称谓还有“大气曝露”、“室外曝露”、“自然曝露”、“天然曝露”以及“天候曝露”等。“户外曝露”一词相当于英语的“Outdoor expoaure”, 相似文献
9.
主要叙述了几种耐候聚丙烯人工气候加速老化试验和大气曝露试验结果,根据其中的冲击强度、拉伸强度、断裂伸长率的变化率及外观颜色进行分析比较。 相似文献
10.
魏本立 《合成材料老化与应用》1988,(4)
航空有机玻璃老化试验协作组组长单位代表会议于11月22日至24日在广州召开。出席会议的有化工部、空军、航空工业部所属的有关单位代表共11人。与会代表前往新建成的合成材料老化研究所曝露试验场现场考察了试验样品情况,认真地逐个检查了样品,仔细地观察研究了样品表面的老化状态,并作了详细的记录。会上对目前试验情 相似文献
11.
本文介绍了气候试验的种类、测试原理、工作流程及其在粉末涂料涂装研发中的应用,说明气候试验对粉末涂料与涂装产品老化性能的评价以及原材料的选择都有着重要的指导作用。 相似文献
12.
常温固化FEVE氟碳涂料耐候性研究 总被引:2,自引:0,他引:2
通过自然老化、人工加速老化、ESEM分析研究了不同类型FEVE氟碳涂料的耐候性。结果表明:FEVE氟碳涂料具有非常优异的耐候性;具有更大交替性的醚类单体和位阻型大单体合成的FEVE氟碳树脂具有更优异的耐候性。 相似文献
13.
The island blister test has recently been proposed as an adhesion test which allows the peel of thin, well-adhered films without exceeding the tensile strength of the film. The island blister test site is a modification of the standard blister test site, consisting of a suspended membrane of film with an “island” of substrate at the film center. The membrane support and island are secured to a rigid plate and the film is pressurized, peeling the film inward off the island. A model for this inward or “annular” peel indicates that even for systems of good adhesion, peel can be initiated at low enough pressures to prevent film failure by making the center island sufficiently small relative to the size of the film. We have fabricated island blister test sites using micromachining techniques and have used them to measure the debond energy of polymer films on various substrates. The peel data obtained from these island sites match well to the behavior predicted by a simple fracture mechanics analysis. This paper reports the fabrication of the island test sites, the experimental verification of the test, and the results of application of the test to polyimide films on metallic and polymeric substrates. 相似文献
14.
The island blister test has recently been proposed as an adhesion test which allows the peel of thin, well-adhered films without exceeding the tensile strength of the film. The island blister test site is a modification of the standard blister test site, consisting of a suspended membrane of film with an “island” of substrate at the film center. The membrane support and island are secured to a rigid plate and the film is pressurized, peeling the film inward off the island. A model for this inward or “annular” peel indicates that even for systems of good adhesion, peel can be initiated at low enough pressures to prevent film failure by making the center island sufficiently small relative to the size of the film.
We have fabricated island blister test sites using micromachining techniques and have used them to measure the debond energy of polymer films on various substrates. The peel data obtained from these island sites match well to the behavior predicted by a simple fracture mechanics analysis. This paper reports the fabrication of the island test sites, the experimental verification of the test, and the results of application of the test to polyimide films on metallic and polymeric substrates. 相似文献
We have fabricated island blister test sites using micromachining techniques and have used them to measure the debond energy of polymer films on various substrates. The peel data obtained from these island sites match well to the behavior predicted by a simple fracture mechanics analysis. This paper reports the fabrication of the island test sites, the experimental verification of the test, and the results of application of the test to polyimide films on metallic and polymeric substrates. 相似文献
15.
Tsunou Chang Elizabeth A. Sproat Yeh-Hung Lai Nick E. Shephard David A. Dillard 《The Journal of Adhesion》1997,60(1):153-162
The ability to determine the durability of adhesive bonds remains an elusive task, especially when the service environment involves exposure to diluents such as water. Moisture continues to be of major concern for many adhesive bond systems for a number of reasons including:
1) many adhesives are hydrophilic, picking up significant amounts of moisture over time;
2) most adhesives and some adherends allow moisture permeation, eventually reaching the adhesive/adherend interface;
3) the high surface energies of metallic and certain other substrates result in moisture migrating to the adherend surfaces and displacing the adhesive from the substrates, and possibly oxidizing the adherend, etc., and
4) absorbed moisture induces swelling stresses which can reduce the bond strength.
Recognition of this susceptibility to moisture has led to extensive studies aimed at evaluating the effects of moisture, developing an understanding of the responsible mechanisms, and predicting the performance of adhesive bonds subjected to humid environments. While some studies have focused on the effect of humidity on neat adhesive samples, most studies have recognized the significance of the adhesive/adherend interactions, and have evaluated strength of actual bonded joints. Unfortunately, the time required for typical bonded geometries to reach moisture equilibrium can be quite long. Single lap joints (SLJ) and double cantilever beam (DCB) specimens with a width of 25mm may take several years to equilibrate, depending on the temperature and adhesive. Such lengthy conditioning times hamper the development of improved adhesives, and may delay the acceptance of these adhesives because of the time required to certify them. Methods to accelerate the conditioning of test specimens would be of significant benefit to adhesive formulators and users. 相似文献
1) many adhesives are hydrophilic, picking up significant amounts of moisture over time;
2) most adhesives and some adherends allow moisture permeation, eventually reaching the adhesive/adherend interface;
3) the high surface energies of metallic and certain other substrates result in moisture migrating to the adherend surfaces and displacing the adhesive from the substrates, and possibly oxidizing the adherend, etc., and
4) absorbed moisture induces swelling stresses which can reduce the bond strength.
Recognition of this susceptibility to moisture has led to extensive studies aimed at evaluating the effects of moisture, developing an understanding of the responsible mechanisms, and predicting the performance of adhesive bonds subjected to humid environments. While some studies have focused on the effect of humidity on neat adhesive samples, most studies have recognized the significance of the adhesive/adherend interactions, and have evaluated strength of actual bonded joints. Unfortunately, the time required for typical bonded geometries to reach moisture equilibrium can be quite long. Single lap joints (SLJ) and double cantilever beam (DCB) specimens with a width of 25mm may take several years to equilibrate, depending on the temperature and adhesive. Such lengthy conditioning times hamper the development of improved adhesives, and may delay the acceptance of these adhesives because of the time required to certify them. Methods to accelerate the conditioning of test specimens would be of significant benefit to adhesive formulators and users. 相似文献
16.
A flow microcalorimetric technique for characterising the acidities of sulphonated polystyrene resins by ammonia adsorption from the gas phase has been applied to a series of macroporous and gel-type resin catalysts. The relationship between acidities measured using this technique and catalytic activities towards liquid phase reactions has been examined using two acid-catalysed test reactions. Results show that catalytic activities are not related in a simple way to the concentrations of acid sites measured by ammonia adsorption, but there is a useful correlation between the strengths of the acid sites measured in this way and catalytic activities of the resins. We conclude that acid site strength, based on ammonia adsorption and used alone, can be a useful indicator of activity for this type of acid catalyst. 相似文献
17.
简介了ASTM D 4726《室外门窗组装用硬聚氯乙烯(PVC)挤出型材标准》中用于评价PVC型材耐候性的色牢度评价方法,并与EN 12608—2003《门窗用未增塑聚氯乙烯(PVC-U)型材分类、要求和试验方法》、GB/T 8814—2004《门、窗用未增塑聚氯乙烯(PVC-U)型材》、JG/T 263—2010《建筑门窗用未增塑聚氯乙烯彩色型材》、GB/T 3681—2000《塑料大气暴露试验方法》中耐候性评价方面的规定进行了对比,指出色牢度评价方法对于我国PVC型材行业制定同类标准具有很强的借鉴作用。 相似文献
18.
In order to determine the effect of outdoor aging in various areas of the world, poly(vinyl chloride), PVC, compositions were exposed at test sites in Australia, Canada, England, Germany, South Africa, and in Piscataway, New Jersey. These results are related to the climatological data from the different test sites. The data obtained show the effects of a three-year period of exposure on clear and filled, flexible and rigid PVC compositions. The merits of various types of additives are shown in respect to the outdoor aging properties of PVC compounds. It was observed that the exposure conditions vary from severe for Australia and South Africa to mild for England. However, the general results obtained throughout the world correlate well with those from the exposure site in New Jersey. 相似文献
19.
文章叙述1998年~2005年期间经广州电器科学研究院组织,在我国几个大气暴露试验场进行的迈克林电力公司绝缘子用复合绝缘子用硅橡胶伞套材料的大气暴露试验和人工加速光老化试验结果。试验表明,经自然暴露试验后材料的机电性能略有变化。文章主要针对了广州、海南、拉萨和敦煌四地不同气候的地理环境进行暴露,其中在海南暴露其机电性能变化不明显,而西北干燥沙漠地区和亚热带高原地区机电性能变化较大。人工加速气候试验结果表明,其机械性能与加速试验持续时间基本没有关系。此外,还报道了在中国电力科学研究院进行的硅橡胶材料的5000 h多应力试验结果,试验表明性能良好。 相似文献