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71.
高性能环氧树脂涂料的研制   总被引:1,自引:0,他引:1  
以甲基丙烯酸、丙烯酸丁酯及苯乙烯的聚合为接枝体,在过氧化苯甲酰作用下对E-51环氧树脂进行接枝改性,同时对三乙烯四胺进行曼尼希改性,制得多种改性固化剂,并用其与改性的环氧树脂配制成涂料,实验结果表明,当苯酚、甲醛和三乙烯四胺的物质的量比为3:3:1时固化剂的固化性能最好。  相似文献   
72.
环氧树脂的改性研究进展   总被引:7,自引:0,他引:7  
概述了近年来利用互穿网络法、液晶增韧法、纳米粒子增韧等改性环氧树脂的新方法。  相似文献   
73.
在季铵盐催化作用下 ,甲基丙烯酸与环氧氯丙烷反应生成甲基丙烯酸缩水甘油酯。实验结果表明 ,二步法可获得较高的产率  相似文献   
74.
Atomic force microscopy (AFM) has been used to study the morphology and microstructure of an amine-cured epoxy before and after outdoor exposure. Measurements were made from samples prepared in an essentially CO2-free, H2O-free glove box and from samples prepared in ambient conditions. For those prepared in a CO2-free glove box, AFM imaging was conducted on (1) an unexposed air/coating surface, (2) an unexposed coating bulk, (3) an unexposed coating/substrate interface, and (4) a field exposed air/coating surface. For samples prepared in ambient conditions, only the unexposed air/coating surface was investigated. The same regions of the exposed samples were scanned periodically by the AFM to monitor changes in the surface morphology of the coating as UV exposure progressed. Small angle neutron scattering and Fourier transform infrared spectroscopy (FTIR) studies were performed to verify the microstructure and to follow chemical changes during outdoor exposure, respectively. The results have shown that amine blushing, which occurs only under ambient conditions, had a significant effect on the surface morphology and microstructure of the epoxy. The surface morphology of the samples prepared under CO2-free, dry conditions was generally smooth and homogeneous. However, the interface and the bulk samples clearly revealed a two-phase structure consisting of bright nodular domains and dark interstitial regions, indicating an inhomogeneous microstructure. Such heterogeneous structure of the bulk was in good agreement with results obtained by small angle neutron scattering of unexposed samples and by AFM phase imaging of the degraded sample surface. The relationship between submicrometer physical changes and molecular chemical degradation is discussed. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   
75.
胡高平  肖卫东 《粘接》2005,26(5):19-20
在环氧-聚酰胺体系中分别加入“海岛结构”QS-1、聚硫橡胶、液体丁腈橡胶增韧改性,通过对固化物剪切强度、弯曲弹性模量及断裂强度的对比,“海岛结构”QS-1增韧综合性能较好.  相似文献   
76.
In this paper we describe an apparatus for reproducibly measuring thermal shock resistance of thick polymer layers bonded to metals. The thermal shock behavior is discussed in terms of epoxy samples bonded to an aluminum substrate. It was found that both high resin toughness and low resin thermal expansion coefficient improved thermal shock resistance of thick coatings, but only a sample containing 60wt. % glass beads did not develop a failure crack. Effects of sample thickness, temperature gradient, and resin composition on thermal shock behavior are discussed.  相似文献   
77.
核设施、设备用耐高温涂料的研制   总被引:4,自引:2,他引:4  
采用自制的环氧改性有机硅树脂和聚酰胺树脂为交联固化体系,加入锌粉、陶瓷粉和特种功能体质颜料,通过合理优化匹配制得的涂料不仅具有优异的机械性能、防腐性能,而且能长期耐高温、耐辐射,并具有很好的去污性能。  相似文献   
78.
The properties of poly(vinyl acetate) compositions prepared as potential wood adhesives were investigated. The paper presents the results of the influence of various kinds of inorganic fillers based on calcium carbonate and alumino-silicate and an organic filler, starch, on the adhesive composition properties. The comparison among rheological behavior of the adhesive dispersions concerning the specific role of fillers were made. Mechanical and relaxation properties of the adhesive films could reveal the effect of filler characteristics on the polymer matrix. The significant influences of particle size distribution and specific surface area on the poly(vinyl acetate) adhesive composition were determined, along with other filler characteristics.  相似文献   
79.
通过大量的试验研究,设计了一个合理的环氧富锌车间底漆配方,制备出的涂料漆膜性能符合国家标准,且降低了涂料整体的污染程度。  相似文献   
80.
Epoxy adhesives filled with four different volume fractions of eutectic tin-bismuth solder alloy were prepared and the effect of filler content on the electrical and mechanical properties of these anisotropic electrically conductive adhesives was investigated. The results show that the adhesive containing the lowest amount of the filler alloy had the best combination of conductivity, insulation resistance and shear strength. The DSC-measurements suggested that the filler melts before the cure of the resin begins which allows the filler to wet and bond well to the conductors. This was verified by SEM/EPMA examinations. A temperature cycling test and high humidity, high temperature treatment were conducted on the best composite adhesive. The temperature variation had no effect on conductivity of the joints while humid and hot environment decreased the conductivity.  相似文献   
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