共查询到20条相似文献,搜索用时 80 毫秒
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水性环氧改性聚氨酯涂料的研制 总被引:36,自引:4,他引:36
通过环氧树脂与聚氨酯的接枝反应,合成了环氧改性聚氨酯乳液,用其配制综合性能良好的水性环氧改性聚氨酯涂料,适用于木地板涂装,使用效果好。讨论了NCO/OH比值、环氧树脂加量和残留异氰酸根的量对涂料性能的影响。 相似文献
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《涂料工业》2015,(5)
采用二乙醇胺对双酚A型环氧树脂进行开环,再以甲乙酮肟为封闭剂,对聚氨酯预聚体的端—NCO基进行部分封闭,再结合开环后的环氧树脂,合成了一种稳定性良好、防腐性能优异的封闭型聚氨酯-环氧树脂复合乳液。研究了环氧树脂开环剂、聚氨酯预聚体的封闭程度以及环氧树脂用量对乳液和涂膜性能的影响,通过电化学方法和浸泡腐蚀实验研究了涂膜的防腐性能。结果表明:开环后的环氧树脂能显著提高乳液的稳定性,而耐腐蚀性变化不大;聚氨酯预聚体封闭程度为40%~43%时聚合物的交联度合适,乳液性能优异;随着环氧树脂用量增加,乳液粒径先减小后增大,涂膜防腐性能逐渐提高,且远优于非封闭型聚氨酯-环氧树脂成膜体系;环氧树脂用量可达24%左右。 相似文献
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在制备水性聚氨酯基础上引入了环氧树脂,制得了水性环氧改性聚氨酯乳液。环氧树脂的引入增加了水性聚氨酯的交联结构,与改性前的水性聚氨酯相比,其涂膜耐水性、耐溶剂性以及机械性能都得到了提高。并研究了环氧树脂的引入方法及环氧树脂加入量对分散体及其涂膜性能的影响。傅里叶红外光谱分析显示出了环氧树脂与水性聚氨酯之间存在化学键的连接... 相似文献
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环氧树脂/有机硅复合改性聚氨酯阻燃涂料的研究 总被引:2,自引:0,他引:2
采用正交试验法,以涂膜的力学性能和耐燃时间为依据,确定了制备环氧树脂/有机硅复合改性聚氨酯阻燃涂料时,环氧树脂与有机硅的配比,阻燃剂聚磷酸铵、三聚氰胺、季戊四醇的最佳用量。对涂膜进行了红外光谱和热重分析,对比检测了未改性聚氨酯涂料和环氧树脂/有机硅复合改性聚氨酯阻燃涂料的各方面性能。结果表明,环氧树脂/有机硅复合改性聚氨酯阻燃涂料的涂膜具有较高的拉伸强度,热稳定性能良好,防火阻燃性能优良。 相似文献
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采用溶液聚合的方式,以香草醛、对苯二胺、二苯基甲烷二异氰酸酯(MDI)、二聚三乙二醇为单体,制备了一系列席夫碱结构的液晶聚氨酯(LCUn),并利用差示扫描量热仪(DSC)、偏光显微镜(POM)探究了其液晶性能。结果表明,所制备的液晶聚氨酯呈现了典型的向列相织构。利用液晶聚氨酯与环氧树脂共混制备了复合材料,通过红外图像系统观察了液晶聚氨酯在环氧树脂中的分布状态,发现其在环氧树脂基体中形成了有序区域。探究了液晶聚氨酯含量与复合材料性能之间的关系,结果表明环氧树脂的力学性能获得提高。 相似文献
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以甲苯二异氰酸和聚丙二醇等为原料对普通的环氧树脂进行改性研究,考察了PU含量对环氧树脂耐热性、韧性等的影响。通过红外光谱、SEM、热重分析和流变性等方式对合成的聚氨酯改性环氧树脂进行了性能的表征和检测。红外光谱测试结果表明聚氨酯的-NCO和氨基甲酸酯中-NH均与环氧基发生了反应,可断定聚氨酯成功与环氧树脂嫁接;热重分析结果表明聚氨酯改性环氧树脂耐热性强于环氧树脂;粘度测试结果表明改性后环氧树脂流动性变好;SEM结果表明改性后环氧树脂的断面银纹增多、韧性增强。 相似文献
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《The Journal of Adhesion》2007,83(1):1-14
The durability of epoxy-aluminium joints that use a homopolymerised epoxy resin was studied, and the effects of relative humidity, temperature, and salt concentration were analysed. The adhesive properties were measured by lap-shear tests, and the water uptake of the epoxy resin was determined by gravimetric measurements. Ageing and degradation effects on the epoxy resin and on the aluminium substrates were also analysed.
The homopolymerised epoxy resin absorbs little water (1.5 wt%) because of its nonpolar network structure. The water uptake is enhanced by increasing relative humidity and temperature; however, the joint strength remains constant because of epoxy plasticization. A saline environment is damaging to the adhesive joints, because of metal corrosion, but was not significantly harmful to the epoxy resin, because of a lower diffusion coefficient of salt water. The Tg decrease of the epoxy adhesive due to water absorption depends only on the amount of absorbed water and is independent of the hydrothermal ageing conditions. 相似文献
The homopolymerised epoxy resin absorbs little water (1.5 wt%) because of its nonpolar network structure. The water uptake is enhanced by increasing relative humidity and temperature; however, the joint strength remains constant because of epoxy plasticization. A saline environment is damaging to the adhesive joints, because of metal corrosion, but was not significantly harmful to the epoxy resin, because of a lower diffusion coefficient of salt water. The Tg decrease of the epoxy adhesive due to water absorption depends only on the amount of absorbed water and is independent of the hydrothermal ageing conditions. 相似文献
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环氧树脂纳米蒙脱土胶粘剂耐蚀性能研究 总被引:3,自引:1,他引:3
研究了水泥、蒙脱土(有机化和未有机化)和粉煤灰作为填料在环氧树脂胶粘剂涂层中的作用,讨论了不同填料对胶粘剂的耐蚀性能的影响。试验采用的腐蚀介质有自来水、氢氧化钠水溶液、氯化钠水溶液和盐酸溶液。试验结果表明加入有机化蒙脱土的环氧树脂胶粘剂,在无介质,强酸和强碱环境中,都具有较好的拉伸剪切强度。推荐了在不同介质条件下的胶粘剂的使用配方。 相似文献
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Yanchao Zhu Bing Di Hongzhuo Chen Xiaofeng Wang 《Journal of Adhesion Science and Technology》2019,33(16):1806-1820
Novel biomass lignin/silica composites were prepared and isolated from rice husk renewable resources at different pHs. Selective precipitation was achieved by decreasing the solution pH from 9.5 to 1.5. When pH reached 3.5, the ratio of lignin and silica mostly achieved the maximum of 1:1. We selected lignin/silica composites as reactants to replace 20?wt% bisphenol A in preparing epoxy resin. The cured novel biomass function lignin/silica-based epoxy resin adhesive showed the highest adhesive strength up to 2.68?MPa, which displayed 123% of neat epoxy resin adhesive. In addition, lignin/silica composites were depolymerized through the hydrothermal method by NaOH as a catalyst, which was used as reactants to replace 35?wt% bisphenol A in the process of in situ synthesis of epoxy resin adhesive. At this point, the high epoxy value (1.42?wt%) and large adhesive strength (3.98?MPa) of lignin/silica-based epoxy resin adhesive were obtained, which adhesive strength was 183% of neat epoxy resin adhesive. The results demonstrated that depolymerized lignin/silica-based epoxy resin adhesive showed the higher epoxy value and the adhesive strength compared with neat epoxy resin adhesive and lignin/silica-based epoxy resin adhesive. Their function in epoxy matrix resulted in better processability. 相似文献
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The effect of the exposure time in water on the adhesive strength of fiber/resin systems was studied. To this end, the adhesive strength of single-fiber/matrix systems was measured. Such a system simulates the unit cell of a fiber-reinforced composite. The resin was an epoxy (DGEBA-based) polymer. The substrate used consisted of boron fibers, a steel wire and glass fibers. The samples were kept in water for a period of 1-280 days at room temperature and the adhesive strength was measured also at room temperature. The water absorption of the resin and the impregnated strand produced on the basis of the glass fibers and the resin studied and also the physico-mechanical characteristics of the impregnated strand were studied at the same time. The samples used to determine the adhesive strength were kept in such a contact with water that the latter could penetrate into some of them only at the interface and into the others at the interface and through the resin layer.
It was found that the adhesive strength decreases with increasing amount of water absorbed. On the basis of the results obtained it was concluded that the principal factor that determines the loss in adhesive strength during the aging of the systems in water is the plasticization of the epoxy resin by water. 相似文献
It was found that the adhesive strength decreases with increasing amount of water absorbed. On the basis of the results obtained it was concluded that the principal factor that determines the loss in adhesive strength during the aging of the systems in water is the plasticization of the epoxy resin by water. 相似文献
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采用异佛尔酮二异氰酸酯(IPDI)、聚己二酸丁二醇酯(PBA)、二羟甲基丙酸(DMPA)、环氧树脂等原料制备了层压复合用水性聚氨酯(WPU)胶粘剂,考查了环氧树脂用量对其性能的影响。结果表明,随着环氧树脂用量的增加,WPU乳液黏度增加,粒径逐渐变大,稳定性变差;经环氧树脂改性的WPU,胶膜的耐水性优于未改性胶膜,力学性能得到提高。 相似文献
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An epoxy resin was blended with a diallyl phthalate resin to improve the adhesive properties and the fracture toughness. A compatibilizer was used to reduce the decrease in heat resistance. An allyl ester compound [1,4‐diallyloxycarbonyl‐2,5‐benzenedicarboxylic acid (DAPY)], which reacted with the diallyl phthalate resin and epoxy resin to have allyl groups and carboxylic acids on the end of the molecular chain, was synthesized as a compatibilizer by the reaction of pyromellitic dianhydride with allyl alcohol. These blends were cured with dicumyl peroxide and triethylamine. By modification with the epoxy resin and DAPY, the lap shear adhesive strength to steel increased up to about 3 times that of the diallyl phthalate resin. These results suggest that the secondary hydroxyl group generated by the addition reaction of the epoxy resin and DAPY and the secondary hydroxyl group existing in the molecular chain of the epoxy resin formed hydrogen bonds with the hydroxyl group of water existing on a metal surface, and as a result, the adhesive strength to metal such as steel increased. The fracture toughness of the diallyl phthalate resin was increased by modification with the epoxy resin. The reason for this result was that the flexibility increased because the crosslinking density became small by modification with the epoxy resin. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献