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胶黏剂是人们在生活工作中经常被使用的工具,但由于生产过程中添加醛类和在使用中会挥发出甲醛造成VOC污染,不仅会刺激人类呼吸道和神经系统,严重会致癌,导致人体畸形。故对胶黏剂中甲醛含量测定具有一定重要性,本文对比了紫外分光光度法和高效液相色谱法对胶黏剂中甲醛含量的测定,得到紫外分光光度法的空白加标回收率为107.89%、样品聚四氟乙烯(PTFE)、氟化乙烯丙烯共聚物(FEP)、聚氨酯(PU)三种胶黏剂加标回收率分别为116.57%、119.34%及114.87%,故经实验后得到紫外分光光度法的回收率和稳定性都更好。 相似文献
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复合薄膜用双组分水性聚氨酯胶黏剂的制备和性能 总被引:2,自引:0,他引:2
制备了复合薄膜用双组分水性聚氨酯胶黏剂,初步研究了两种外加型交联剂环氧树脂6360、三聚氰胺-甲醛树脂对胶黏剂性能的影响。红外谱图和差示扫描量热法分析的结果表明在双组分水性聚氨酯胶黏剂中水性聚氨酯和交联剂发生了交联反应。外加交联剂可增加水性聚氨酯胶黏剂的交联度和黏度,从而有效提高胶黏剂的T型剥离强度和耐溶剂性能。环氧树脂较佳加入量在5%左右而三聚氰胺-甲醛树脂约为10%。由双组分水性聚氨酯胶黏剂黏合的PET/PE薄膜在较高温度下适当处理一段时间,其黏合效果更佳。 相似文献
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以天然可再生资源替代传统化石资源开发绿色环保、性能优异的木材胶黏剂是人造板行业研究的热点。木质素来源广泛、价格低廉,且分子结构中含有羟基、甲氧基、羧基等活性基团,易于功能化修饰,是合成木材胶黏剂的理想原料。本文重点综述了木质素及其衍生物在酚醛树脂、脲醛树脂、环氧树脂、聚氨酯等合成树脂木材胶黏剂中的应用与研究现状,介绍了化学改性、降解、溶剂分级纯化等预处理方式对木质素化学反应活性及合成树脂胶黏剂力学性能的影响,探讨了木质素基木材胶黏剂目前发展面临的困难和挑战,并展望了未来应用及研究方向,以期为木质素资源的高效、高值化综合利用及高性能生物基木材胶黏剂的开发提供理论与技术参考。 相似文献
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脲醛树脂(UF树脂)胶黏剂具有胶合强度高、制作简单、成本低廉、原料来源丰富等一系列特点,成为我国人造板生产的主要胶种,是市场上需求量最大的胶黏剂之一。但由于在固化时会放出刺激性的甲醛,游离甲醛高,在使用时严重危害人的健康。近年来,随着人们环保意识的提高,生产和使用低毒UF树脂胶势在必行。本文介绍了稀土氧化镧对脲醛树脂的改性过程并对改性后脲醛树脂胶的各项性能进行了测试。本实验通过在不同反应阶段加入稀土氧化镧,分别探讨它们对脲醛树脂胶黏剂性能影响。实验表明:在脲醛树脂胶中加入稀土氧化镧可以增加黏度、固化时间、固含量,并可以减少游离甲醛释放量。 相似文献
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聚乙烯热熔胶增容聚乙烯基木塑复合材料的研究 总被引:3,自引:0,他引:3
采用废木粉和高密度聚乙烯制备复合材料,并采用一种聚乙烯热熔胶作为相容剂以增进憎水性的聚乙烯基材和亲水性的木粉界面的相互作用。评价了该热熔胶的增容效果,并对其增容机理进行了详细论述。研究结果表明:该热熔胶的主要成分为马来酸酐接枝高密度聚乙烯(PE-HDg-MAH)和乙烯-醋酸乙烯酯共聚物(EVA);添加木粉有利于弯曲强度和弯曲模量的提高,但使冲击强度和拉伸强度迅速下降;该热熔胶可明显提高复合材料的力学性能,并且木粉的填充量越高,则增容作用就越明显;当木粉的用量为50%时,使用该热熔胶可使复合材料的拉伸强度、弯曲强度、弯曲模量和冲击强度分别提高115.6%、66.7%、38.1%和67%;基于这些结果可知,该热熔胶可显著提高聚乙烯基材/木粉界面处的亲和力,是聚乙烯基木塑复合材料理想的增容剂。 相似文献
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Duration of wood preweathering: Effect on the service life of subsequently applied paint 总被引:1,自引:0,他引:1
Previous studies of the effect of preweathering of wood (weathering of wood prior to painting) on subsequent paint performance
have not linked short periods of preweathering (weeks) to paint service life. To examine the link between preweathering and
paint service life, we analyzed paint performance (cracking and flaking) after 14 years outside on boards that were preweathered
for various amounts of time. We then compared our results with previous results from paint adhesion tests of similar boards
that were also preweathered for the same amount of time. There was a direct correlation between the amount of time the siding
was preweathered and the long-term performance of paint. Paint on wood preweathered for 16 weeks began to fail after just
three years. Paint on wood preweathered for shorter periods lasted longer, but even those boards that were preweathered for
as little as one week showed paint failure earlier than boards that were not preweathered. There was also good correlation
between paint adhesive strength results from the previous study and outdoor paint performance results from this study, showing
that loss of paint adhesion may be linked to paint performance in outdoor field tests.
Forest Products Laboratory, One Gifford Pinchot Dr., Madison, WI 53705-2398. 相似文献
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In a full-scale mill experiment two groups of high density wood fibre boards were produced. While one group was bonded with a standard melamine reinforced urea-formaldehyde adhesive, a second group was bonded with a modified adhesive yielding systematically improved board properties at identical amounts of adhesive applied. By means of a novel fluorescence-microscopic method using the dye Acriflavine to colour the cured adhesive after board production, adhesive distribution within the industrial produced boards was evaluated and quantified. Very clear differences in the size distribution of the two adhesives were found, leading to the conclusion that a relationship exists between adhesive distribution and mechanical board performance. 相似文献
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介绍了金属--塑料复合板用无溶剂聚氨酯胶粘剂的合成方法,讨论了原料配比、反应温度、水含量、(-NCO)/(-OH)的配比对胺粘剂性能和剥离强度的影响。 相似文献
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This paper presents a new application of Automated Bonding Evaluation System (ABES) for studying the reactivity of adhesive–substrate combinations (adhesive–cork, impregnated paper–wood and laminate–wood); a new sample configuration and a new kinetic model are proposed. Isothermal bond strength development was plotted as a function of time for several platen temperatures and the kinetic parameters were computed from these plot families, for each type of adhesive and combinations. The methodology developed showed to have potential in quantitative screening of adhesives and operating conditions in industrial context (production of cork composites, melamine faced boards and high pressure laminates). 相似文献
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淀粉在木材胶粘剂中的应用 总被引:1,自引:0,他引:1
介绍了淀粉在木材胶粘剂中的应用,主要论述了淀粉作为改性剂可以有效地改善脲醛树脂胶的预压及胶合性能,可以加快聚醋酸乙烯酯的固化速度及提高耐水性。以淀粉为原料合成木材用胶粘剂主要通过加入异氰酸酯、三聚氰胺和苯酚衍生物改性或将淀粉氧化成双醛淀粉通过缩聚改性。 相似文献
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醇溶性丙烯酸酯胶粘剂的研究 总被引:2,自引:2,他引:0
采用溶液聚合法合成了一种高固含量、低黏度的醇溶性丙烯酸酯胶粘剂,研究了软硬单体配比、溶剂种类、聚合工艺以及松香树脂含量等对该胶粘剂性能的影响。研究结果表明,以乙醇/乙酸乙酯为混合溶剂,当m(软单体)∶m(硬单体)≈2.0∶1、W(功能单体丙烯酸)=4%(相对于总单体而言)、反应温度≈73℃、反应时间≈7 h、W(单体)≈50%(相对于反应物料而言)和m(醇溶性丙烯酸酯共聚物溶液)∶m(50%松香溶液)=5∶1时,醇溶性胶粘剂的综合性能最佳;可作为透明材料(如BOPP/CPP)、镀铝材料(如BOPP/镀铝CPP)和珠光膜材料(如BOPP/珠光膜)的复膜胶。 相似文献