甲醛系木材胶粘剂

<正> 木材胶粘剂是一类籍助于表面附着将木材与木材或木材与其它材料胶合成一体的物质。通常包括酚醛树脂胶,脲醛树脂胶、三聚氰胺树脂胶、间苯二酚树脂胶、单宁胶、木素胶、多异氰酸酯胶、聚乙酸乙烯酯乳液以及植物蛋白胶、动物蛋白胶、淀粉胶等。其中最主要的是上列前三种,又合称三醛胶,它们都是由甲醛为主要原料合成的。这些胶粘剂,除了主体     

乳白胶木材胶粘剂的制备试验

本文介绍了木材粘合常用的两种合成树脂乳白胶和脲醛树脂的制备配方和工艺,叙述了用正交表进行乳白胶木材胶粘剂配方设计的试验情况。试验结果表明:(1)所述8个乳白胶胶粘剂配方粘合木材的剪切强度均大于1.96MPa,成本比较低廉;(2)所选定的增塑剂DBP用量对粘合强度影响特别显著,应当重视乳白胶胶粘剂中增塑剂总含量的选择;(3)根据正交表的方差分析确定胶粘剂的最优配方是A_2B_1C_1D_1。     

花生壳制木材用胶粘剂的研究

对花生壳的组份作了较为详细的研究，同时从利用花生完全组份的观点出发，对花生壳的制胶工艺作了改进，使花生亮能１００％地用作制胶的原料。     

木材工业用胶粘剂的现状及发展趋势

主要介绍了脲醛树脂、酚醛树脂、三聚氰胺－ 甲醛树脂、木质素、单宁、异氰酸酯等木材工业用胶粘剂的研制状况及发展趋势。     

木质素在人造板胶粘剂中的应用

作为地球上最丰富的可再生资源之一，木质素是制浆造纸工业的副产物之一，若得不到充分利用，则不仅造成严重的环境污染，而且导致巨大的资源浪费。因此，如何有效地利用木质素这种可再生资源已成为科研工作者研究的出发点。本文主要就木质素在人造板胶粘剂中的应用作以总结，旨在推动木质素胶粘剂工业化生产与应用的进程。     

低甲醛释放木材胶粘剂研究进展

我国已成为世界人造板生产大国,木材胶粘剂年用量已超过400万t,其主要胶种为甲醛类合成树脂胶粘剂.本文评述了木材胶接用甲醛类合成树脂胶粘剂的开发研究、生产应用及发展,重点综述了低甲醛释放的脲醛树脂、三聚氰胺-尿素共缩合树脂和酚醛树脂胶粘剂的研究进展和开发应用情况,并对其发展趋势等进行了展望.     

天然可再生资源在木材胶粘剂中的应用

综述了木素、单宁、大豆蛋白、淀粉、壳聚糖等天然可再生资源在木材胶粘剂中的应用。     

MMF胶粘剂的研究

MMF胶粘剂是一种改性的三聚氰胺甲醛(MF)浸渍树脂,具有生产成本低、不使用乙醇溶剂、易脱模的显著优点,已成功地用于装饰板的生产。胶和装饰板的性能均符合相应标准。本文研究了影响胶粘剂质量的各种因素。     

我国木材胶粘剂发展概况

综述中国木材胶粘剂概况．报告了脲醛树脂、酚醛树脂、三聚氰胺－甲醛树脂、单宁胶、本素胶、木材的本体聚合等胶粘剂与粘合技术的改进，并提出有关建议。     

我国胶粘剂市场及“十二五”发展规划

2009年,我国胶粘剂及密封剂产量为405万吨,销售额526亿元,分别比2008年增长13．44％和8.45％（其中脲醛、酚醛和三聚氰胺甲醛胶粘剂未统计在内）,见表     

生物基木材胶粘剂

具体介绍了几种重要生物基木材胶粘剂,包括木素、单宁、大豆蛋白、淀粉、木质生物质液化产物胶粘剂、热解生物油胶粘剂等的研究进展情况。分析了生物基木材胶粘剂的应用现状,指出了生物基木材胶粘剂存在的问题,并对其发展方向进行了展望。     

木材胶粘剂的研究进展

介绍了三醛胶和白乳胶的改性研究进展,综述了近年来出现的新胶种以及可再生资源在胶粘剂中的利用,并对木材胶粘剂的发展进行了展望.     

Glutaraldehyde-wheat gluten protein adhesives for wood bonding

ABSTRACT

Wheat gluten protein hydrolysate was used as a biomass feedstock to prepare environmentally friendly protein-based adhesives, with hydrolyzed wheat protein as control. Glutaraldehyde was used to modify it to obtain a glutaraldehyde-wheat protein (GP) adhesive. Polyethylenimine (PEI) was also used as a crosslinking agent. Plywood has been prepared and tested, and its performance was used to measure the wheat gluten protein hydrolysate adhesive bonding performance. Differential scanning calorimetry (DSC) and thermomechanical analysis (TMA) were used to analyze the adhesive thermal properties and the microstructures of the cured adhesives by scanning electron microscopy (SEM). The results show that modification by glutaraldehyde can effectively improve the bonding performance of wheat protein adhesives, the plywood bonded strength having been improved by its addition. The effect of PEI as a crosslinking agent became evident. It can greatly improve the bonding properties of glutaraldehyde-modified wheat protein adhesives. TMA analysis indicates that the glutaraldehyde-modified GP adhesive has a higher storage modulus than the unmodified one. The modulus of the adhesive increased after adding the PEI cross-linking agent.     

乙烯基乳液-异氰酸酯木材胶粘剂的研究

介绍了一种乙烯基乳液－异氰酸酯木材胶粘剂,探讨了配方中主要成分对胶粘剂性能的影响。该胶具有良好的胶接性、耐水性。     

Morphologic accessibility of wood adhesives

Accessibility of wood adhesives was determined using a potassium bromide-embedding technique during resin cure. Cured resin was then extracted with water, followed by x-ray analysis of residual potassium bromide retention in the adhesive matrix. Cured urea–formaldehyde (UF), phenol–formaldehyde resol (PF), and phenol–resorcinol formaldehyde (PRF) accommodated large quantities of potassium bromide. However, only PRF adhesive showed crystallization of trapped potassium bromide, suggesting the presence of large pore sizes in the polymer lattices. Both UF and PRF adhesives, after room-temperature soaking, were equally resistant to water access. At higher temperature, water accessibility of UF increased greatly which may be attributed to thermal softening of the adhesive, while the accessibility of water to the PRF adhesive matrix was mainly a surface phenomenon and was not very temperature dependent. PF was highly accessible to water, even at room temperature, as a result of swelling from the presence of sodium hydroxide (catalyst). Accessibility of PRF adhesive was greatly increased by base (NaOH) solutions but not by acid (H₂SO₄) solutions. The UF resin showed slight increase of accessibility with increase in acidity and basicity of the water solution, but the accessibility increase of this adhesive in base solution was substantially less than that of PRF. The acid hydrolysis influence on accessibility increase of UF adhesive was far less severe than that of temperature.     

Investigation of epoxy-based wood adhesives

Cold-set epoxy-based wood adhesives were investigated for production of exterior plywood. Effective adhesives were composed of bisphenol A diglycidyl ether (BPADGE), polyamidoamine (PAA), and polyethylenimine (PEI). Three-ply plywood panels were prepared with BPADGE–PAA–PEI adhesives and evaluated for their strengths and water resistance in accordance with a standard for exterior plywood. The effect of BPADGE/(PAA + PEI) weight ratio, PAA/PEI weight ratio, the mixing time for preparing the adhesive, and the pressing time for making plywood panels on the water resistance and the shear strengths of the plywood panels was investigated. The pot life of the adhesive was also measured. Plywood panels made with the BPADGE–PAA–PEI adhesives met the industrial requirements for exterior applications. Adhesion mechanisms are discussed in detail. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47741.     

木材胶粘剂用丙烯酸酯共聚乳液的研究

研制一种丙烯酸酯共聚乳液配制成水性双组分胶粘剂——丙烯酸酯共聚乳液/异氰酸酯木材胶粘剂,这种水性聚合物—异氰酸酯胶粘剂具有优异的耐水性和耐沸水性能,它是采用在含活性氢原子的聚合物乳液中加入异氰酸酯化合物交联剂的方法合成,用于集成材等木材粘接,可常温快速固化,使用方便、环境友好,具有优异的胶接性能和耐水性能,能够满足日本集成材检测标准和国家林业行业标准。     

传统木材胶粘剂的改性研究进展

本文介绍了脲醛胶、酚醛胶、三聚氰胺一甲醛胶和白乳胶等传统胶种的低醛改性研究进展，并对木材胶粘剂的发展进行了展望。     

Bacterially derived biopolymers as wood adhesives

The wood adhesive market is very large and problems due to volatile organic compounds and toxic chemicals in many adhesives and their production are significant. In addition, most of the adhesives are derived from depleting petrochemical resources. An environmentally friendly wood adhesive based on renewable resources and produced by microbial fermentation has been explored. Using the shear block test method, a microbially produced polysaccharide has been tested and the effects of wood type, humidity, set time, partial acetylation, and surface wetting agents were determined. Shear strength of the microbial polysaccharide adhesive was compared to that of a commercial wood adhesive and other polysaccharides. Shear strengths of up to 20 MPa (3000 psi) for bonding maple have been obtained at 53% relative humidity and 22°C.