大豆蛋白木材胶粘剂的研究进展

近年来,在合成高分子胶粘剂受到环保与成本的双重困扰日益显著的背景下,开发新一代环保可持续的木材胶粘剂已刻不容缓。大豆蛋白胶粘剂作为最具应用潜力的天然胶粘剂之一,已经得到了广泛的研究。综述了几种对大豆蛋白进行改性的常用方法,并对大豆蛋白胶粘剂的发展方向进行了展望。     

硅烷偶联剂提升胶粘剂和粘接性能卓有成效

介绍了有机硅烷偶联剂的结构特点;概述了近年来硅烷偶联剂在胶粘剂和粘接技术方面的应用效果;指出了悉心采用硅烷偶联剂则是胶粘剂和粘接性能改善的有效途径。     

木材工业用酚醛树脂胶粘剂的快速固化研究

从酚醛树脂胶粘剂的配方改进、胶粘剂合成工艺改进、催化剂添加、胶粘剂调胶及人造板热压工艺改进等几个方面,综述了近几年来木材工业用酚醛树脂胶粘剂快速固化研究。     

淀粉基木板胶粘剂的研究进展

淀粉基胶粘剂是胶粘剂“绿色化学”的一个重要发展方向,阐述淀粉及其衍生物在木板胶粘剂中的制备和应用进展,认为淀粉基胶粘剂的耐水性、防腐性及其稳定性仍是当前亟待解决的问题。     

生物质材料木材胶粘剂的研究进展

大豆蛋白作为一种廉价、易得、资源丰富、环境友好的生物质材料受到了广泛的关注,为了解决豆蛋白胶自身易水解、易受微生物侵蚀的缺陷,化学改性豆蛋白被广泛采用,以贻贝胶为模板对豆蛋白、木素等生物质材料进行化学改性用于制备木材胶粘剂也是研究的热点,本文对这2方面的研究进展做了简要的回顾。     

木材胶粘剂的研究现状和发展趋势

本文综述了木材胶粘剂的国内外现状；论述了各种木材胶的结构及作用机理，结合各胶种的优缺点介绍了其应用情况，重点讨论了水性聚氨酯胶粘剂作为木材胶的特点及优势：指出了我国木材加工领域用胶存在的问题和发展趋势。     

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。     

热硫化型橡胶-金属胶粘剂的研究进展

综述了热硫化型橡胶-金属胶粘剂的发展过程及研究现状,分析了不同粘接技术的优缺点;探讨了橡胶-金属粘接过程、原理及构成胶粘剂体系的主要成分,并对橡胶-金属胶粘剂发展趋势进行了展望。     

豆基蛋白质胶粘剂改性及应用研究

为了降低豆基蛋白质胶粘剂的黏度、提高胶合板的耐沸水胶接强度和满足工业化的生产要求,对传统豆基蛋白质胶粘剂进行改性,并通过胶粘剂的黏度、pH值、凝胶时间、耐沸水胶接强度以及热分析结果等确定了改性剂的合理用量。然后以热压温度、热压时间、热压压力和涂胶量作为试验因素,以胶接强度作为考核指标,采用正交试验法优选出制备胶合板用改性豆基蛋白质胶粘剂的较佳工艺条件。结果表明:改性剂的合理用量(质量分数)是40%;胶合板的较佳热压工艺参数是热压温度140℃,热压时间5 min,热压压力1.2 MPa,双面涂胶量310 g/m2;在此较佳热压工艺条件下制备的胶合板,其耐沸水胶接强度较理想(为1.12 MPa),并且满足Ⅰ类胶合板的标准要求。     

一种木材粘合剂胶接强度新型试验装置的研制

设计了一种由基础框架、加载液压千斤顶、测力弹簧、读数百分表和试样夹具组成的木材粘合剂胶接强度试验装置。有限元数值分析与通用材料试验机的测试比较结果表明：该装置可满足JIS K6852标准的要求，且具有结构简单、体积小、测量可靠和便捷的特点。     

Effects of phosphorus-containing additives on soy and cottonseed protein as wood adhesives

Soy and cottonseed proteins appear promising as sustainable and environment-friendly wood adhesives. Because of their higher cost relative to formaldehyde-based adhesives, improvement in the adhesive performance of proteins is needed. In this work, we evaluated the adhesive properties of soy and cottonseed protein formulations that included phosphorus-containing acids and esters. For cottonseed protein isolate, most of these additives improved dry adhesive strength, with methylphosphonic acid, phosphorous acid, and phosphoric acid increasing the dry strength by 47, 44, and 42%, respectively, at their optimal concentrations. For soy protein isolate, these additives did not show significant benefits. The phosphorus-containing additives also improved the hot water resistance of the cottonseed protein formulations but showed either no effect or a negative effect for the of soy protein formulations. Thus, the combination of cottonseed protein with phosphorus additives appears to be attractive as wood adhesives.     

葛根淀粉基胶黏剂制备与性能研究

研究开发以淀粉为主要原料的环保型胶黏剂替代"三醛类"木材胶黏剂,对彻底解决人造板及其制品的甲醛释放问题具有重要意义。以野生葛根淀粉为原料,通过降黏处理,并与聚醋酸乙烯酯和异氰酸酯复配,制备出胶合强度达到国家Ⅱ类要求的淀粉基木材胶黏剂。研究了降黏剂用量、降黏时间、聚醋酸乙烯酯和异氰酸酯用量对淀粉基木材胶黏剂胶合强度的影响。优化工艺条件下制备胶黏剂胶接胶合板的胶合强度为1.89 MPa,能够满足国家Ⅱ类胶合板强度要求。     

Adhesive bonding of 3D-printed ABS parts and wood

Additive manufacturing, also known as 3D printing technology, has experienced massive growth in the last decade. Instead of printing the entire product, 3D printing can be used to produce only the most complex parts, which are then combined with simple, non-printed parts from other materials to make the final product. In addition to mechanical connections, adhesive bonding is most commonly used to combine printed parts with other elements. In this study, the influence of 3D-printing parameters on the bond shear strength of 3D-printed Acrylonitrile-butadiene-styrene copolymer parts bonded to beech wood was investigated. Three printing settings with different layer thicknesses (0.39, 0.19, 0.09 mm) and a posttreatment method that utilized acetone vapour were used. The three different adhesives applied were commercial one-component polyurethane adhesive, hot melt adhesive for edge bonding, and a two-component polyurethane adhesive. The results show that the type of adhesive had the biggest influence on the strength of the bond. The highest bond strength was achieved using a two-component polyurethane adhesive. The type of failure (failure in wood, plastic, adhesive, or cohesive failure) depended greatly on the type of adhesive and thickness of the printed layer.     

Adhesive bonding of acetylated wood

Eighteen thermoplastic and thermosetting adhesives, including emulsion polymer-isocyanates, polyurethane, moisture-curing hot-melt, polyvinyl acetates, neoprene and waterborn contacts, casein, epoxy, melamine, ureas, resorcinol, phenol-resorcinols, and phenolics, were tested for their adhesion to yellow-poplar wood acetylated to 0, 8, 14 and 20 weight percent gains. Effectiveness of adhesion was determined by measuring shear strength and wood failure in a dry condition and after saturation with water. Adhesion was reduced to varying degrees in proportion to the compatibility of the adhesive with the amount of non-pollar, hydrophobic acetate groups in the acetylated wood. Seven of the adhesives developed bonds of high integrity at all levels of acetylation when tested in the dry condition. Two room-temperature-setting adhesives, one a resorcinol-formaldehyde and the other a phenol-resorcinol-formaldehyde, together with a hot-setting acid-catalysed phenol-formaldehyde, developed bonds of high strength and resulted in wood failure at all levels of acetylation when tested in the water-saturated condition.     

Evaluation of wood bonding performance of water-washed cottonseed meal-based adhesives with high solid contents and low press temperatures

Water-washed cottonseed meal (WCSM) has been shown as a promising bio-based wood adhesive. In this work, we tested the bonding strength of WCSM slurries with high solid contents and low press temperatures per industrial input for non-structural applications as European Standard Class D1 wood adhesives. Increasing the WCSM content from 11 to 20% and 30% did not substantially change the adhesive strength but increased the viscosity of WCSM slurries dramatically. The shear strength at break of the maple wood pairs bonded at 40 and 60 °C was lower than that of maple pairs bonded at 100 °C. However, the shear strength of the pairs bonded at lower temperatures (40 and 60 °C) could be improved by extending the press time from 20 to 120 min. Addition of citric acid (CA) improved the viscosity of the WCSM adhesive at 20% solid content, but lowered the adhesive strength. The addition of denaturing reagent sodium dodecyl sulfate (SDS) showed reverse impacts on the adhesive strength and viscosity, compared to CA addition. Based on these observations, eight adhesive slurries were formulated with 20 and 30% of WCSM, 3% of CA or SDS, or 9.6% or 19.1% of denaturing reagent guanidine hydrochloride (GdmCl), and their bonding strengths were tested. These formulations could be used as the basis for developing low temperature WCSM-based wood adhesives to meet the criteria of both operational flowability and shear strength of the domestic furniture and small utensils niche markets for forest products.     

木材加工用单组分室温湿气固化异氰酸酯树脂的研制

详细研究了NOC/OH 摩尔比、聚氧化乙烯二醇分子量、聚氧化乙烯二醇含量、溶剂种类和树脂固体含量等主要因素对木材加工用单组分室温湿气固化异氰酸酯树脂胶性能的影响,最后优化出固化速度快、胶接效果优良、性能达到结构胶粘剂要求的单组分室温湿气固化异氰酸酯树脂胶粘剂的合成工艺。     

Soy-oil-based waterborne polyurethane improved wet strength of soy protein adhesives on wood

Soy-oil-based waterborne polyurethane (WPU) is used to improve wet strength in shear test of wood bonded with an adhesive of soy protein isolate (SPI) by dispersing WPU into SPI slurry. WPU׳s effects on the physiochemical properties of WPU-SPI adhesives are characterized through Fourier transform infrared spectrum, transmission electron microscopy, thermal analysis, contact angle, and mechanical strength. Wet strength of the WPU-SPI adhesives increases by 65% compared to SPI control. Moreover, the microstructure of WPU has effects on the interactions between WPU and SPI. In this study, smaller and more uniform distributed WPU0002 is easier to interact and form stronger crosslinking network with protein than WPU0500. The stronger interaction between WPU0002 and protein results in increased viscosity and bond strength. The WPU-SPI blended adhesives show significantly improved wet strength, demonstrating their potential as wood adhesives.     

水性高分子-异氰酸酯拼板胶的研制

采用一种高级脂肪酸酯改性酪酸乙烯酯乳液和用交联改性多亚甲基多苯基多异氰酸酯(PAPI)为固化剂,研制了一种胶接强度高、适用期长、耐水性能优良的硬木拼接用双组分水性高分子-异氰酸酯胶粘剂。     

冷等离子体处理对木材胶接性能的影响

为了进一步提高木材的胶接性能,采用冷等离子体处理法对木材表面进行处理,并对处理前后木材表面的化学组成、胶接性能等进行了测定。结果表明:经N2冷等离子体处理后,木材表面的氧/碳原子浓度比增加,产生了大量含氧官能团或过氧化物,同时引入了N元素,推测有-NH2生成;经冷等离子体处理后,木材的最大胶接强度提高了20%左右;胶接强度的增幅与处理气体的类型有关,在其它条件保持不变的情况下,各种气体的表面处理效果依次为氧气氨气氮气氩气。     

金属/丁腈橡胶粘接工艺试验

试验了胶层厚度、烘干工艺对金属/丁腈橡胶(NBR)粘接强度的影响,完成了优化后工艺的适用期试验,以及产品的制造和试验。结果表明,控制胶粘剂HT380的胶层厚度,烘干温度为50℃,烘干时间为30 m in时,可以获得良好的工艺性能和粘接强度,能够满足丁腈橡胶与结构复杂、技术要求高、使用条件苛刻的金属产品的粘接。