异氰酸酯粘合剂及其应用技术

异氰酸酯粘合剂具有优良的化学粘合机理，其性能优于其他刨花板生产用粘合剂。文章从异氰酸酯的性能、机理、应用工艺及防粘工艺等几方面，进行了详尽的论述，为异氰酸酯粘合剂在刨花板生产上的实际应用提供了技术依据。     

绿色环保型刨花板用异氰酸酯粘合剂及其应用技术

异氰酸酯粘合剂由于具有新颖的木材胶合概念及固化后不残留有害物质等优点，逐渐为国内外刨花板生产厂家所看好。国外早在７０年代就有异氰酸酯粘合剂用于刨花板生产的报道，而真正进入工业化生产还是近两年的事；在我国，异氰酸酯粘合剂在刨花板中的应用方面，由于存在产品成本及应用技术等问题，目前仍处于开发探索阶段，本文主要简述一下异氰酸酯粘合剂的粘合机理及相应的应用技术。１异氰酸酯粘合剂性能及粘合机理 异氰酸酯品种较多。经多次试验比较，笔者认为多亚甲基多苯基异氰酸酯粘合剂性能良好。这种异氰酸酯粘合剂在常温下是一种…     

PVAcEm改性溶剂型粘合剂的研制

溶剂型水溶粘合剂是通过对ＰＶＡｃＥｍ改性，即提高ＰＶＡｃＥｍ的粘接力并扩大其应用范围而研制成的新型粘合剂。该粘合剂应用于可降解聚乙烯塑料薄膜育苗容器塑—塑与纸—塑的粘合，效果良好。文中探讨了适宜的改性材料、溶剂及常温下配置工艺条件。     

可降解聚乙烯薄膜育苗容器制作专用胶的研制

研制出一种制作可降解聚乙烯薄膜育苗容器专用的水溶性粘合剂,该粘合剂系常温下配制,无毒无害,具有粘合力强、适时水溶的优点,是目前聚乙烯材料制作育苗容器较为理想的粘合剂。     

啤酒瓶贴标用复合淀粉粘合剂的研制

通过对聚乙烯醇（ Ｐ Ｖ Ａ）缩甲醛工艺的改进，合成一种高固含量、高粘性的 Ｐ Ｖ Ａ缩甲醛粘合剂，该粘合剂与淀粉复合，形成一种啤酒瓶贴标用粘合剂。     

多酚浸出物和聚异氰酸盐交联剂是生产碎料木材产品的粘合剂

粘合剂含有(a)多酚浸出物和(b)聚异氰酸盐交联剂。用途和优点:制成木材产品需要细碎的木碎料和粘合剂结合。由木碎料和粘合剂混合成型的产品,固化混合,特别是要用加热     

新型淀粉粘合剂

目前在我国瓦楞纸板纸箱生产企业遍布各地,仅成都一地,就有各种规模的纸箱生产厂２００多家,业已形成庞大的生产行业,致使生产纸箱所用的粘合剂数量惊人,前景广阔。长期以来,我国瓦楞纸箱生产一贯使用硅酸钠（即“水玻璃”）作粘合剂。由于它容易吸潮、泛碱,用它生产的瓦楞纸箱容易垮塌。另外由于硅酸钠有毒,用它生产的纸箱不能用来包装食品,在国际上早已禁用。近年来包装行业迫切要求一种粘性好、无毒、无味、干燥快、无腐蚀性的优良粘合剂来取代水玻璃、以满足包装行业飞速发展的需要。作为取代水玻璃的淀粉粘合剂,必须满足下列…     

防霉壁纸粘合剂

防霉壁纸粘合剂一般的壁纸粘合剂无防霉效果，故壁纸贴在湿度较大的墙壁室内时易生霉，霉斑先在壁纸与墙壁的粘合处产生，这种黑色霉斑然后逐渐地漫延到壁纸的表面，产生非常难看的黑色斑纹，失去了壁纸贴在墙壁上的装饰效果。本防霉壁纸粘合剂具有防霉性能，使壁纸的正面...     

无甲醛细木工板用粘合剂

细木工板主要有装饰用大芯板和层压板,目前这些板材用粘合剂主要以脲醛树脂为主。即使脲醛树脂的甲醛含量控制在0.5%以下,但在固化过程中的固化反应为可逆反应,仍有甲醛放出,同时粘合剂甲醛含量的降低,导致冷压的时间延长一倍。因此从根本上解决细木工板粘合剂的甲醛释放问     

提高龟药疗效五法

龟类的生命力和抗病力较强，疾病较少，但是在人工饲养条件下，由于饲养场地，温度、饵料等多种因素的影响，有时也会发生各种疾病，浙江省海宁市袁花镇科协特种养殖学会会员蒋建月积累了丰富的养龟技术、疾病防治的经验，现就蒋建月总结的提高龟药疗效的五种方法介绍于下。供读者参考选用。 １、改进粘合剂 粘合剂的粘性要强，如果粘性不强，药物就是易在水中散失；既浪费药物，又耽误龟病的治疗时机。试验表明，使用标准小麦面粉，红薯淀粉、绿豆及蚕豆等淀粉都是较好的粘合剂原料，即把粘合剂与药物粘合在一起，最好制成颗料粒药饵或团状…     

指接材研究现状与进展

概述国内外指接材的研究和发展现状,对指接材发展中存在的产品质量差、指接强度不高、指接接合不严密、材面质量粗糙等问题进行分析,从指接刀具、胶黏剂、指接材性能评估方法等方面提出今后的研究方向.     

Finger-jointing green softwood: Evaluation of the interaction between polyurethane adhesive and wood

Existing European standards for finger-jointing of load-bearing lumber require the wood to be dried before gluing. This article presents a study on the properties of green-glued finger joints, wet wood being bonded prior to drying. Issues to consider, in comparison to finger-jointing of dry wood, are mechanical performance of the joint, absorption of the polymer by the wood in its natural/wet state, and the chemical reactions of the adhesive on contact with water. Finger-jointed samples were tested in bending, and the glue joints analysed by optical microscopy, scanning electron microscopy and microdensitometry. A patented one-component polyurethane adhesive developed for gluing-green wood which has a moisture content usually higher than 70% was used in the study. The resulting green-glued joints showed improved strength properties in comparison to dry-jointed joints. The results confirm that green-glued joints provide a wide, continuous wood/adhesive interface from one substrate to the other. The adhesive penetrates several cells deep and the density of the wood adjacent to the joint surfaces is increased. The results also indicate that the patented adhesive forms covalent bonds to the wood substrate.     

Finger-jointing green softwood: Evaluation of the interaction between polyurethane adhesive and wood

Abstract

Existing European standards for finger-jointing of load-bearing lumber require the wood to be dried before gluing. This article presents a study on the properties of green-glued finger joints, wet wood being bonded prior to drying. Issues to consider, in comparison to finger-jointing of dry wood, are mechanical performance of the joint, absorption of the polymer by the wood in its natural/wet state, and the chemical reactions of the adhesive on contact with water. Finger-jointed samples were tested in bending, and the glue joints analysed by optical microscopy, scanning electron microscopy and microdensitometry. A patented one-component polyurethane adhesive developed for gluing-green wood which has a moisture content usually higher than 70% was used in the study. The resulting green-glued joints showed improved strength properties in comparison to dry-jointed joints. The results confirm that green-glued joints provide a wide, continuous wood/adhesive interface from one substrate to the other. The adhesive penetrates several cells deep and the density of the wood adjacent to the joint surfaces is increased. The results also indicate that the patented adhesive forms covalent bonds to the wood substrate.     

Estimating Strength of Finger-jointed Dimension Lumber by Nondestructive Methods

Structural finger-jointed (FJ) lumber was used mainly in structural applications including glue-laminated beams and wooden I-joists and more recently in parallel chord wood trusses. The paper evaluated strength properties of structural FJ lumber by three nondestructive methods (edge-wise bending, longitudinal and transversal vibration) in order to find an alternative to traditional evaluation methods. Lumber was sawn from the logs following a pattern typically used in China to maximize the volume of recover...     

细木工板生产线的工艺设计特点

本文以生产规模１万ｍ＾３／ａ细木工板生产线为例，阐述了该生产线的工艺设计特点和设备选型。针对不同的锯材质量采用不同刨光工艺。选用指接设备、将指接芯条用在木芯板边部，既提高了细木工板外观质量又可提高木芯板强度，胶拼后的木芯板采用宽度压刨刨平，采用燃气为加热介质的干燥窑，可节省能源４０％，拼板机和热压机采用导热油为加热介质，可节省能耗３０％，砂光机选配脉冲袋式除尘器，除尘效率高。     

Evaluating the strength of finger-jointed lumber of Gmelina arborea in Costa Rica

The use of finger-jointed lumber of Gmelina arborea (gmelina) for the production of glue-laminated beams is becoming more important to the wood industry in Costa Rica. At the request of the local wood industry, two different kinds of adhesives, thermoplastic polyvinyl emulsion (catalyzed PVA) and 1-part polyurethane adhesive (PU) were tested on finger joints of gmelina wood and their strength properties compared under dry, boiled, and saturated conditions. The results showed that under the boiled and saturated conditions, the PVA adhesive exhibited low tensile strength and poor distribution of failures while PU showed much more promise. Based on our preliminary results, the PU adhesive can be successfully used for finger-joint boards of gmelina. Palabras clave: Adhesivos, Melina, Modos de falla, Vigas laminadas Resumen. El uso de la madera unida con juntas de dedo (finger-jointed) para la producción de vigas laminadas-encoladas está tomando mayor importancia en la industria maderera de Costa Rica. Atendiendo la solicitud de la industria, sobre la calidad de los finger joints de la madera de melina, se ensayaron dos tipos diferentes de adhesivos, una emulsión de polivinilo catalizado (thermoplastic polyvinyl emulsion, catalizado, PVA) y un adhesivo de poliuretano (polyurethane adhesive, PU) de un componente, para comparar sus características de resistencia bajo condiciones secas, de ebullición y de saturación. Los resultados muestran que bajo condiciones de ebullición y saturación, el adhesivo PVA tiene una baja resistencia a la tensión y una deficiente distribución de fallas, mientras que el PU mostró resultados mucho más prometedores. Basados en los resultados preliminares, el adhesivo PU puede ser utilizado exitosamente para unir las tablas de melina con juntas de dedo.     

我国目前家具用材及其发展趋势

家具生产原材料已从全实木时代进入了一个多种替材料与之并存的新时代。同时绿色的家居环境也要求生产“绿色家具”，随着人造板工业的发展，中密度纤维板、刨花板、集成材、人造薄木等材料将成为家具制造的主要原材料。     

高温热处理木材胶合性能的研究

笔者研究了桦木、落叶松和樟子松高温热处理材的胶合性能,并与常规干燥材进行了对比。测试结果表明木材的胶合剪切强度与所用的胶黏剂有关,聚氨酯胶合的三个树种木材的剪切强度普遍大于白乳胶胶合的木材。无论是室内用的白乳胶或室外木结构用的聚氨酯胶都能与三个树种的高温热处理材很好地胶合,胶合试件的浸渍剥离率或煮沸剥离率皆为零。木材经高温热处理后,其剪切强度均有不同程度的降低,阔叶材桦木下降幅度最大,针叶材落叶松下降幅度最小。     

间伐小径木指接技术研究

间伐材指接胶合加工，变短材为长材，弯材为直材，为合理，有效利用间伐材开辟了新路。对间伐材木材含水率，指接端压的大小和时间，指接后养护时间，涂胶量，指榫规格等对指接材抗弯强度的影响进行了研究，并测定了苯酚，间苯二酚，甲醛树脂胶胶合的指接材快速老化性能。     

杉木生材含水率分布及其对气干的影响

以人工林杉木为研究对象,研究生材状态下不同厚度锯材含水率的差异,比较含髓心、钝棱与其他类型等3类锯材的含水率差异,建立生长轮宽度与锯材含水率的关系,分析生材状态含水率对锯材气干周期的影响。研究结果显示,25mm和40 mm的锯材含水率差异极显著;含髓心锯材含水率最低,其次是其他类的,最大是含钝棱锯材;随着生长轮宽度减少,锯材含水率增大;生长轮宽度为4 mm时,是生材含水率分界线,即当生长轮平均宽度小于和不小于4.0 mm时,锯材含水率差异极显著;25 mm和40 mm厚不同含水率锯材各2组气干至含水率25%,低含水率锯材较高含水率的气干周期分别缩短57%和66%。