通用型双组份环氧胶粘剂的制备与性能研究

以环氧树脂E-51和E-44复配作为胶粘剂的基料,制备了一种固化速度快、耐温且力学性能好的环氧胶。本文主要研究了不同配比的环氧树脂对环氧胶性能的影响、以及不同固化剂对环氧胶耐热性能的影响。结果表明,当E-51和E-44二者采取1∶1的质量比时,其拉剪强度最高;选择R-2026作为本实验环氧胶体系中的固化剂,胶粘构件的强度最好;使用JH-5140LA固化剂制备的胶粘剂其自身热稳定性最优。     

带有压敏性的环氧胶带的研制

研制带有压敏性的环氧胶带,可以使用表面涂或内部加压敏胶的方法,两种方法有各自的优缺点。表面涂压敏胶,压敏性好,但固化的粘接强度较低;内加压敏胶则相反。全面衡量,内加压敏胶的方法较好。     

J－91耐热性环氧化酚醛胶粘剂的研制

本文论述Ｊ－９１胶的性能以及环氧酚醛树脂、高活性环氧树脂、固化剂的影响．认为高活性环氧树脂对降低Ｊ－９１胶的固化温度，提高胶的耐热性是非常重要的．     

室温固化环氧胶粘剂的研究现状与发展趋势

本文综述了双组分室温固化环氧树脂胶粘剂的发展过程与研究现状，介绍了近年来国内外几种性能优异的室温固化环氧胶粘剂，指出双组分室温固化型环氧胶的发展趋势是耐高温、高强度、高耐久性及快速固化。     

新型低温固化双马来酰亚胺树脂基体研究

双马来酸亚胶树脂基体耐热性好，具有优异的使用性能；但固化温度往往高于２００℃。引发剂可有效地降低固化温度，但所得树脂基体脆性很大。本文在二元胺扩链、烯丙基双酚Ａ共聚后的双马来酰亚胺树脂锄中加入引发剂，制得一种软化点低、韧性适中、耐热性好、贮存稳定的低温固化双马来酰亚胺树脂ＢＤＤＤ体系。为今后该树脂在复合材料构件上的应用奠定了良好的基础。     

室温固化厚胶层高强度环氧胶粘剂

采用环氧树脂予先与端羧基液体丁腈橡胶接枝以及合成子主链上带有多个醚键的二胺作固化剂，使调制的双组份糊状室温固化型环氧胶粘剂的甲、乙两组份均具有内增韬机制的双组份糊状室温固化型环氧胶粘剂的甲使得到的室温固化环氧胶具有极高剪切和剥离强度，并展现了厚胶层条件下仍具有高强度的特点。     

新型弹性环氧胶粘剂在湖南问世

新一代弹性环氧胶粘剂前不久由湖南省高新技术企业———长沙蓝星化工新材料有限公司开发成功,该产品也　被认定为湖南省高新技术产品。他们生产的新型弹性环氧胶粘剂共包括:新型弹性环氧胶粘剂、室温固化柔韧性环氧胶粘剂、滴塑水晶硬质胶　粘剂、滴塑水晶软质胶粘剂(BS - 2 10 1A/B)主要特点是粘度低、操作性能好,配胶简单,使用方便;放热低,使用期长;　固化后胶层柔软性极高,伸缩率大,耐冲击性能优良,胶合件应力小;对水、二氧化碳不敏感,没有胺浑浊现象,固化　物表面光泽好;固化剂配合比例大,称量误差带来的影响小;低毒低刺激性,对操作…     

高性能环氧浇注胶固化工艺及性能研究

对环氧树脂体系进行了固化动力学研究,确定了三段法的固化工艺。研究了体系中填料含量对环氧浇注胶性能的影响,并得到了导热性能、机械性能以及电气性能优良的新型环氧浇注胶,其弯曲强度和拉伸强度分别达到114MPa和65MPa。     

WD3102室温固化耐高温胶粘剂的研制

通过对环氧树脂、液体橡胶、固化剂的选择,研制了一种可以室温固化、耐高温性能好的双组份环氧胶粘剂。     

室温固化耐热环氧胶黏剂的耐介质性能

对自制间甲酚-多聚甲醛改性多元胺/E-44室温固化耐热环氧胶黏剂进行了耐腐蚀性能及其腐蚀后的耐热性能研究,其固化物具有优良的耐常用酸、碱和有机溶剂腐蚀性;其粘接件具有优良的耐常用酸、碱和有机溶剂的腐蚀性能及其腐蚀后150~200℃的耐热性能。     

New Developments in Structural Adhesives for the Automotive Industry

Recently developed epoxy paste adhesives, reactive hot melts, adhesive film tape and polyurethane adhesives are presented for structural bonding in the automotive industry. Paste adhesives usually require a precure stage to obtain handling strength of the joints and to guarantee wash-out resistance of the adhesive in the paint baths. This step can be omitted with reactive hot melts and adhesive film tape, which are solid before and after their application. In addition they allow an improved working hygiene. Some mechanical properties of the adhesives are shown such as lap shear strength and peel strength as well as lap shear strength as a function of the bondline thickness. Results of the excellent durability of epoxy one-component pastes, reactive hot melts and adhesive film tape are given from cyclic environmental and salt spray tests.     

Development of a practical visual indicator tape for adhesive and coating analysis

A ninhydrin-coated, pressure-sensitive adhesive tape has been developed for the purpose of detecting specific chemical substances in various materials. Ninhydrin undergoes a visible color change in the presence of amines, isocyanates, and other chemical compounds. The tape was prepared by dissolving ninhydrin and applying it to an adhesive tape with an airbrush. The tape was allowed to dry and then applied to the surface of various cured and uncured materials to test for reactivity. It was then used successfully to detect unreacted components present in uncured or partially cured epoxy adhesives and coatings.     

The effects of partial bonding in load carrying capacity of single lap joints

The effects of the presence and size of gaps in the band single lap joint geometry were studied. Two types of adhesives: a deformable, acrylic tape and epoxy putty were used as model adhesives. When using the epoxy putty, the substrate overlap end conditions were also varied by machining 10° end tapers in some joints. For both adhesive types, the introduction of the gap had a moderate negative effect on the load carrying characteristics of the joint, but joints utilizing the epoxy putty maintained joint strength as the gap size was increased to 9.53 mm (38% gap), while the highly deformable acrylic tape case displayed a constant decline and maintaining constant ultimate shear stress values. We suspect that this variation is due to a combination of the different failure modes of each adhesive and their differing moduli, as well as how these relate to the peeling stresses at the ends of the bond length. In the epoxy putty series, the samples with tapered substrates consistently carried higher loads than those with unmodified substrates. This improvement is a manifestation of the ability of the tapered joint geometry to reduce peeling stresses experienced within the adhesive layer.     

微胶囊促进剂在环氧树脂胶带固化中的应用

把环氧树脂固化促进剂制成了以脲醛树脂为外壁的微胶囊 ,并将其应用于环氧树脂胶带中 ,结果表明 ,微胶囊促进剂的使用可以显著提高胶带的使用期 ,尤其是使用部分反应的EMI微胶囊 ,且微胶囊的加入对胶带的粘结强度和耐热性基本没有不利影响     

The effect of water on the adhesion of organic coatings on aluminium

Water normally decreases the strength of adhesive joints. In the case of epoxy coatings on aluminium, however, after an initial decrease the adhesive strength increased with the time of exposure to water. It is suggested that this increase is caused by the hydration of aluminium oxide adjacent to the adhesive joint, thus enabling additional hydrogen bonding between the organic coating and its support.

Results obtained by measuring adhesion with peel and tape tests on aluminium foil and an alloy with different surface pretreatments and different curing conditions have been compared. It is shown that the tape test is useful for the semi-quantitative determination of the stability towards water of an adhesive joint.     

Mechanical properties of cryogenic epoxy adhesives: Effects of mixed curing agent content

Phenyl glycidyl ether was used to react with solid metaphenylene diamine (MPDA) to produce N-(3-phenoxy-2-hydroxypropyl)-1,3-benzenediamine (NPHB). MPDA was intentionally formulated to have an excessive amount to obtain a new liquid MPDA–NPHB mixture. The mixed curing agent was indicated to have a few advantages over MPDA. The mixed curing agent was then used to cure diglycidyl ether of bisphenol A as cryogenic epoxy adhesive. The effects of the MPDA–NPHB content were systematically studied on the impact strength and shear strength at both room temperature and cryogenic nitrogen temperature of the epoxy adhesive. Moreover, two coupling agents with various contents were used to further enhance the shear strength of the optimal cryogenic epoxy adhesive. Finally, differential scanning calorimetry analysis showed that the modified adhesive showed a higher glass transition temperature than the unmodified adhesive.     

环氧端基酚酞聚芳醚腈改性环氧树脂胶粘剂性能的研究

通过差示扫描量热 (DSC)、热解重量分析 (TGA)和粘接强度的测定 ,对环氧端基酚酞聚芳醚腈改性的环氧树脂胶粘剂的性能进行了研究     

Experiments on the combined use of a double-sided pressure-sensitive tape and an epoxy adhesive to reduce handling time

In many industrial assemblies with structural adhesives, the handling time, i.e. the time to safely move adhesively bonded parts, may slow down manufacturing process and result into additional costs. For that reason, in some cases, the traditional mechanical connections (rivets, bolts, welds) are still preferable when the structure must be completed in a short time. In this work a new type of hybrid joint, characterized by the combined use of an epoxy adhesive and a double-sided pressure-sensitive tape, is proposed and characterized by experimental tests on single-lap joints with a large overlap. The results showed that these hybrid joints allow for reducing the handling time of the joint, preserving approximately the same strength. The proposed solution exploits the non-uniform stress distribution in the bondline of a single-lap joint, resulting in a low stress area at the centre of the overlap. The presence of an adhesive tape in this region produced either a negligible or minor drop (~20%) in strength depending on the epoxy used, while provided the joint with sufficient strength for being handled before the full cure of the epoxy.     

Progressive Failure Analysis of Reinforced-Adhesively Single-Lap Joint

The failure behavior of reinforced-adhesively single-lap joints was investigated experimentally and numerically. The reinforced adhesive was produced by mixing waste composite particles and an epoxy-based commercial adhesive. The single-lap joint was prepared with an adhesive and unidirectional fiber glass/epoxy composite plates with a (0°/90°)₃ stacking sequence. Three types of adhesive were used: an un-reinforced adhesive (ADH), an adhesive mixed with glass fiber-reinforced epoxy resin composite plate particles (GFRC), and an adhesive mixed with carbon fiber-reinforced epoxy resin composite plate particles (CFRC). The adhesive thickness (ta) and overlap length (lap) were 0.4, 0.8, 1.2, and 1.6 mm and 10, 20, 30, and 40 mm, respectively. Progressive failure analysis was performed with the ANSYS? 11.0 finite element program using ANSYS? parametric design language (APDL) code. In the numerical study, the failure loads of the composite and the adhesive were determined with the Hashin failure criteria and the Tresca failure criteria, respectively. The difference between the experimental and numerical studies ranged from 2% to 10%. The failure load of reinforced-adhesively single-lap joints was 1.3–22.8% higher than that of the un-reinforced adhesive.