一种常温应变计用环氧-酚醛基底胶的研制

以E-12环氧树脂、酚醛树脂、聚乙烯醇缩甲醛和双氰胺为原料制成了一种常温应变计用基底胶。通过对K值分散、蠕变和机械滞后等指标的测试研究了原料用量、基底胶合成温度等对应变计工作特性的影响,确定了基底胶的最佳配方及工艺:E-12环氧树脂40份;酚醛树脂20份;聚乙烯醇缩甲醛1份;双氰胺2份,合成温度130℃。结果表明,该基底胶平均剥离强度为2.7 N/cm,5℃下储存期为3个月,用该基底胶制成的应变计的工作特性满足国标要求。     

用改性环氧胶黏剂粘接硫化丁腈橡胶

以端异氰酸基聚氨酯预聚体改性环氧树脂和双氰胺为主要原料制备了一种单组分耐热环氧树脂胶黏剂,该胶可以对表面未处理的丁腈橡胶进行粘接。文中考察了增韧剂种类、增韧剂用量对粘接强度的影响,同时考察了促进剂种类和用量对凝胶时间和贮存期的影响。实验结果表明,该胶黏剂对丁腈橡胶的粘接强度好,具有较好耐热性和较长贮存期。     

粘贴工艺对碳纤维布增强聚丙烯板材抗冲击性能的影响

利用碳纤维布外贴的方式增强聚丙烯板材的抗冲击性能,为制备出性良好且碳纤维布不易脱粘的复合板材,设计出了环氧树脂粘贴工艺、环氧树脂粘贴打孔工艺、PP胶粘贴工艺和混合粘贴工艺,并对不同制备工艺下的复合板材分别进行了4、8、12 J的落锤试验.结果表明:在不同冲击能量下,混合粘贴工艺的方式对聚丙烯板材的荷载的提高效率最高,同...     

贴片胶的选择与使用

贴片胶在SMT混装生产中具有至关重要的作用。贴片胶通常由基本树脂、固化剂、促进剂、增韧剂以及无机填料等组成，其主要功能是保证元器件位置的正确性。目前在组装、焊接过程中用于保持元器件位置及方向的贴片胶，普遍采用的基本树脂有丙烯酸树脂和环氧树脂两种，它们具有各自的优缺点，如表1所示。由于环氧树脂有很好的电气性能，且粘接强度高，故目前使用环氧树脂贴片胶的居多数。     

石油发酵尼龙改性环氧胶粘剂的研究

石油发酵尼龙改性环氧胶粘剂是一种胶接强度高和抗冲击性能、耐湿热性能好的胶粘剂。本文研究了该胶粘剂的最佳配方和胶接工艺,测试了其耐湿热性能,讨论了各组份用量(尼龙、环氧树脂、双氰双胺固化剂)、尼龙与环氧树脂配比以及固化条件对该胶粘剂胶接强度的影响.     

环氧树脂改性丁腈橡胶的研究

通过环氧树脂和丁腈橡胶的共混,制备出了环氧树脂改性丁腈橡胶硫化胶;考察了环氧树脂种类、用量以及反应性丁腈橡胶作增容剂对共混胶性能的影响.结果表明:使用环氧树脂E12可使丁腈橡胶的拉伸强度和撕裂强度明显提高;在此体系中加入端胺基液体丁腈橡胶后,撕裂强度和硬度进一步提高.硫化胶溶胀试验和红外分析结果表明:端胺基液体丁腈橡胶与环氧树脂发生了部分交联反应.     

一种单组份环保型环氧树脂胶黏剂的制备

本实验以双酚A型环氧树脂为基体树脂,双氰胺为固化剂,咪唑为固化促进剂,BN(氮化硼)和A1₂O₃为填料,再添加适量的其他助剂,制备单组份环保型环氧树脂胶黏剂。通过对粘接强度,热性能、储能模量、玻璃化转变温度的测试,研究了基体树脂、填料、固化剂用量等因素对环氧树脂胶黏剂性能的影响,制备了单组份环保型环氧树脂胶黏剂。     

透水路面用聚氨酯胶的制备研究

以甲苯二异氰酸酯(TDI)、多亚甲基多苯基多异氰酸酯(PAPI)、聚醚多元醇和蓖麻油为主要原料制备含-NCO端基的单组分聚氨酯胶粘剂,与碎石混合制备透水路面。研究了单组分聚氨酯胶粘剂的制备工艺及其用量对聚氨酯碎石透水路面性能的影响。研究结果表明:聚氨酯胶的制备工艺参数:反应温度为75～80℃,反应时间2. 0～2. 5 h,-NCO%含量控制在8%～9%为宜。当聚氨酯胶的用量为5%时,采用3～5 mm的花岗岩碎石制得的透水试样抗压与抗折强度均较高,透水透气性能良好。     

ZG-2汽车折边胶的研制与应用

研究了端羧基丁腈橡胶对环氧树脂的增韧性改原理，经配方设计和制备工艺的完善，开发出粘接强度高、韧性好、工艺性好的ZG－2折边胶，产品综合性能达到国外同类胶种的水平，满足了现生产的使用要求。     

专利介绍

<正>表面贴装技术用贴片胶CN102 850 948(2013-01-02)。该贴片胶以低黏度液体环氧树脂、潜伏性固化剂、固化促进剂、触变剂、无机填料和颜料为原料,在真空状态下搅拌均匀即可。该贴片胶具有耐高温性优、固化速率快、储存稳定性好、湿强度高、触变性佳、不拉丝和不坍塌等优点,可广泛应用于SMT工艺中。     

基于十字交叉法的陶瓷胶粘剂剪切蠕变性能研究

本研究设计了“十字交叉法”陶瓷胶粘剂剪切蠕变试验装置,选取刚性环氧树脂及柔性硅酮结构胶进行剪切蠕变试验,研究了环境温度、剪切应力、粘结面积等因素对胶粘剂剪切蠕变的影响,通过模型拟合对胶粘剂的剪切蠕变行为进行了分析和预测,探究了两种胶粘剂的蠕变破坏模式。结果表明:采用十字交叉法能够准确便捷地测试陶瓷胶粘剂的蠕变性能。增大胶粘层柔性、提高环境温度、增大剪切应力都会加速蠕变的发展,但粘结面积对蠕变速率无明显影响。刚性环氧树脂胶粘剂试样的蠕变失效形式为粘结层内聚破坏及界面脱粘,符合时间硬化模型;柔性硅酮结构胶试样失效形式为粘结层内聚破坏,符合Burgers模型。     

Numerical study of the effect of carbon fiber/epoxy resin adhesive thickness on the creep behaviour of carbon steel plate joints

Nowadays, the use of adhesive and adhesively bonded joints have been considerably appreciated in the industry due to the dramatic reduction in bonding strength, reduced stress concentration, rust prevention, uniform bonding of the bonding surface and a significant reduction in costs compared to other types of permanent joints such as welding. In this study, the effect of adhesive thickness on creep behaviour of a single lap adhesive joint with the aid of Abaqus FEM software is investigated. It should be noted that the two-layer and two-dimensional models are considered, in which their adhesive layer is made of a reinforced epoxy resin with 0.5% carbon fiber and the adherend layers are made of carbon steel plates, which is affected by tensile forces. Since the main purpose of this paper is to study the effect of adhesive thickness on the adhesive joints behaviour, the effects of the distribution of shear stress, effective stress and creep strain were studied in different thicknesses of the adhesive layer. The results show that by increasing the thickness, the stress and the creep strain decrease, and over time, the stress decreases and the creep behaviour of adhesives increases.     

Creep behaviour of steel bonded joints under hygrothermal conditions

The aim of this research is to study the influence of moisture absorption at low moisture contents on the creep behaviour of an epoxy adhesive in steel bonded joints. Single lap joints were manufactured using high strength steel adherends and a two-component epoxy adhesive. The single lap joints were tested at load levels corresponding to average lap shear stresses of ± 5%, 15%, 30% and 45% of the dry lap shear strength in both 40 °C air and 40 °C distilled water. Specimens were not pre-aged to be able to analyse the coupled effect of moisture and loading. The test results show that an increase in the load level resulted in an increase in the instantaneous strain and in the creep strain rate. The creep strain of single lap joints loaded in water was generally larger than for the ones loaded in air. For joints loaded in water the creep behaviour was found to be dependent on the moisture concentration in the adhesive. At low moisture percentages creep was suppressed, resulting in a lower instantaneous strain. At higher moisture percentages creep was promoted, resulting in a larger strain rate. The suppression of creep at low moisture percentages is attributed to water molecules bonding to the epoxy macromolecules, resulting in a reduction in molecular mobility and a smaller creep strain. At higher moisture percentages the plasticizing effect of the water dominates, resulting in a larger creep strain. The Maxwell three-element solid model and Kelvin-Voigt three-element solid model were used to simulate the creep behaviour of the single lap joints loaded in air and water. The models gave good representations of the creep response across the different load levels in both water and air, they were however unable to give a correct representation of the instantaneous strain of the single lap joints loaded in water. This is attributed to the models being unable to account for the present short-term relaxation process that is dependent on the moisture concentration.     

单组分常温固化EP胶粘剂的研制

以环氧树脂(EP)为基体树脂、有机硅为偶联剂,成功研制出一种常温固化的建筑用EP/有机硅单组分胶粘剂,并对其力学性能、耐老化性能、耐盐雾性能和耐介质性能等进行了测定。结果表明:该胶粘剂固化前呈黏稠状液体,可常温固化,施工性能较好;其拉伸强度超过15MPa,剪切强度超过10MPa,并具有较好的耐介质性能;该胶粘剂避免了传统EP胶粘剂在施工方面的诸多不足之处,具有良好的应用前景。     

羟基磷灰石增强环氧树脂结构胶的力学性能研究

采用羟基磷灰石(HA)对环氧树脂结构胶进行改性。对改性后结构胶的力学性能进行测试。实验表明:随着HA的掺量增加,环氧结构胶的压缩强度、冲击强度、粘钢剪切强度提高、拉伸强度略有降低;当羟基磷灰石的掺量为5％时。环氧树脂结构胶的压缩强度、冲击强度分别为92MPa、6．8kJ／m2,比纯环氧树脂基体提高28％和70％;当羟基磷灰石的掺量为7％时,环氧树脂结构胶的粘钢剪切强度为26．4MPa．比纯环氧树脂基体提高55％,羟基磷灰石对环氧树脂有较好的增强增韧作用。     

端环氧基液体丁腈橡胶改性环氧树脂结构胶的研究

采用ETBN(端环氧基液体丁腈橡胶)增韧EP(环氧树脂),制备了单组分EP结构胶。利用红外光谱(FT-IR)、扫描电镜(SEM)等手段对结构胶的拉伸剪切强度及微观结构进行了表征。结果表明:制备该结构胶的适宜条件为m(EP):m(ETBN)=20:3,80℃均匀搅拌20 min,130℃固化1 h;由该结构胶制成的钢-钢胶接件,其室温拉伸剪切强度为23.66 MPa,并且其耐介质性能良好,说明ETBN对EP的增韧效果较好。     

硅改性BPA-PA酚醛环氧树脂导电胶的合成及性能

以双酚A多聚甲醛酚醛树脂（BPA-PA酚醛树脂）、二甲基二甲氧基硅烷和环氧氯丙烷为原料,通过酯交换反应和亲核取代反应得到硅改性BPA-PA酚醛环氧树脂。采用傅里叶变换红外光谱（FTIR）、X射线光电子能谱（XPS）分析进行结构确证。结合非等温DSC、T-β外推直线和FTIR分析研究了最佳固化工艺条件。探讨了不同硅烷添加量对硅改性BPA-PA酚醛环氧树脂性能的影响。最后以硅改性BPA-PA酚醛环氧树脂为基体树脂,加以导电填料和助剂,制备出中温型导电胶。对导电胶进行拉伸剪切强度、体积电阻率和热重测试分析,结果显示：自制硅改性BPA-PA酚醛环氧树脂导电胶拉伸剪切强度达到20.18MPa、体积电阻率达到7.44×10^-4Ω·cm,残炭量达到68.89%。相对市售E-51环氧树脂所制导电胶,自制硅改性BPA-PA酚醛环氧树脂导电胶拉伸剪切强度提高5.73MPa,体积电阻率降低3.86×10^-4Ω·cm,残炭量提高7.49%。     

室温固化耐热环氧胶粘剂的制备与性能研究

采用氨基硅油和液体端羧基丁腈橡胶(CTBN)对环氧树脂进行化学改性,制备出室温固化耐热环氧胶粘剂。探讨了氨基硅油和CTBN的加入量、环氧树脂种类等对胶粘剂粘接性能的影响。实验结果表明:用氨基硅油和CTBN共同改性环氧树脂制得的胶粘剂性能与末改性树脂相比有显著的提高;酚醛环氧树脂F-44和环氧树脂E-51进行复配时,所得胶粘剂的粘接性能较佳。     

电机用单组分环氧树脂胶粘剂的研制

通过剪切强度和剥离强度测试研究了不同环氧树脂配比,不同增韧剂及促进剂对单组分电机胶性能的影响。结果表明,CYD-128环氧与双酚F环氧质量比为80∶20,纳米丁腈橡胶粒子VP-501为增韧剂,双氰胺作固化剂,咪唑为促进剂制得的单组分环氧胶25℃和150℃的剪切强度分别达到15.9 MPa,7.3 MPa,可用于电机的低碳钢与磁体的粘接。