结构胶粘剂的发展和应用

概述了结构胶粘剂的产生和发展史,介绍了结构胶粘剂的分类及在航空、航天领域的应用概况.以J-系列环氧树脂基耐高温结构胶粘剂为例介绍了结构胶粘剂的种类、主要技术性能和要求,展望了耐高温结构胶粘剂今后的发展趋势.     

绿色纸塑胶粘剂研究

介绍了绿色纸塑胶粘剂的种类,综述了水基丙烯酸系胶粘剂、聚醋酸乙烯水性胶粘剂、水基及无溶剂聚氨酯胶粘剂和热熔胶的研究,指出了绿色纸塑包装胶的发展趋势.     

新型室温固化双组分胶粘剂的研究

利用自合成聚丙烯酸酯聚合物和环氧丙烯酸酯制备了新型双组分室温固化丙烯酸酯胶粘剂.研究并讨论了该胶粘剂组成的比例、活性单体对粘合强度、胶粘性能和胶粘剂的贮存稳定性的影响、确定了室温固化氧化-还原体系剂及适宜固化时间用量.该胶粘剂对金属的拉伸强度可达23.5MPa.     

导电胶粘剂的研究进展

导电胶粘剂的发展对电子技术的发展有着极其重要的意义.介绍了导电胶粘剂的分类、组成、导电机理和研究现状,并指出了导电胶粘剂在实际应用中需要解决的问题.     

高光膜胶粘剂的研制

高光膜由PVC、胶粘剂、PET膜复合而成.根据其特点研制的环氧树脂胶粘剂与传统的胶粘剂相比,不需要对粘贴面PET膜进行特殊的表面处理,使用十分方便.     

淀粉胶粘剂的改性研究

淀粉胶粘剂应用历史久远,由于纯淀粉胶粘剂具有粘接强度低、耐湿性差和干燥速率慢等缺点,作为天然高分子的淀粉的改性成为近年来的研究热点.本文从氧化、醚化、酯化、交联和接枝共聚等方面综述了近年来淀粉胶粘剂的研究现状,对淀粉胶粘剂的未来发展提出了看法.     

天然胶乳压敏胶粘剂的研究进展

本文评述了天然胶乳压敏胶粘剂的研究进展,对天然胶乳压敏胶粘剂基体改性、增粘树脂乳化方法以及各组分的拼合进行了综述.并提出了天然胶乳压敏胶粘剂产品的发展趋势.     

星用胶粘剂的辐射效应研究

对星用胶粘剂的辐射效应进行了研究.在星上使用的胶粘剂必须满足空间环境条件下的需要.针对几种用于空间的胶粘剂,测试了力学性能随辐射剂量的变化.对试验进行了讨论,总结了胶粘剂力学性能随辐射剂量的变化规律.     

聚酰亚胺胶粘剂的现状与研究进展

聚酰亚胺胶粘剂是一种重要的结构胶粘剂,本文综述了近年来聚酰亚胺胶粘剂的研究进展.     

胶粘剂在粘接接头内热分解动力学的计算

为了研究粘接接头内胶粘剂的耐热性能,采用X射线能谱分析确定了不同条件下粘接接头内胶粘剂的元素组成及其变化行为,利用X射线能谱计算了胶粘剂的热失重率,进而计算出聚酰亚胺薄膜粘接接头内胶粘剂的热分解动力学,并与空气环境下胶粘剂热分解活化能进行了比较.计算结果表明,粘接接头内胶粘剂的热分解速率低于空气环境下胶粘剂热分解速率,这种分析测试方法为原位表征粘接接头内胶粘剂耐热性能提供了一种新的分析方法.     

A novel method to regulate the density of BaTiO3 ceramics for positive temperature coefficient resistance via tape casting

BaTiO₃ ceramics for positive temperature coefficient resistance (PTCR) were fabricated via tape casting technique and reduction/reoxidation process. A novel method was used to regulate the density of the ceramics via changing binder amount in tape casting green bodies. The influences of different amounts of the binder on density, electrical properties, and microstructure of ceramics were investigated. The BaTiO₃ ceramic monolith without internal electrodes with an addition of binder of 0.84 wt% was sintered in reducing atmosphere at 1150 °C and reoxidized at 800 °C for 1 h showed a resistivity of 56 Ω·cm and a PTCR jump about 3.2 orders of magnitude. The green and sintered density of the samples decreased with the increasing binder amount. The room temperature resistivity increased monotonically with the binder amount. However, the correlation of the PTCR jump with binder amount showed a contrary tendency. These electrical properties can be explained by the Jonker model. The influences of sintering temperature on the density of BaTiO₃ ceramics with different binder amount were also discussed. In addition to the ceramic monoliths without internal electrodes, multilayer elements with internal electrodes were also prepared.     

Quantitative fractography of WC-Co cermets by Auger spectroscopy

A general procedure has been developed to determine the area fraction occupied by the binder on the fracture surfaces of cemented carbides. The area fraction of binder on the fracture surface was obtained from the relative peak-to-peak height ratios of elements in the binder and the carbide content was measured by Auger spectroscopy on the fracture surface and an adjacent polished section and the volume fraction of binder present in the cermet. This procedure was employed to determine the area fraction of binder on the fracture surfaces of WC-Co cermets with different binder contents and carbide grain sizes. The average binder mean free path and the area fraction of binder together yield the amount of plastically deformed binder per unit area of fracture surface. The volume of deformed binder and its in situ yield strength were combined to obtain a term proportional to the amount of plastic work done per unit area of fracture surface. It is shown that the correlation between this plastic work term and the fracture toughness of the cermets is good, while correlation with binder mean free path alone is poor.     

Evaluation of Xylitab 200, a New Filler/ Binder for Direct Compression, Using Factorial Design

The influence of a number of tablet factors were used to evaluate Xylitab 200®, a new filler/binder for direct compression, following a factorial design. The factors include types of filler/binder, drug, disintegrant, and amount of compression force. In the extended design, two storage conditions were selected. Factors found to have strong influence on tablet qualities from time after manufacturing to storage were drug solubility, amount of compression force, and storage condition. Comparison between tablets manufactured with the new filler/binder and those prepared with a known good filler/binder have shown that the latter is better than the former.     

溶胶凝胶法制备有机无机复合胶粘剂

以羧甲基纤维素钠(NaCMC)、硝酸铝和氨水为原料,通过-COO-基团和Al3+之间的配位键交联实现有机物与无机物的复合,并将所制备的胶粘剂用于复合活性炭的粘结成型。研究表明硝酸铝的用量直接影响所合成胶粘剂的状态和耐水性,粘结成型得到的复合活性炭仍保持较高的比表面积。论文借助对比验证实验对胶粘剂的形成机理进行了初步探讨。     

Further observation of content uniformity of d-alpha-tocopheryl acetate as an oily drug in granules obtained by wet granulation with a high-shear mixer.

Using d-alpha-tocopheryl acetate (VE) as a model drug, we investigated the effects of the amount of binder solution on content uniformity of oily drugs in granules obtained by, wet granulation with a high-shear mixer. When the amount of binder solution was below the water volume for the plastic limit, the content of VE was less than 50% in the fractionated fine granules, but was more than 200% in the fractionated large granules. Large variations were seen in the contents of VE even if the granulation time was extended up to 30 min. This large variation was not decreased by the milling process. On the other hand, when the amount of binder solution was at or above the water volume for the plastic limit, less variation was observed in the content of VE throughout the granules, and the content of VE was fairly uniform. Nuclei rich in VE were formed when VE was adsorbed with the powder before granulation. When the amount of binder solution was below the water volume for the plastic limit, the shearing force of mixer blades to the granules was low, so that the nuclei rich in VE were not fragmented. This led to the nonuniformity of VE content throughout the granules. On the other hand, when amount of binder solution was at or above the water volume for the plastic limit, the shearing force of mixer blades against the granules increased and became sufficient to fragment the nuclei. This led to the uniformity of VE content throughout the granules. This study showed that content uniformity of VE in the granules can be achieved by controlling the physical shearing force of mixer blades by regulating the amount of binder solution.     

纳米Y-TZP凝胶注模成型的研究

对纳米Y－TZP的浆料进行了凝胶注模成型．有机单体丙烯酸胺和交联剂N,N-亚甲基双丙烯酸胺的加入,不但起到使浆料凝胶的作用,还可以大大降低浆料粘度,改善浆料的流变性．有机单体、交联剂、引发剂均有其合适的用量范围．与干压法、等静压法相比,用凝胶注模法成型的素坯密度高、显微结构均匀、烧结体的断裂韧性也较等静压法高．     

Further Observation of Content Uniformity of d-α-Tocopheryl Acetate as an Oily Drug in Granules Obtained by Wet Granulation with a High-Shear Mixer

Using d-α-tocopheryl acetate (VE) as a model drug, we investigated the effects of the amount of binder solution on content uniformity of oily drugs in granules obtained by wet granulation with a high-shear mixer. When the amount of binder solution was below the water volume for the plastic limit, the content of VE was less than 50% in the fractionated fine granules, but was more than 200% in the fractionated large granules. Large variations were seen in the contents of VE even if the granulation time was extended up to 30 min. This large variation was not decreased by the milling process. On the other hand, when the amount of binder solution was at or above the water volume for the plastic limit, less variation was observed in the content of VE throughout the granules, and the content of VE was fairly uniform. Nuclei rich in VE were formed when VE was adsorbed with the powder before granulation. When the amount of binder solution was below the water volume for the plastic limit, the shearing force of mixer blades to the granules was low, so that the nuclei rich in VE were not fragmented. This led to the nonuniformity of VE content throughout the granules. On the other hand, when amount of binder solution was at or above the water volume for the plastic limit, the shearing force of mixer blades against the granules increased and became sufficient to fragment the nuclei. This led to the uniformity of VE content throughout the granules. This study showed that content uniformity of VE in the granules can be achieved by controlling the physical shearing force of mixer blades by regulating the amount of binder solution.     

Investigating the effect of filler types on thermodynamic parameters and their relationship with moisture sensitivity of asphalt mixes

Filler plays a significant role in mastic cohesion and adhesion between aggregate–asphalt binder in asphalt mixes. In the majority of research on investigating moisture damage based on thermodynamic concepts, little attention has been given to the role of filler. In the present study, 20 different combinations of asphalt mixes made with 4 filler types (stone powder, hydrated lime, calcium carbonate and portland cement), with two types of asphalt binder (60–70 and 85–100), and two types of aggregate (limestone and granite) were used. Then thermodynamic parameters (with and without considering the effect of filler) were calculated and the relationship between these parameters and test results of moisture sensitivity of asphalt mixes was investigated using statistical analyses. Results obtained by thermodynamic parameters show that only stone powder filler caused an increase in free energy of adhesion between base asphalt binder and aggregates, and other fillers reduced free energy of adhesion. The maximum amount of debonding energy in samples made by asphalt binder 60–70, was related to mastics containing calcium carbonate and hydrated lime fillers, and in asphalt binder 85–100, mastics containing portland cement and calcium carbonate had the maximum amount of debonding energy. However, the minimum amount of debonding energy was related to the mastic containing stone powder. In addition, the results of moisture sensitivity mechanical tests show that samples containing calcium carbonate and hydrated lime fillers had the maximum amount of tensile strength ratio. Finally, the amount of adjusted coefficient of correlation between debonding energy and modified Lottman test results increased from 0.553 in 4 base compounds (without filler) to 0.701 in 16 compounds with filler. The difference in correlation coefficients show the necessity to use the effect of filler on calculating thermodynamic parameters in investigating moisture sensitivity of various asphalt mixes.     

Factors influencing capping and cracking of mefenamic acid tablets

The tendency of capping and longitudinal cracks of mefenamic acid tablets was evaluated in relation to the amount of the binder, the influence of the granulation technique, and the relative humidity of the granules. Tablets made from fluidized bed granules using methylcellulose in the granulating liquid showed significantly lower capping and longitudinal cracks than tablets from conventional granules prepared by wet granulation using methylcellulose as a dry binder.     

Factors Influencing Capping and Cracking of Mefenamic Acid Tablets

The tendency of capping and longitudinal cracks of mefenamic acid tablets was evaluated in relation to the amount of the binder, the influence of the granulation technique, and the relative humidity of the granules. Tablets made from fluidized bed granules using methylcellulose in the granulating liquid showed significantly lower capping and longitudinal cracks than tablets from conventional granules prepared by wet granulation using methylcellulose as a dry binder.