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101.
The properties of poly(vinyl acetate) compositions prepared as potential wood adhesives were investigated. The paper presents the results of the influence of various kinds of inorganic fillers based on calcium carbonate and alumino-silicate and an organic filler, starch, on the adhesive composition properties. The comparison among rheological behavior of the adhesive dispersions concerning the specific role of fillers were made. Mechanical and relaxation properties of the adhesive films could reveal the effect of filler characteristics on the polymer matrix. The significant influences of particle size distribution and specific surface area on the poly(vinyl acetate) adhesive composition were determined, along with other filler characteristics.  相似文献   
102.
快固化淀粉粘合剂的研究   总被引:3,自引:0,他引:3  
介绍了快固化玉米淀粉粘合剂的制备工艺,对制备参数进行了优化,可使粘合剂的初粘速度和干燥速度显著提高。  相似文献   
103.
聚醋酸乙烯乳液缩醛化的改性研究   总被引:4,自引:1,他引:4  
本文介绍了为提高聚醋酸乙烯乳液稳定性、耐水性和防冻性而进行缩醛化改性的原理,并确定了最佳工艺条件即甲醛与聚乙烯醇的配比为0.45~0.50。  相似文献   
104.
This paper presents an experimental investigation into various aspects of epoxy-bonded polymethylmethacrylate (PMMA) and PMMA-to-aluminium joints. The effects of adhesive thickness, overlap area, surface roughness, and environmental exposure on the joint strength were studied. Results indicated that the joint strength was not directly proportional to the overlap area, while sanding had a positive effect on the joint strength. A negative effect was observed when adhesive thickness was increased. The fatigue behaviour of adhesively-bonded joints under dynamic loading was found to be independent of frequency, for the range of values tested; however, it was dependent on the test temperature with greater reduction in fatigue life observed in PMMA-to-aluminium joints at higher temperature. Empirical equations from which the fatigue life of joints can be predicted were obtained by regression analysis. Intermittent fatigue testing of the joints was also performed. The epoxy adhesive tested proved to be a satisfactory choice for outdoor exposure. The rate of degradation of the adhesive was slow with the adherend itself degrading at a faster rate than the adhesive or the bondline.  相似文献   
105.
环戊二烯及其在涂料,胶粘剂中的应用   总被引:3,自引:0,他引:3  
本文阐述了环戊二烯的性质,化学反应特点及用其改性醇酸脂和制造气干型不饱和聚酯等情况。  相似文献   
106.
王灿  刘秀生  郑芝国  高万振 《粘接》2005,26(5):8-10
详述了用于低表面能材料粘接的新型胶粘剂的制备过程,探讨了低表面能胶粘剂的粘接机理,并讨论了弹性体、三乙基硼烷胺络合物、丙烯酸单体等对低表面能材料胶粘强度的影响.  相似文献   
107.
TPR处理剂的研究   总被引:1,自引:0,他引:1  
利用活性单体苯乙烯与氯丁橡胶、高苯乙烯热塑弹性体接枝聚合,所得产物稀释后用于TPR(ThermalPlasticRubber)粘接前的预处理,可明显提高剥离强度。  相似文献   
108.
聚酯酰胺热熔胶的合成及其性能研究   总被引:2,自引:1,他引:2  
研究了以聚酯胶和聚酰胺胶为原料在催化剂作用下加热共熔,通过大分子链交换反应制备织物用聚酯酰胺热熔胶的方法。用聚酯胶的溶剂对所得产品进行溶取试验并且通过红外光谱分析都证明了链交换反应的存在。用该法所得产品粘接强度大,既耐水洗又耐干洗,适用于粘合衬生产。  相似文献   
109.
Epoxy adhesives filled with four different volume fractions of eutectic tin-bismuth solder alloy were prepared and the effect of filler content on the electrical and mechanical properties of these anisotropic electrically conductive adhesives was investigated. The results show that the adhesive containing the lowest amount of the filler alloy had the best combination of conductivity, insulation resistance and shear strength. The DSC-measurements suggested that the filler melts before the cure of the resin begins which allows the filler to wet and bond well to the conductors. This was verified by SEM/EPMA examinations. A temperature cycling test and high humidity, high temperature treatment were conducted on the best composite adhesive. The temperature variation had no effect on conductivity of the joints while humid and hot environment decreased the conductivity.  相似文献   
110.
The viscoelastic and peeling properties of polybutadiene/tackifying resin compatible blends have been studied in detail. Viscoelastic properties have been described through the variations of the complex shear modulus, G*(ω), as a function of frequency, ω and peeling properties through the variations of peeling force (F) as a function of peeling rate (V).

After showing the objective character of the peeling curves obtained, the variations of the peeling force and peeling geometry have been studied as a function of volume fraction of the tackifying resin.

In this first paper, the analysis is focused on the first domain of the peeling curves, i.e. the cohesive fracture region. In this region, the peeling properties have been related to the viscoelastic properties in the terminal region of relaxation. It is shown that the longest relaxation time, τo, is a reducing parameter of the peeling curves, so a peeling master curve-which is independent of temperature, resin volume fraction and polymer molecular weight-may be defined. Furthermore, the variations of the test geometry as a function of peeling rate have been investigated: the variations of the radius of curvature of the aluminium foil have been analyzed with respect to the viscoelastic behavior of the adhesive, which in fact governs the test geometry.

A detailed analysis of all these features leads to a model which allows one to calculate the peeling curves in the cohesive domain from the adhesive formulation.  相似文献   
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