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The Electrically Conductive Adhesives(ECAs) has better printing performance than the solder paste, which can meet the requirements of higher precision. In this paper, three different kinds of organic matter were used as curing agents in an ECAs to find out the effect on that. The effect of curing agent on the conductive properties of silver paste ECAs has been systematically investigated by volume resistivity test, and the curing loss rate was used to indicate the curing properties. In addition, the mechanical properties on different curing time were analyzed by comparing the shear stress through shear strength test. The analysis of volume resistivity test indicated that extension curing time will make the unevenness of silver particle become larger, which can benefit the conductivity of silver paste ECAs. Whats more, and the result of shear strength tests show that when curing time up to 20 minutes, the shear strength of containing triethanolamine and dicyandiamide silver paste ECAs will be more than 10MPa when curing time up to 20 minutes. The curing loss rate indicate that the silver paste ECAs which contains triethanolamine is the most stable one.

Silver paste electrically conductive adhesives (ECAs) are adhesives containing silver particles and resin matrix, forming by specific technology. The conductive adhesive has better printing performance than the solder paste, which can meet the requirements of higher precision. However, the relationship between curing process and properties of conductive adhesive has not been developed completely and it is time to explore a kind of conductive adhesive which is suitable for fast curing. The effects of curing time and temperature of conductive adhesives on electrical and mechanical properties are studied in this paper. Several analysis methods are used to test scanning electron microscope photograph, electrical and mechanical properties and so on. Besides, the TG and DSC curves are studied to seek the appropriate curing temperatures of three conductive adhesives with different volume percentages. The curing process has influence on the electrical and mechanical properties of the conductive adhesive after curing. When the curing temperature is lower than the temperature of the crosslinking reaction, the curing process is not complete, and the resistivity shows large. The shear strength of the conductive adhesive increases with the increase of curing time. The conductive adhesive can be cured completely when the curing temperature reaches the temperature of crosslinking reaction and the resistivity decreases with the increase of the curing temperature. The shear strength increases with the increase of curing time in the initial stage of curing process and the conductivity and shear strength begin to decrease when the curing time reaches a certain range. Curing temperature over 140°C can be difficult to get good conductivity and shear strength.

Jet printing technology solves the problem of control of solder paste's height in screen printing and it is also suitable for soft substrate printing, which may possible make it have wide application in complex integrated circuit. Conductive adhesive is a kind of adhesive containing conductive particles and resin matrix, forming by specific technology. The ECAs own better printing performance than the solder paste, which meeting the requirements of higher precision. However, jet printing technology of ECAs has not been developed completely and it is time to explore a kind of conductive adhesive which is suitable for jet printing and fast curing at the same time. The effects of different components of ECAs on printing are studied in this paper. Different analysis methods were used to test viscosity, scanning electron microscope photograph, jet printing performance and so on. Besides, the rheological behavior, morphology, points dimension were studied in printing performance. Compared with the conductive adhesive containing triethanolamine which could be printed well, the conductive adhesives containing methyl hexahydrophthalic anhydride and dicyandiamide are difficult to be printed. According to the results of viscosity test, when the shear rate is low, the viscosity-shear rate curves of conductive adhesives which contain triethanolamine and dicyandiamide are similar, which means that they own the similar rheological properties.

The conductive filler in the Electronic Conductive Adhesives(ECAs) have been widely investigated for decades. In this paper, the mass fraction of silver powder ranging from 30% to 50% was added as conductive filler into ECAs. To study the influence of the content of the conductive filler, volume resistivity, shear strength and jet printing test were carried out to assess the conductivity, shear stress and the shape of jetting dots, respectively. According to the percolation theory and the result of conductivity test, it reached its percolation when the mass fraction of silver powder increased up to 40%, and the shear strength decreased as the mass fraction of silver powder progressively increased. The result of jet printing test showed that the probability of contact between silver particles increased with the content of silver powder increasing, which results in jam problem.

Alloy powder is the main material of solder and the type, shape, size distribution and content will affect the rheological properties of the paste, thereby affecting the printing performance of the solder paste. A comprehensive research of the complicated interactions among these factors will be very essential to develop high performance solder pastes for future jetting. This paper investigates the rheology behavior and stability of Sn-3Ag-0.5Cu and Sn-58Bi lead-free solder pastes with various fluxes. Besides, the type, shape, size distribution and content of the alloy powders' impact on the rheology behavior and stability have also been discussed and analyzed in this article.

The pyrolysis oil from lignocellulosic biomass as a renewable resource has been exploited and utilized. Microbial degradation of the pyrolysis oil by several fungi strains was investigated. The results showed that Trichoderma viride, Aspergillus niger, Trichoderma harzianum, Penicillium oxalium and Phanerochaete chrysosporium could grow well using the pyrolysis oil as carbon source, while the growth of plant pathogen Cladosporium cucumerinum and Botrytis cinerea was inhibit by the pyrolysis oil. HPLC analysis showed that some water-soluble compounds in pyrolysis oil are biodegradable.