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With the rapid development of the field of electronic tip as well as lead-free solder, the cured encapsulating material in Universal epoxy its heat resistance and moisture resistance can not satisfy the technical requirements of the electronic packaging materials, and therefore, the development of having high heat resistance, low The water absorption rate of the epoxy resin has a very important significance, the biphenyl group is a highly rigid group, biphenyl group introduced in the epoxy resin skeleton, one can improve the heat resistance thereof; the other hand, can be reduced small free volume in order to improve toughness and reduce water absorption. 4,4 '- dimethoxy methyl biphenyl and phenol as raw material obtained by the condensation reaction of biphenyl phenolic resin, then of the biphenyl phenolic resin and epichlorohydrin (ECH) is the raw material, synthetic biphenol formaldehyde epoxy resin. The synthesis of epoxy resins by infrared spectroscopy, hydrogen NMR spectrum, epoxy equivalent measurement confirmed its structure. By the choice of synthesis conditions biphenyl phenol resin and epoxy resin, include phenol ratio, reaction temperature, reaction time, catalyst type and amount, the order of addition, washing with water addition to the proportion of catalyst and ECH to obtain epoxy value in the range between 0.35 to 0.37 , the melt viscosity is between 50 ~ 150 mPa.s and an organic chlorine content lt; 700 ppm of the biphenyl epoxy novolac resin. Study the influence of the thermal performance of the cured product of a different molecular weight distributions, the study showed that the molecular weight distribution is smaller, and n = 1 structure biphenyl epoxy novolac resin content more the biphenyl epoxy novolac resin obtained by thermal gravimetric analysis (TGA) better thermal performance. 4,4 '- diaminodiphenyl sulfone (DDS), the the different cured product hydroxyphenylmaleimide (HPM), biphenyl the phenol (DPR), polyamide 650 (PA) as a curing agent compared the thermal performance and examine the gel time, the study found that the initial thermal decomposition temperature of the cured product as a curing agent to the DDS, HPM, DPR can be reached more than 370 ℃ at 700 ℃ residual mass fraction is 32%, 38% and 40%, respectively. Visits gel time of the four curing agent biphenyls phenolic epoxy optimum temperature of 190 ° C. to 210 ° C, 170 ° C. to 190 ° C from 200 ℃ to 220 ° C and of 50 ℃ ~~ 60 ° C, respectively. In addition, contrast biphenyl phenolic epoxy resin cured with ordinary epoxy resin cured product of the heat-resistant performance, the results show that the introduction of the biphenyl structure, greatly improving the heat resistance of the epoxy resin, and reducing the water absorption, there conducive used in the field of electronic packaging materials.
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