| High Density Interconnect/Build-up Multilayers (HDI/BUM) have been extensively used in high speed digital and high frequency microwave electrical products. The insulation inks are the key materials for the manufacturing of HDI/BUM, and the epoxy resins are the main materials for producing insulation inks. However, epoxy resin has some undesirable properties, such as a high dielectric constant, high dissipation factor and low thermal stability, which have limited the application of epoxy resin in insulation inks for high performance HDI/BUM. In this dissertation, multi-functional O-cresol Formaldehyde Epoxy resin (OCFEP) was modified and used as the main material for insulation ink. A new thermosetting resin (NSMA) was synthesized with N-phenylmaleimide, styrene andd maleic anhydride and the properties and curing behavior of the NSMA/OCFEP system were intensively studied. Furthermore, the effects of cyanate ester prepolymer (PCE) on the properties of the NSMA/OCFEP system and the properties and curing behavior of PCE/OCFEP system were analyzed. The synthesis and properties of weakly alkaline water soluble o-cresol formaldehyde epoxy acrylate and the effects of PCE/NSMA/OCFEP system on properties of UV cuing insulation ink were also discussed. Based on above works, the application and composition of insulation inks for HDI/BUM were investigated.NSMA was synthesized and characterized with infrared spectroscopy. Number average molecular weight, weight average molecular weight and molecular-weight distribution of NSMA determined by gel permeation chromatograph were 2.33×105, 59.5×105 and 2.56, respectively. NSMA was studied by means of differential scanning calorimetry (DSC) and it was found that the glass transition temperature (Tg) of NSMA increases with the increasing of N-phenylmaleimide content. Under PCE content of 53.78wt.%, the Tg of NSMA reached 234℃. The thermal degradation process of NSMA was studied and it was found that the activation energy was 211.34kJ/mol according to the Flynn-Wall-Ozawa method and the thermal degradation was a first-order chemical reaction.The curing behavior of NSMA/OCFEP system was studied by nonisothermal DSC and isothermal DSC methods. The DSC curves of NSMA/OCFEP system had two obvious exothermal peaks, indicating the curing mechanism was complicated. Based on the results of the Kissinger method, the activation energy values of two reaction steps were 39.46kJ/mol and 78.07kJ/mol respectively. The results were in agreement with the activation energy values (49.83kJ/mol and 77.66kJ/mol, respectively) calculated by isoconversional method. The isothermal curing reaction of NSMA/OCFEP system exhibited an autocatalytic behavior and was composed of a chemical reaction step and a diffusion control step. The curing reaction can be well described by applying the Kamal kinetics model at the high temperature. However, There existed some errors between the experimental and theoretical data at low temperature.The thermal properties of PCE/OCFEP system were studied and its Tg was more than 170℃, increasing more 40℃than that of conventional epoxy resin system. The dielectric constant (1MHz), dissipation factor (1MHz) and peel strength of the heat curing insulation ink based NSMA/OCFEP system is 3.7, 0.016 and 8.5 N/cm, respectively. The peel strength was increased by 53% when PCE/OCFEP system at PCE of 12wt.% and its ielectric constant (1MHz) is less than 3.6, dissipation factor (1MHz) less than 0.015 and Tg more than 180℃.The curing behavior, heat property, dielectric property and mechanical property of PCE/OCFEP system had been intensively studied in this work. The apparent activation energy values of PCE/OCFEP system at PCE contents of 80wt.%, 60wt.% and 40wt.% are 83.22, 66.32 and 78.48kJ/mol respectively, and the reaction is first-order chemical reaction. Based on the requirement for application, the optimum technical parameters for the PCE/OCFEP curing system is 130℃/1h+140℃/1h+180℃/1h and the Tg of cured material is more than 180℃.The dielectric performance of PCE/OCFEP system at different PCE contents was also studied. The theoretical dielectric constant is higher than the experimental value when PCE content is more than 50wt.% and is lower than the experimental value when PCE content is less than 50wt.%. This is caused by much more triazine formed. Due to the system containing foreign particles, the theoretical value of the dissipation factor is more than the experimental value. Liquid butadiene-acrylonitrile (CTBN) and nano-SiO2 modified PCE/OCFEP were investigated and their mechanical properties were remarkably superior to that of the modified PCE/OCFEP.Maleic anthydride modified o-cresol formaldehyde epoxy acylate prepolymer was synthesized, effects of catalysts, catalysts contents, reaction temperature and time on the reaction were systematically investigated. The optimized reaction conditions were obtained as following: the catalyst is tetramethylammonium chloride, the amount of tetramethylammonium chloride is 1.0wt.%, the reaction temperature is 80-100℃, the time is 4.5-5h. The effect of the ratio of maleic anthydride and o-cresol formaldehyde epoxy acylate on the resistance to acid and ankali of the system, the apparent kinetics and the influence of prepolymer and monomer on surface drying were analyzed. The UV curing behavior of photo-imagleable ink prepared by maleic anthydride modified o-cresol formaldehyde epoxy acylate prepolymer was studied by infrared spectroscopy and it was found that after a 15s exposure, the conversion of unsaturation exceeds 80%, and the curing conversion leads to 85%. The content of PCE/NSMA/OCFEP on the properties photo-imagable insulation ink was also investigated. The Tg, dielectric constant (1MHz), dissipation factor (1MHz) and peel strength of the inks are 160℃,4.0, 0.027 and 12N/cm, respectively, at the content of PCE/NSMA/OCFEP of 40wt.%.The application, preparation and composition of insulation ink for HDI/BUM were introduced and the application problems were analyzed in the last.
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