Preparation of Epoxy Resin Cured with Latent Curing Agent at Moderate Temperature
|Keywords||Epoxy resin Temperature curing Latent Curing kinetics Resin-modified|
The anisotropic conductive adhesive film (ACF) is composed of an anisotropic polymer film by the conductive particles, a binder, additives. ACF for the first time since the 1970s, since the liquid crystal display panel used to connect electronic calculator, with the rapid development of the information industry, has been widely used in various fields of LCD and integrated circuit involved. The conductive particles conferred ACF with conductive properties, a binder gives the ACF to connect the performance. The epoxy resin is a widely used thermosetting resin, the matrix resin of the ACF adhesive important, epoxy type ACF has a strong bond, the curing shrinkage is small, the resistance, good stability of chemical mediators, etc.. Traditional epoxy adhesive for high temperature curing adhesives, curing time was needed, the storage stability of the single-component poor. From a simple process, and prevent pollution pollution considering the latent curing agent, especially temperature curing latent curing agent has become the best choice. Further, the epoxy curing brittle nature, impact resistance, and poor weather resistance defects which hinder their application, there is a need to be appropriately modified in order to adapt to different needs of the epoxy resin. The subject first basic thermotropic liquid curing agent to select the appropriate temperature and fast curing agent as the E-51 main curing agent for epoxy resin systems. FT-IR scan of the sample before and after curing, the curing effect of the various curing system for comparison; reuse heating DSC method to track the whole process of curing, the curing temperature of the measurement of various curing agents; With isothermal DSC measured at different curing Finally, the curing time of the system; the curing agent for screening out the optimization of the amount and the curing temperature, to determine the optimal preparation of the optimization system. It was found that the E-51 epoxy resin temperature curing effect best imidazole curing agent, which 2 - methylimidazole (2-MI) curing the fastest, best equipped with E-51 epoxy The ratio of 7:100, and the curing temperature between 88.5 ℃ and 93.7 ° C. Get 2-MI/E-51 system of reaction process, using isothermal DSC method the optimized curing kinetics of the system studied. The study found that the curing kinetics of the system is a composite model that combines of Kamal composite model of the n-order kinetics and autocatalytic dynamics. Found by comparing the fitting result, the dominant autocatalytic dynamics in the kinetics of the reaction process of the composite model. In order to achieve the purpose of extension adhesives applicable, by the addition of a hyperbranched polyester epoxy matrix modified. Hyperbranched polyester vast network structure having a certain gap, the curing agent may \Low, hyperbranched polyester small molecule of the curing agent may be wrapped up, to maximize contact with the epoxy resin curing reaction, until the temperature is gradually increased, the viscosity of the system is reduced, and the beginning of the curing agent \\When the temperature was elevated to the solidification point, the curing reaction is started quickly, the system was quickly cured. The experimental results show that, in addition of the hyperbranched polyester, the medium-temperature fast curing adhesive systems in low temperature conditions can be stably stored more than 1 year; another hardness test showed that the modified also significantly improved the uniformity of the overall hardness of the cured system.