Synthesis and properties of two novel silicon‐containing cycloaliphatic epoxy resins for electronic packaging application

In this paper, two silicon‐containing cycloaliphatic olefins were synthesized through the nucleophilic substitution reactions of cyclohex‐3‐enyl‐1‐methanol with di‐ or tri‐chlorosilane compounds. Then, after epoxidation, two new cycloaliphatic epoxy resins with different epoxy groups were successfully prepared. Their chemical structures were confirmed by ²⁹Si NMR, ¹H NMR, and Fourier‐transform infrared spectra (FTIR). The properties of cured products, including viscoelasticity, glass transition temperature (T_g), coefficient of thermal expansion, thermal stability and water absorption, were investigated. Compared to the difunctional epoxy resin, the trifunctional one exhibited a remarkably increased cross‐linking density from 0.82 to 4.08 × 10^?3 mol/cm³ and T_g from 157 to 228°C. More importantly, prior to curing, they had viscosities of only 240–290 mPa sec at 25°C, which were much lower than that of ERL‐4221 (409 mPa sec), providing the possibility of easy processing. The high glass transition temperatures, good thermal stabilities, and mechanical properties as well as excellent flowability endow the silicon‐containing epoxy resins with promising potential in microelectronic packaging application. Copyright © 2011 John Wiley & Sons, Ltd.