Enter the multifunctional trifluoromethylated epoxy Resin: Excellent flame retardant, better dielectric, low thermal expansion, etc

In order to obtain epoxy resins with flame retardant, dielectric properties, and easier industrialization, thus meeting the future development requirements in the field of electronic encapsulation, a trifluoromethylated epoxy resin (DGEBAF) was synthesized by using a two-step method, and the cured epoxy resin (DGEBAF/DDM) was prepared with DDM as the curing agent. Detailed studies of DGEBAF/DDM including curing kinetics, mechanical properties, and dielectric properties, etc. were conducted by using DGEBA/DDM (with dimethyl structure in DGEBA) and DGEBF/DDM (with dihydrogen structure in DGEBF) as the comparative samples. The results indicate that DGEBAF/DDM has higher storage modulus and strength, better dielectric properties, and hydrophobicity, and lowest thermal expansion coefficient, due to the existence of trifluoromethyl. Importantly, deeply study about the flame retardancy and its mechanism of DGEBAF/DDM was processed, which was of great significance for its application in the field of electronic packaging. Its vertical combustion level reaches UL-94 V-0. The limiting oxygen index of DGEBAF/DDM is 34.5 %, which is improved by 35.8 % and 30.2 % compared to DGEBA/DDM and DGEBF/DDM, respectively. The thermal decomposition mechanism of DGEBAF was explored by Py-GC/Mass, XPS, and FTIR analysis. It can be inferred that trifluoromethylated epoxy resin releases •CF3 at high temperatures and effectively enhances the flame retardant of the epoxy resin through radical trapping. The smoke toxicity of DGEBAF/DDM combustion was detected in real time by conical thermal method combined with gas infrared analysis. In addition, we have found that DGEBAF/DDM decomposes at first but produces most residual carbon among the three epoxy resins. Based on the characteristics, an intelligent fire alarm system was designed.