Synthesis and properties of an epoxy resin containing trifluoromethyl side chains and its cross-linking networks with different curing agents

The epoxy resin with a trifluoromethyl side chain, (3-trifluoromethyl) phenylhydroquinone epoxy resin (3F-PQE), was synthesized via a three-step procedure. The chemical structures were confirmed by FT-IR, 1H NMR, 13C NMR and elemental analysis. A series of trifluoromethyl epoxy networks has been prepared with four curing agents: poly (propylene glycol) bis (2-aminopropy) ether (D230), 2-methylimidazole (2MI), 4, 4-methylene-dianiline (DDM) and phthalicacidanhydride (PA). All samples exhibited excellent thermal stabilities (the decomposition temperature of 5% weight loss (Td)) ranged from 335 to 362 °C in N2 and 291-355 °C in air). The 3F-PQE-DDM sample showed the highest Tg of all the samples. Moisture absorption of 3F-PQE-DDM and 3F-PQE-PA at 80 °C for 24 h was no more than 1 wt %. The cured fluorinated epoxy resins exhibited that the contact angles were more than 90°, which is the hydrophobic properties.