Abstract:
A high-reactivity aliphatic amine curing agent (type 593), a volatile solvent (propylene glycol methyl ether), and an epoxy monomer (bisphenol A diglycidyl ether) were combined into a novel system (denoted as Ink), which enables rapid curing, phase separation, and solvent removal at room temperature. Using the polymerization-induced phase separation technique, blind-pore type epoxy cured films were fabricated through Ink dwell and film dwell at 25 ℃, followed by a final high-temperature curing step. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), phase contrast microscopy, and optical microscopy were employed to investigate the curing reaction, phase separation process, and morphological evolution. Results showed that when the film dwell time was fixed at 120 min, the average pore diameters of the blind-hole type epoxy films obtained with Ink dwell times of 60 min and 120 min were 0.50 μm and 0.87 μm, respectively, indicating that extending the Ink dwell time increased both pore diameter and depth. Moreover, a through-pore type epoxy cured film was obtained by using deionized water as an antisolvent to promote phase separation. This process significantly simplifies the preparation of porous epoxy cured films.