화학공학소재연구정보센터
Journal of Supercritical Fluids, Vol.107, 605-611, 2016
Insight into the role of potassium hydroxide for accelerating the degradation of anhydride-cured epoxy resin in subcritical methanol
Degradation of methyl-1,2-cyclohexanedicarboxylic anhydride (MeHHPA)-cured epoxy resin in subcritical methanol in the presence of potassium hydroxide (KOH) was studied. The degraded products of epoxy resin were first separated using vacuum distillation, extraction and preparative high-performance liquid chromatography (HPLC) and then characterized by HPLC, electrospray ionization mass spectrometry (ESI-MS), H-1 and C-13 nuclear magnetic resonance (NMR). The effects of temperature and KOH on the kinetic behavior of degradation and the product distribution were examined. The temperature for the complete degradation of epoxy resin decreased greatly after adding a small amount of KOH. Transesterification was the dominant mechanism of degradation of epoxy resin. Reaction between KOH and epoxy resin and transetherification mechanism were also proposed. KOH improved the reaction mainly as a catalyst with consumption of methanol but contributed little to the reaction as a reagent. The bending properties of recycled epoxy resin with degraded products obtained at different KOH concentrations were also examined. (C) 2015 Elsevier B.V. All rights reserved.