Epoxy resin compositions, epoxy resin compositions for fiber-reinforced composite materials, and fiber-reinforced composite materials comprising the same

摘要

An epoxy resin composition having a low viscosity around a room temperature and excellent reinforcing fiber impregnating properties provides a composite material having excellent heat resistance and mechanical properties including compressive strength. The epoxy resin composition includes an aromatic epoxy resin having at least di-functionality, an aromatic amine compound and/or an alicyclic amine compound, wherein 5 minutes after the main agent comprising the epoxy resin and the curing agent comprising the aromatic amine compound and/or the alicyclic amine compound are mixed, the composition shows a viscosity at 25° C. in the range of from 1 to 1500 mPa sec, and Tc, tc, and Tg satisfy the following equation (1):; $PTEXTHILITALICPDATTg\≧Tc\+/PDAT/ITALIC/HILPDAT20/PDATHILITALICPDAT\−k/PDAT/ITALIC/HILPDAT\×(/PDATHILITALICPDATTc\−/PDAT/ITALIC/HILPDAT90)\ \ (1),/PDAT/PTEXT$ ;wherein k=0 when 60≦Tc90 and k=0.35 when 90≦Tc≦200;;Tc is the highest temperature (°C.) during the curing process and is defined by the formula 60≦Tc≦200;;tc is the retention time (min) at the highest temperature and is defined by the formula 1≦tc≦120; and;Tg is the glass transition temperature of the epoxy resin composition after a lapse of tc (min) at Tc (°C.).