Epoxy Prepreg System (Autoclave/OOA Grade)

Epoxy Prepreg System is a formulated epoxy resin system designed for impregnation of carbon, glass, or aramid fiber reinforcements to produce pre-impregnated composite materials (prepregs) for autoclave and out-of-autoclave (OOA) curing processes. The system is based on multifunctional epoxy components (BPA epoxy + epoxy novolac modifier) with DICY/accelerator or aromatic amine cure technology to achieve the required combination of tack, drape, out-time, and cured laminate properties.

The resin system is characterized by semi-solid state at room temperature (solid content >95%, tackiness at 20-25°C), supporting lay-up of complex contoured parts without resin drainage. Out-time at room temperature is 20-30 days for standard grades and 45-60 days for extended out-time formulations. Autoclave cure at 120°C/2h gives Tg 120-135°C; 180°C/2h cure gives Tg 175-195°C for high-temperature structural applications.

OOA grades are formulated with controlled resin flow and a vacuum bag-only (VBO) cure mechanism using dry fiber channels for air evacuation, producing void content <1% without autoclave pressure. These enable high-quality composite structures in tooling, large aircraft structures, and wind energy components where autoclave size or cost prohibit conventional autoclave processing.