Epoxy Filament Winding System (Wet Winding Grade)

Epoxy Filament Winding System (wet winding grade) is a two-part liquid epoxy system optimized for continuous fiber filament winding processes. The formulation achieves a mixed viscosity of 500-2,000 mPa·s at 25°C — providing sufficient fiber tension control and impregnation at winding bath temperature (20-40°C) while maintaining a long pot life of 6-24 hours for uninterrupted production runs on large mandrels.

The system is based on BPA epoxy with a blend of modified cycloaliphatic and aliphatic amine hardener to balance pot life, cure speed, and final mechanical properties. Key performance characteristics include fiber volume fractions of 60-70% achievable at 3-8 MPa winding tension, low void content (<2%), and cured laminate properties of tensile strength >900 MPa (hoop), flexural modulus >35 GPa, with Tg reaching 120-140°C after post-cure at 80-120°C.

Filament winding applications include pressure vessels (CNG cylinders, hydrogen storage tanks, fire extinguisher cylinders), pipe and tube manufacturing, structural poles, masts, and aerospace pressure vessel structures. The system is compatible with E-glass, S-glass, carbon fiber, and basalt fiber with standard aqueous sizing systems. Mandrel release is facilitated by the smooth resin surface finish and controlled shrinkage during cure.