Pultrusion is the process of pulling continuous fibres through a die or rollers to produce constant Profile composites.

Thermopreg™ is easily converted into composites by heating the material above the melting point (165°C) of PP from 392°F (200°C) to 428°F (220°C). The polypropylene flows under pressure to form the matrix of the composites.

Rovings are pulled from a package through a tensioning device and into an infrared or convection oven to heat the material from 200°C to 220°C.
The molten Thermopreg™ rovings are drawn over a series of heated impregnation bars before entering a cross head extrusion die.