Apparatus and method for forming fiber filled thermoplastic composite materials

A method for producing a fiber reinforced thermoplastic material comprising

• providing an impregnation chamber having an elongate impregnation passageway with an entrance end and an exit end,
• directing a continuous filament fiber along a predetermined advancing path of travel into and through the passageway, entering through the entrance end and exiting through the exit end,
• directing molten thermoplastic polymer material into the impregnation passageway at a location adjacent the exit end thereof and in a direction toward the entrance end in opposing, counter-current relation to the advancing fiber and in intimate contact with the advancing fiber for wetting and impregnating the fiber with the thermoplastic material, and
• pulling the polymer impregnated fiber from the exit end of the impregnation passageway while maintaining tension on the advancing fiber in the impregnation passageway as it contacts the molten thermoplastic polymer.

Apparatus for producing a fiber reinforced thermoplastic material comprising

• an impregnation chamber having a vertically oriented, elongate impregnation passageway with an upper entrance end and a lower exit and,
• an exit die with a restricted die opening mounted at the lower exit end of the impregnation passageway,
• a supply of continuous filament fiber,
• means for directing the fiber along a predetermined advancing path of travel into and through said impregnation passageway, entering through said entrance end and exiting through the restricted die opening of said exit die,
• an extruder for providing a supply of molten, thermoplastic polymer under pressure,
• means for directing molten thermoplastic material from said extruder into said impregnation passageway at a location adjacent said exit end thereof so that the molten polymer flows upward in counter-current relation to the direction of the advancing fiber and in intimate contact with the advancing fiber whereby shear forces arising between the advancing fiber and the flow of thermoplastic material promote wetting and impregnating of the fiber with the molten thermoplastic polymer,
• a turning guide positioned within said passageway adjacent said exit end for engaging and turning the advancing fiber through a predetermined angle prior to passing through said exit die for squeezing the fiber and thermoplastic material together and assuring wetting of the fiber with the thermoplastic material, and
• means on the downstream side of said impregnation chamber for pulling the polymer impregnated fiber from the impregnation chamber and through said exit die and for maintaining tension on the advancing fiber in the impregnation passageway as it contacts the molten thermoplastic polymer.

Apparatus for producing a fiber reinforced thermoplastic material comprising

• an impregnation chamber having a plurality of elongate impregnation passageways, each with an entrance end and an exit end,
• a supply of a plurality of strands of continuous filament fiber,
• means for directing the strands of fiber along a predetermined advancing path of travel into and through respective ones of said impregnation passageways, each entering through said entrance end and exiting through the exit end,
• an extruder for providing a supply of molten, thermoplastic polymer under pressure,
• means for directing molten thermoplastic material from said extruder into each of said impregnation passageways at a location adjacent said exit end thereof so that the molten polymer flows along the respective passageways toward said entrance end thereof in countercurrent relation to the direction of movement of the advancing strands of fiber and in intimate contact with the respective advancing strands of fiber whereby shear forces arising between the advancing fiber and the flow of thermoplastic material promote wetting and impregnating of the strands of fiber with the molten thermoplastic polymer,
• at least one guide positioned for engaging and joining the polymer impregnated strands together into one bundle,
• and exit die with a restricted die opening through which the bundle of fibers passes, and
• means on the downstream side of said exit die for pulling the polymer impregnated fiber bundle from the impregnation chamber and through said exit die and for maintaining tension on the advancing strands of fiber in the impregnation passageway as they contact the molten thermoplastic polymer.

Apparatus for producing a fiber reinforced thermoplastic material comprising

• an impregnation chamber having an elongate impregnation passageway with an entrance end and an exit end,
• an exit die with a restricted die opening mounted at the exit end of said impregnation passageway,
• a supply of continuous filament fiber,
• means for directing the fiber along a predetermined advancing path of travel into and through said impregnation passageway, entering through said entrance end and exiting through the restricted die opening of said exit die,
• an extruder for providing a supply of molten, thermoplastic polymer under pressure,
• means for directing molten thermoplastic polymer material from said extruder into said impregnation passageway at a location adjacent said exit end thereof so that the molten polymer flows along the passageway toward said entrance end thereof in counter-current relation to the direction of movement of the advancing fiber and in intimate contact with advancing fiber and the flow of thermoplastic material promote wetting and impregnating of the fiber with the molten thermoplastic polymer, and
• means on the downstream side of said impregnation chamber for pulling the polymer impregnated fiber from the impregnation chamber and through said exit die and for maintaining tension on the advancing fiber in the impregnation passageway as it contacts the molten thermoplastic polymer.