Jennifer A Ward

US Patent:

20080237914, Oct 2, 2008

Filed:

Mar 26, 2008

Appl. No.:

12/079340

Inventors:

Arnold Lustiger - Edison NJ, US
Jennifer Harting Ward - Houston TX, US
Patrick Bormann - Caudebec, FR
David Jon Starz - Baytown TX, US
Alan J. Oshinski - League City TX, US

International Classification:

B29B 9/06
B29C 47/60

US Classification:

264143

Abstract:

The present disclosure is directed generally to methods for making fiber reinforced polypropylene composite pellets using pre-cut fiber fed to a compounding extruder by improved fiber feeder systems. One form of the method includes feeding into a compounding extruder at least 25 wt % polypropylene based polymer, from 5 to 60 wt % pre-cut organic fiber, and from 0 to 60 wt % inorganic filler; and extruding, cooling and pelletizing the resultant mixture of components to form fiber reinforced polypropylene composite pellets; wherein the pre-cut organic fiber is fed from a feeder including a feeder hopper, one or more conditioning augers/agitators, one or more metering augers below the feeder hopper, and a means for controlling the speed of the conditioning augers/agitators and metering augers; and wherein an article molded from the pellets has a flexural modulus of at least 2.07 GPa and exhibits ductility during instrumented impact testing. In another form, the feeder includes a feeder hopper, two or more counter-rotating metering rollers, one or more separating rollers below the metering rollers, and a means for controlling the speed of the metering rollers and separating rollers. In yet another form, a circle feeder may be used to feed the pre-cut fiber.