Patent ID: 7951317

Claim:
A process for manufacturing a composite part formed by the association of a theimoplastic polypropylene matrix reinforced with long glass fibers, said process comprising: supplying a thermoplastic polypropylene resin and high density glass granules to an injection or injection-compression device containing a single screw, said high density glass granules having a density or glass content between 90 and 99.5% and a length/diameter ratio L/D less than L, expressed in mm; wherein said high density glass granules are Ruined from chopped fiber strands having lengths between 6 and 30 mm, said high density glass granules having a length substantially identical to that of the length of the longest of said chopped strands; said high density glass granules being formed by mixing sized chopped fiber strands, water and optionally an ethylene vinyl acetate binding agent, wherein said sized chopped fiber strands are formed by mixing long fiber glass filaments coated with a sizing liquid including, based on the solids content of the sizing liquid, 10 to 99 wt. % of a member selected from the group consisting of an aqueous emulsion of an ethylene-vinyl acetate copolymer having an ethylene content of 50% or higher and an aqueous emulsion of an ethylene-acrylic acid copolymer having an ethylene content of 50% or higher; 1 to 30% of an aqueous emulsion of a maleic-anhydride-grafted polypropylene; and 1 to 40% of one or more organosilanes, at least one of which is an aminosilane.