Controlled geometry composite micro pellets for use in compression molding

摘要

Controlled geometry pellets, which have at least one generally flat face having a cross-sectional shape with a rectangular envelope having an aspect ratio of at least 1.5, are provided. The controlled geometry pellets may include a plurality of reinforcing particulates dispersed throughout the thermoplastic resin. The reinforcing particulates typically have a largest dimension which is no more than about 90% of the largest pellet dimension. Compression molding methods of manufacturing a shaped article using the pellets are also provided. The methods include compression molding thermoplastic resin-based material to provide a molded article, where thermoplastic resin-based material comprises a plurality of the controlled geometry pellets.

主权项

1. Composite pellets produced by a method comprising:
extruding a blended mixture comprising molten thermoplastic resin and reinforcing fibers through a die orifice with a cross-sectional shape having a rectangular envelope with an aspect ratio of about 1.5:1 to 5:1, wherein the reinforcing fibers have a largest dimension which is no more than about 90% of a width of the die orifice; and cutting the extruded mixture to form pellets having an axial length to cross-sectional width ratio of about 0.25:1 to 5:1; wherein the reinforcing particulates comprise carbon fibers having a diameter of about 5 to 20 microns and an aspect ratio of about 10 to 200; and the thermoplastic polymeric resin comprises polyetheretherketone, polyetherketoneetherketoneketone, polyetherimide, polyethersulfone, polyphthalamide or a combination thereof.