High performance fiber reinforced thermoplastic resin, method and apparatus for making the same

A process for producing a molded article made of fiber-reinforced thermoplastic material, the process comprising the steps of:

• admixing thermoplastic material in its solid state with reinforcing fibers, wherein the thermoplastic material has a melt flow index of at least 25 g/10 minutes according to ASTM D1238, and consists of at least one of the group which includes polyamides, polyesters, polyolefins, polycarbonates, thermoplastic polymer alloys, and wherein the reinforcing fiber has an average length of at least 0.375 inch and are sized with a material which contains at least one polymer selected from the group consisting of polyurethane, polyurea, isocyanate derivatives of polyurethane and isocyanate derivatives polyurea, wherein the reinforcing fibers are filamentized in an essentially homogenous dispersion throughout the solid polymeric material;
• knead melting the admixed thermoplastic material and oriented reinforcing fibers for an interval sufficient to achieve melting of the thermoplastic material, wherein the knead melting step occurs in a device capable of achieving a compression ratio between 2.0:1 and 2.9:1;
• transferring the knead melted material into a suitable closed cavity mold device;
• and
• upon solidification, removing a finished article from the mold device.

A process for producing a molded article made of fiber-reinforced thermoplastic material, the process comprising the steps of:

• admixing thermoplastic material in its solid pelletized state with glass reinforcing fibers, wherein the thermoplastic material contains a major portion of polypropylene and a minor portion of functionalized polypropylene, the thermoplastic material having a melt flow index of at least 25 g/10 minutes according to ASTM D1238, and wherein the glass reinforcing fibers have an average length greater than 0.375 inch and are present in an amount greater than 30% by weight, the glass reinforcing fibers are sized with a material which contains at least one compound selected from the group consisting of polyurethane, polyurea, isocyanate derivatives of polyurethane, and isocyanate derivatives of polyurea, and wherein the glass reinforcing fibers and the thermoplastic material are subjected to centrifugal orientational agitation in the vertical axis such that the glass reinforcing fibers are filamentized in an essentially homogenous dispersion throughout the solid pelletized polymeric material;
• knead melting he admixed thermoplastic material and oriented reinforcing fibers for an interval sufficient to achieve melting of the thermoplastic material, wherein the knead melting step occurs in a device capable of achieving a compression ratio between 2.0:1 and 2.9:1;
• transferring the knead melted admixture into a suitable mold device;
• and
• removing a finished article from the mold device.

An article composed of an injection moldable polymeric material, the injection moldable polymeric material comprising:

• a melt processible thermoplastic material having a melt flow index of at least 25 g/10 minutes according to ASTM D1238;
• reinforcement fibers having a cumulative length distribution frequency is at least 5% of fibers having lengths 10 mm, the reinforcement material having a sizing compound associated therewith, the sizing compound including at least one polymer from the group consisting of polyurethane, polyurea, and isothiocyanate derivatives thereof, the reinforcing material is present in an essentially uniformly dispersed manner in which individual fibers in a filamentized manner in an amount greater than 30% by weight;
• and
• wherein the article has at least one cantilever and a tensile strength at break at least 20,000 psi.