Reinforced Hollow Profiles

Abstract

A hollow lineal profile formed from a continuous fiber reinforced ribbon (“CFRT”) that contains a plurality of continuous fibers embedded within a first thermoplastic polymer matrix. To enhance the tensile strength of the profile, the continuous fibers are aligned within the ribbon in a substantially longitudinal direction (e.g., the direction of pultrusion). In addition to continuous fibers, the hollow profile of the present invention also contains a plurality of long fibers that may be optionally embedded within a second thermoplastic matrix to form a long fiber reinforced thermoplastic (“LFRT”). The long fibers may be incorporated into the continuous fiber ribbon or formed as a separate layer of the profile. Regardless, at least at a portion of the long fibers are oriented at an angle (e.g., 90°) to the longitudinal direction to provide increased transverse strength to the profile.

1 - 31 . (canceled) 
     
     
         32 . A method for forming a hollow profile that extends in a longitudinal direction, the method comprising:
 impregnating a plurality of continuous fibers with a thermoplastic matrix within an extrusion device;   consolidating the impregnated fibers to form a first ribbon in which the continuous fibers are oriented in the longitudinal direction;   pultruding the first ribbon and a plurality of long fibers through a die to form the hollow profile.   
     
     
         33 . The method of  claim 32 , wherein the continuous fibers, long fibers, or both, include glass fibers, carbon fibers, or a combination of glass and carbon fibers. 
     
     
         34 . The method of  claim 32 , wherein the thermoplastic polymer matrix includes a polyolefin, polyether ketone, polyetherimide, polyarylene ketone, liquid crystal polymer, polyarylene sulfide, fluoropolymer, polyacetal, polyurethane, polycarbonate, styrenic polymer, polyester, polyamide, or a combination thereof. 
     
     
         35 . The method of  claim 32 , wherein the first ribbon has a void fraction of about 2% or less. 
     
     
         36 . The method of  claim 32 , wherein a manifold assembly supplies the thermoplastic matrix to the extrusion device, the manifold assembly comprising branched runners through which the thermoplastic matrix flows. 
     
     
         37 . The method of  claim 32 , wherein the profile exhibits a flexural modulus and maximum flexural strength in the transverse direction, wherein the ratio of the flexural modulus to the maximum flexural strength is from about 50 to about 2200. 
     
     
         38 . The method of  claim 32 , wherein the profile exhibits a flexural modulus of about 2 Gigapascals or more. 
     
     
         39 . The method of  claim 32 , wherein the profile exhibits a maximum flexural strength of about 12 Megapascals or more. 
     
     
         40 . The method of  claim 32 , wherein the long fibers are embedded within a second thermoplastic matrix. 
     
     
         41 . The method of  claim 40 , wherein the second thermoplastic polymer matrix includes a polyolefin, polyether ketone, polyetherimide, polyarylene ketone, liquid crystal polymer, polyarylene sulfide, fluoropolymer, polyacetal, polyurethane, polycarbonate, styrenic polymer, polyester, polyamide, or a combination thereof. 
     
     
         42 . The method of  claim 32 , wherein about 10% or more of the long fibers are oriented at an angle relative to the longitudinal direction. 
     
     
         43 . The method of  claim 32 , wherein the profile has a generally rectangular shape. 
     
     
         44 . The method of  claim 32 , wherein the long fibers are included within a first layer of the profile and the first ribbon is included within a second layer of the profile, the first layer being positioned adjacent to the second layer. 
     
     
         45 . The method of  claim 44 , wherein the first layer forms an inner layer of the hollow profile. 
     
     
         46 . The method of  claim 45 , wherein the second layer extends substantially around the periphery of the first layer. 
     
     
         47 . The method of  claim 45 , wherein the second layer is located in one or more discrete regions adjacent to the first layer. 
     
     
         48 . The method of  claim 44 , wherein the second layer forms an inner layer of the hollow profile. 
     
     
         49 . The method of  claim 48 , wherein the first layer extends substantially around the periphery of the second layer. 
     
     
         50 . The method of  claim 48 , wherein the first layer is located in one or more discrete regions adjacent to the second layer. 
     
     
         51 . The method of  claim 32 , wherein the cross-section shape of the profile is substantially the same along the entire length of the profile. 
     
     
         52 . The method of  claim 32 , wherein the long fibers are included within the first ribbon.