System for producing a fully impregnated thermoplastic prepreg

Abstract

According to one embodiment, a system for manufacturing a fully impregnated thermoplastic prepreg includes a mechanism for moving a fabric or mat and a drying mechanism that removes residual moisture from at least one surface of the fabric or mat. The system also includes a resin application mechanism that applies a reactive resin to the fabric or mat and a press mechanism that presses the coated fabric or mat to ensure that the resin fully saturates the fabric or mat. The system further includes a curing oven through which the coated fabric or mat is moved to polymerize the resin and thereby form a thermoplastic polymer so that upon exiting the oven, the fabric or mat is fully impregnated with the thermoplastic polymer. During at least a portion of the process, humidity in the vicinity of the coated fabric or mat is maintained at substantially zero.

What is claimed is: 
     
         1 . A thermoplastic prepreg comprising:
 a fabric or mat; and   a thermoplastic material that impregnates the fabric or mat of fibers, the thermoplastic material comprising thermoplastic polymers that are formed by polymerization of monomers or oligomers in which greater than 95 percent of the monomers or oligomers polymerize to form the thermoplastic polymer; wherein:   the fabric or mat is fully and completely impregnated with the thermoplastic material; and   when subjected to a subsequent heating and/or pressure process, the thermoplastic polymer melts or softens to allow the thermoplastic prepreg to be molded or formed into a composite part.   
     
     
         2 . The thermoplastic prepreg of  claim 1 , wherein greater than 98 percent of the monomers or oligomers polymerize to form the thermoplastic polymer. 
     
     
         3 . The thermoplastic prepreg of  claim 1 , wherein the thermoplastic prepreg is post-polymerizable to further increase the polymerization of the monomers or oligomers and/or molecular weight of the thermoplastic polymer. 
     
     
         4 . The thermoplastic prepreg of  claim 1 , wherein the fabric or mat comprises chopped fibers or a hybrid of different type of fibers. 
     
     
         5 . The thermoplastic prepreg of  claim 1 , wherein the fibers of the fabric or mat are sized with one or more coupling agents that covalently bond the thermoplastic material to the fibers. 
     
     
         6 . The thermoplastic prepreg of  claim 5 , wherein the one or more coupling agents includes coupling-activator compounds having a silicon-containing moiety and an activator moiety. 
     
     
         7 . The thermoplastic prepreg of  claim 5 , wherein the one or more coupling agents include blocked isocyanate coupling compounds having a silicon-containing moiety and a blocked isocyanate moiety. 
     
     
         8 . The thermoplastic prepreg of  claim 1 , wherein the thermoplastic prepreg includes multiple layers of the fabric or mat that are each fully and completely impregnated with the thermoplastic material. 
     
     
         9 . The thermoplastic prepreg of  claim 1 , wherein the thermoplastic polymers include polyamides, polyesters, and blends of thermoplastic polymers. 
     
     
         10 . The thermoplastic prepreg of  claim 9 , wherein the thermoplastic polymers consist of polyamide-6. 
     
     
         11 . A thermoplastic prepreg comprising:
 a fabric or mat; and   a thermoplastic material that impregnates the fabric or mat of fibers, the thermoplastic material comprising thermoplastic polymers that are formed by polymerization of monomers or oligomers in which greater than 95 percent of the monomers or oligomers polymerize to form the thermoplastic polymer; wherein:   the fabric or mat is fully and completely impregnated with the thermoplastic material; and   the thermoplastic prepreg is moldable or formable into a composite part.   
     
     
         12 . The thermoplastic prepreg of  claim 11 , wherein greater than 98 percent of the monomers or oligomers polymerize to form the thermoplastic polymer. 
     
     
         13 . The thermoplastic prepreg of  claim 11 , wherein the thermoplastic prepreg is post-polymerizable to further increase the polymerization of the monomers or oligomers and/or molecular weight of the thermoplastic polymer. 
     
     
         14 . The thermoplastic prepreg of  claim 11 , wherein the fabric or mat comprises chopped fibers or a hybrid of different type of fibers. 
     
     
         15 . The thermoplastic prepreg of  claim 11 , wherein the fibers of the fabric or mat are sized with one or more coupling agents that covalently bond the thermoplastic material to the fibers. 
     
     
         16 . The thermoplastic prepreg of  claim 15 , wherein the one or more coupling agents includes coupling-activator compounds having a silicon-containing moiety and an activator moiety. 
     
     
         17 . The thermoplastic prepreg of  claim 15 , wherein the one or more coupling agents include blocked isocyanate coupling compounds having a silicon-containing moiety and a blocked isocyanate moiety. 
     
     
         18 . The thermoplastic prepreg of  claim 11 , wherein the thermoplastic prepreg includes multiple layers of the fabric or mat that are each fully and completely impregnated with the thermoplastic material. 
     
     
         19 . The thermoplastic prepreg of  claim 11 , wherein the thermoplastic polymers include polyamides, polyesters, and blends of thermoplastic polymers. 
     
     
         20 . The thermoplastic prepreg of  claim 11 , wherein the thermoplastic polymers are formed by anionic polymerization of monomers or oligomers.