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 fully impregnated thermoplastic prepreg formed by a method comprising:
 moving a fabric or mat from a starting point to an ending point;   drying the fabric or mat to remove residual moisture from the fabric or mat;   mixing a liquid or molten resin with a catalyst or an activator via a mixing component to form a reactive resin mixture, the catalyst or activator facilitating in polymerizing the liquid or molten resin to form a thermoplastic polymer;   applying the reactive resin mixture to the fabric or mat via a resin applicator that is positioned above the fabric or mat so that the reactive resin mixture is applied to the fabric or mat as the fabric or mat is passed under the resin applicator;   blowing, via a gas application mechanism, a moisture-free gas onto one or more surfaces of the fabric or mat after application of the reactive resin mixture and prior to passing the fabric or mat through a curing oven, the moisture-free gas being blown onto the fabric or mat to substantially prevent exposure of the reactive resin mixture to ambient moisture in a surrounding environment;   passing the fabric or mat through a calendar or press to press the reactive resin mixture entirely through the fabric or mat such that the reactive resin mixture saturates the fabric or mat; and   passing the fabric or mat through the curing oven to polymerize the reactive resin mixture and thereby form the thermoplastic polymer;   wherein the mixing component and the resin applicator are heated to maintain the resin in a liquid or molten state.   
     
     
         2 . The thermoplastic prepreg of  claim 1 , wherein a portion of the liquid or molten resin is mixed with the catalyst in a first tank and a portion of the liquid or molten resin is mixed with the activator in a second tank that is separate from the first tank, and wherein mixing the liquid or molten resin with the catalyst and the activator comprises mixing the materials from the first tank and the second tank in the mixing component. 
     
     
         3 . The thermoplastic prepreg of  claim 1 , wherein the mixing component and the resin applicator are heated to between 70 and 120 degrees Celsius. 
     
     
         4 . The thermoplastic prepreg of  claim 1 , wherein nitrogen gas is applied to the one or more surfaces of the fabric or mat. 
     
     
         5 . The thermoplastic prepreg of  claim 1 , wherein passing the fabric or mat through the calendar or press and passing the fabric or mat through the curing oven comprises passing the fabric or mat through a double belt compression oven. 
     
     
         6 . The thermoplastic prepreg of  claim 1 , wherein the method further comprises winding the fully impregnated thermoplastic prepreg into a roll product. 
     
     
         7 . The thermoplastic prepreg of  claim 1 , wherein greater than 95% of the liquid or molten resin is polymerized to form the thermoplastic polymer. 
     
     
         8 . The thermoplastic prepreg of  claim 1 , wherein the reactive resin mixture having a viscosity of 10 centipoises or less. 
     
     
         9 . The thermoplastic prepreg of  claim 1 , wherein the liquid or molten resin comprises caprolactam. 
     
     
         10 . A fully impregnated thermoplastic prepreg formed by a method comprising:
 drying a fabric or mat to remove residual moisture from the fabric or mat;   applying a liquid or molten resin to the fabric or mat via a resin applicator;   passing the fabric or mat through a calendar or press to saturate the fabric or mat with the resin; and   passing the fabric or mat through a curing oven to polymerize the resin and thereby form a thermoplastic polymer; and   controlling an ambient moisture level in a vicinity of the fabric or mat to substantially prevent exposure of the liquid or molten resin to excess moisture.   
     
     
         11 . The thermoplastic prepreg of  claim 10 , wherein the method further comprises blowing, via a gas application mechanism, a moisture-free gas onto one or more surfaces of the fabric or mat after application of the liquid or molten resin and prior to passing the fabric or mat through a curing oven to substantially prevent exposure of the liquid or molten resin to ambient moisture in a surrounding environment. 
     
     
         12 . The thermoplastic prepreg of  claim 11 , wherein the gas application mechanism is positioned such that the moisture-free gas is blown onto the one or more surfaces of the fabric or mat between the resin applicator and the curing oven. 
     
     
         13 . The thermoplastic prepreg of  claim 10 , wherein the method further comprises combining a catalyst or an activator with the liquid or molten resin prior to applying the liquid or molten resin to the fabric or mat. 
     
     
         14 . The thermoplastic prepreg of  claim 10 , wherein the fabric or mat includes sized fibers containing an activator and wherein the method includes applying the liquid or molten resin to the fabric or mat made of the sized fibers. 
     
     
         15 . The thermoplastic prepreg of  claim 10 , wherein the method further comprises winding the fully impregnated thermoplastic prepreg into a roll product. 
     
     
         16 . The thermoplastic prepreg of  claim 10 , wherein the liquid or molten resin comprises caprolactam. 
     
     
         17 . The thermoplastic prepreg of  claim 10 , wherein passing the fabric or mat through the calendar or press and passing the fabric or mat through the curing oven comprises passing the fabric or mat through a double belt compression oven. 
     
     
         18 . A fully impregnated thermoplastic prepreg formed by a method comprising:
 drying a fabric or mat to remove residual moisture from the fabric or mat;   applying a reactive resin to the fabric or mat as the fabric or mat is passed under a resin applicator;   applying a moisture-free gas onto one or more surfaces of the fabric or mat after application of the reactive resin;   passing the fabric or mat through a calendar or press to saturate the fabric or mat with the reactive resin; and   passing the fabric or mat through a curing oven to polymerize the reactive resin and thereby form a thermoplastic polymer;   wherein the resin applicator is heated to maintain the reactive resin in a liquid or molten state.   
     
     
         19 . The thermoplastic prepreg of  claim 18 , wherein applying a moisture-free gas comprises blowing, via a gas application mechanism, the moisture-free gas onto the one or more surfaces of the fabric or mat to substantially prevent exposure of the reactive resin to ambient moisture in a surrounding environment. 
     
     
         20 . The thermoplastic prepreg of  claim 18 , wherein greater than 95% of the reactive resin is polymerized to form the thermoplastic polymer.