Fiber reinforced thermoplastic sheets with surface coverings

Abstract

A composite sheet material in one embodiment includes a porous core layer. The porous core layer includes a thermoplastic polymer, about 20 weight percent to about 80 weight percent of reinforcing fibers based on a total weight of the porous core layer, and an effective amount of a flame retardant agent.

1 - 29 . (canceled) 
     
     
         30 . A thermoplastic composite comprising a web comprising a plurality of reinforcing fibers of a first composition, a thermoplastic resin present to hold the reinforcing fibers together, and at least one additional type of fiber with a different composition than the first composition. 
     
     
         31 . The thermoplastic composite of  claim 30 , in which the web comprises a polyetherimide polymer. 
     
     
         33 . The thermoplastic composite of  claim 30 , in which the web comprises a polycarbonate polymer. 
     
     
         34 . The thermoplastic composite of  claim 30 , in which the plurality of reinforcing fibers are glass fibers. 
     
     
         35 . The thermoplastic composite of  claim 30 , in which the web comprises about 20 weight percent to about 80 weight percent of reinforcing fibers based on a total weight of the composite. 
     
     
         36 . The thermoplastic composite of  claim 30 , in which the at least one additional type of fiber is effective to enhance the cohesion of the web. 
     
     
         37 . The thermoplastic composite of  claim 30 , in which the plurality of reinforcing fibers have a length between 7-200 mm. 
     
     
         38 . The thermoplastic composite of  claim 30 , in which the web is substantially void free. 
     
     
         39 . The thermoplastic composite of  claim 30 , in which the composite comprises a maximum Ds of 200 or less at 4 minutes as tested by ASTM method E-662. 
     
     
         40 . The thermoplastic composite of  claim 30 , in which the composite comprises a heat release of less than 65 kW/-min/m2 under FAR 25.853(a). 
     
     
         41 . The thermoplastic composite of  claim 30 , in which the composite does not include a flame retardant. 
     
     
         42 . A method of forming a thermoplastic composite comprising:
 forming a web comprising an aqueous suspension of a thermoplastic resin, a plurality of reinforcing fibers of a first composition and a plurality of additional fibers of a second composition different than the first composition;   heating the web to remove any liquid and melt the fibers;   cooling the web to provide a composite comprising the plurality of reinforcing fibers of a first composition and the plurality of fibers of the second composition that are held together by the thermoplastic resin.   
     
     
         43 . The method of  claim 38 , further comprising using a wet laid process to form the composite. 
     
     
         44 . The method of  claim 38 , in which the web is heated above the glass transition temperature of the thermoplastic resin.