Fiber mat, method of making the fiber mat, and bituminous roofing product

Abstract

A fiber mat includes an assembly of fibers including a minority portion including a set of polymer fibers and a majority portion including a set of fibers different than the minority portion, wherein the minority portion is a plane parallel to a plane of the majority portion of the assembly of fibers; and a binder including an organic resin, wherein an air permeability of said fiber mat is not substantially different from an equivalent weight fiber mat containing a homogenous mat structure and wherein the fiber mat provides at least a 5% increase in tear when placed in a bituminous roofing product compared to an equivalent bituminous roofing product made with the equivalent weight fiber mat containing the homogenous mat structure.

What is claimed is: 
     
         1 . A fiber mat comprises:
 an assembly of chopped fibers comprising a minority portion and a majority portion, the minority portion forming a first layer and comprising a set of polymer fibers, and a majority portion forming a second layer and comprising a set of glass fibers, wherein at least the set of polymer fibers, the set of glass fibers, or combination thereof is blended with a set of natural fibers; and   a binder comprising an organic resin, wherein the fiber mat provides at least a 5% increase in tear when placed in a bituminous roofing product compared to an equivalent bituminous roofing product made with the equivalent weight fiber mat containing a homogenous mat structure.   
     
     
         2 . The fiber mat of  claim 1 , wherein the natural fibers comprise a basalt fiber, an animal-based fiber, a plant-based fiber, or combination thereof. 
     
     
         3 . The fiber mat of  claim 2 , wherein the natural fibers comprise a plant-based fiber. 
     
     
         4 . The fiber mat of  claim 1 , wherein the polymer fibers comprise polyester, polyethylene terephthalate, polyvinyl alcohol (PVA), polyvinyl chloride (PVC), polyether ether ketone (PEEK), polyether ketone (PEK), polyacrylonitrile, polystyrene, nylon, polymethyl methacrylate (PMMA), polybenzimidazole (PBI), polyimide, polyether imide (PEI), polyamide-imide (PAI), polyether sulfone (PES), polyphenyl sulfone (PPSU), polyphenylsulfide (PPS), liquid crystal polymer (LCP), ethylene tetrafluoroethylene (ETFE), polytetrafluoroethylene (PTFE), perfluoroalkoxy alkane (PFA), a blend, or combination thereof. 
     
     
         5 . The fiber mat of  claim 4 , wherein the polymer fibers comprise polyethylene terephthalate. 
     
     
         6 . The fiber mat of  claim 1 , wherein the polymer fibers are present at an amount of about 0.5 weight % to about 10 weight %, such as about 1 weight % to 5 weight %, such as about 1 weight % to about 3 weight % of the total weight of the assembly of fibers. 
     
     
         7 . The fiber mat of  claim 1 , wherein the set of polymer fibers of the minority portion comprises the polymer fibers blended with the natural fibers. 
     
     
         8 . The fiber mat of  claim 1 , wherein the minority portion is directly in contact with the majority portion at an interface, wherein the interface has a substantially distinct segregation between the minority portion and the majority portion. 
     
     
         9 . The fiber mat of  claim 1 , wherein a center plane of the minority portion is closer in distance to one surface of the fiber mat. 
     
     
         10 . The fiber mat of  claim 1 , wherein a center plane of the minority portion is approximately coincident to a center plane of the fiber mat. 
     
     
         11 . The fiber mat of  claim 1 , wherein the minority portion comprises a substantially random orientation of chopped fibers. 
     
     
         12 . The fiber mat of  claim 1 , wherein the majority portion comprises a substantially random orientation of chopped fibers. 
     
     
         13 . The fiber mat of  claim 1 , wherein the set of glass fibers of the majority portion comprises the glass fibers blended with the natural fiber. 
     
     
         14 . The fiber mat of  claim 1 , wherein the binder is substantially uniformly distributed throughout the fiber mat. 
     
     
         15 . The fiber mat of  claim 1 , wherein the fiber mat has a tensile strength at least 80% of a value of tensile strength of a fiber mat of equivalent weight containing the homogenous mat structure. 
     
     
         16 . The fiber mat of  claim 1 , wherein the fiber mat has a tensile strength at least 80% of a value of tensile strength of a higher caliper fiber mat having the homogenous mat structure. 
     
     
         17 . The fiber mat of  claim 1 , wherein a bituminous roofing product comprising the fiber mat has a tear strength at least 80% of a value of tear strength of an equivalent bituminous roofing product comprising a higher caliper fiber mat having the homogenous mat structure. 
     
     
         18 . The fiber mat of  claim 1 , wherein the minority portion is less than 10 weight % of a total composition of the fiber mat. 
     
     
         19 . The fiber mat of  claim 18 , wherein the majority portion is greater than 90 weight % of a total composition of the fiber mat. 
     
     
         20 . The fiber mat of  claim 1 , further comprising at least one coating of asphalt.