Composite material containing wet-laid nonwoven fabric and method for producing same

Abstract

Proposed are a composite material containing inorganic fibers and a method for producing the same. A composite material according to the present disclosure produced by mixing a wet-laid nonwoven fabric including inorganic fibers with a resin can exhibit excellent physical properties in terms of tensile strength and flexural strength.

What is claimed is: 
     
         1 . A composite material, comprising:
 a wet-laid nonwoven fabric; and   a resin,   wherein the wet-laid nonwoven fabric includes inorganic fibers.   
     
     
         2 . The composite material of  claim 1 , wherein the inorganic fibers include basalt fibers, silicon/carbon (Si/C) fibers, glass fibers, carbon fibers, or a combination thereof. 
     
     
         3 . The composite material of  claim 1 , wherein the inorganic fibers include recycled fibers. 
     
     
         4 . The composite material of  claim 1 , wherein the inorganic fibers have an average length of equal to or greater than 20 mm. 
     
     
         5 . The composite material of  claim 1 , wherein the resin includes an epoxy resin, a phenolic resin, a polyester resin, a silicone resin, a polyethylene resin, a polypropylene resin, a polystyrene resin, a polycarbonate resin, a polyamide resin, a polyurethane resin, or a combination thereof. 
     
     
         6 . The composite material of  claim 1 , wherein the wet-laid nonwoven fabric has an average pore size of equal to or greater than 10 μm as measured by a Pore size Measurement Instrument (PMI) analysis according to ASTM F316. 
     
     
         7 . The composite material of  claim 1 , wherein the wet-laid nonwoven fabric has a weight retention of equal to or greater than 90% as measured by thermogravimetric analysis (TGA) according to KS M ISO 11358-1. 
     
     
         8 . The composite material of  claim 1 , wherein the wet-nonwoven fabric has a machine direction (MD) tensile strength of equal to or greater than 30 N as measured at a test speed of 100 mm/min according to KS K ISO 9073-3, and a cross direction (CD) tensile strength of equal to or greater than 30 N as measured at a test speed of 100 mm/min according to KS K ISO 9073-3. 
     
     
         9 . The composite material of  claim 1 , wherein the wet-laid nonwoven fabric has a bursting strength of equal to or greater than 50 kPa as measured at a hydraulic pressure increase rate of 98 mL/min according to KS K 06428.18.1 A. 
     
     
         10 . The composite material of  claim 1 , wherein a weight ratio of the inorganic fibers to the resin is 1:99 to 70:30. 
     
     
         11 . The composite material of  claim 1 , wherein the composite material has a tensile strength of equal to or greater than 80 MPa as measured according to ASTM D3039/D3039M-17. 
     
     
         12 . The composite material of  claim 1 , wherein the composite material has a flexural strength of equal to or greater than 50 MPa as measured according to ASTM D790-17. 
     
     
         13 . A method for producing a composite material, the method comprising:
 adding inorganic fibers, a wetting agent, and a dispersant to a solvent to prepare an inorganic fiber dispersion;   removing the solvent from the prepared fiber dispersion and performing forming and drying to produce a wet-laid nonwoven fabric; and   mixing the wet-laid nonwoven fabric with a resin to produce a prepreg.   
     
     
         14 . The method of  claim 13 , wherein the mixing of the wet-laid nonwoven fabric with the resin to produce the prepreg includes a hot melt method, a solution impregnation method, or a combination thereof. 
     
     
         15 . The method of  claim 13 , further comprising:
 stacking one or more layers of the prepreg and performing molding, cooling, and demolding.   
     
     
         16 . The method of  claim 15 , wherein the molding is performed at a temperature of 80° C. to 350° C. and a pressure of equal to or greater than 0.5 MPa.