Leather-like materials and methods of making the same

Abstract

In one aspect, the disclosure relates to bio-based synthetic leathers comprising an organic layer comprising agricultural waste such as, for example, ground nutshells, nut hulls, or both, wherein the organic layer further comprises nanocellulose hydrogels and embedded natural fibers. In another aspect, the bio-based synthetic leathers further include a resin topcoat and a natural fabric backing. In yet another aspect, the bio-based synthetic leathers contain no animal products and are antimicrobial, biocompatible, and compostable. The bio-based synthetic leathers have excellent mechanical properties and can be produced without the use of environmentally harmful chemicals. Also disclosed are methods of making the bio-based synthetic leathers and articles comprising the bio-based synthetic leathers.

What is claimed is: 
     
         1 . A bio-based synthetic leather comprising:
 (a) an organic layer comprising ground nutshells, ground nut hulls, or both, at least one fatty acid, at least one texture-modifying additive, and a nanocellulose hydrogel;   (b) a resin topcoat; and   (c) an optional natural fabric backing.   
     
     
         2 . The bio-based synthetic leather of  claim 1 , wherein the ground nutshells, ground nut hulls, or both comprise pecan, peanut, cashew, walnut, or almond shells or hulls, or any combination thereof. 
     
     
         3 . The bio-based synthetic leather of  claim 1 , wherein the ground nutshells, ground nut hulls, or both comprise agricultural waste. 
     
     
         4 . The bio-based synthetic leather of  claim 1 , wherein the at least one fatty acid comprises lauric acid, capric acid, palmitic acid, stearic acid, myristic acid, oleic acid, or any combination thereof. 
     
     
         5 . The bio-based synthetic leather of  claim 1 , wherein the at least one texture-modifying additive comprises sodium alginate, pectin, or any combination thereof. 
     
     
         6 . The bio-based synthetic leather of  claim 1 , wherein the organic layer comprises embedded natural fibers. 
     
     
         7 . The bio-based synthetic leather of  claim 1 , wherein the natural fabric backing comprises a nonwoven, woven, or knitted fabric. 
     
     
         8 . The bio-based synthetic leather of  claim 1 , wherein the resin topcoat comprises a plasticized fatty acid. 
     
     
         9 . The bio-based synthetic leather of  claim 8 , wherein the plasticized fatty acid comprises lauric acid, capric acid, palmitic acid, stearic acid, myristic acid, oleic acid, or any combination thereof. 
     
     
         10 . The bio-based synthetic leather of  claim 1 , further comprising at least one natural pigment. 
     
     
         11 . The bio-based synthetic leather of  claim 1 , wherein the bio-based synthetic leather is antimicrobial, biocompatible, compostable, or any combination thereof. 
     
     
         12 . The bio-based synthetic leather of  claim 1 , wherein the bio-based synthetic leather is thermostable to at least 200° C. 
     
     
         13 . A method for making a bio-based synthetic leather, the method comprising:
 (a) grinding nutshells, nut hulls, or both to a fine powder;   (b) mixing the ground nutshells, nut hulls, or both with at least one fatty acid, at least one texture-modifying additive, a nanocellulose hydrogel, and a cross-linking agent to form a precursor mixture;   (c) transferring the precursor mixture to a mold;   (d) distributing natural fibers in the precursor mixture; and   (e) drying the precursor mixture and natural fibers in an oven to produce the synthetic leather.   
     
     
         14 . The method of  claim 13 , wherein the cross-linking agent comprises citric acid, diglycidyl ether of bisphenol A (DGEBA), or any combination thereof. 
     
     
         15 . The method of  claim 13 , further comprising removing the bio-based synthetic leather from the mold, drying the bio-based synthetic leather in a vacuum oven, and flattening the bio-based synthetic leather in a heat press at from about 100 to about 150° C. 
     
     
         16 . The method of  claim 13 , further comprising applying a resin topcoat comprising a fatty acid to the bio-based synthetic leather. 
     
     
         17 . The method of  claim 13 , further comprising plasticizing the fatty acid, wherein plasticizing the fatty acid comprises applying epoxied oil, heat, a chemical initiator, or any combination thereof to the fatty acid. 
     
     
         18 . The method of  claim 13 , further comprising applying a natural fabric backing to the bio-based synthetic leather using a biodegradable adhesive and a heat transfer sublimation process. 
     
     
         19 . An article comprising the bio-based synthetic leather of  claim 1 . 
     
     
         20 . The article of  claim 19 , wherein the article comprises an article of clothing, luggage, a handbag, furniture, automotive upholstery, marine upholstery, aircraft upholstery, an article of footwear, athletic equipment, a watch band, or any combination thereof.