Development and Characterization of Genipin Cross-linked Gelatin Based Composites Incorporated with Vegetable-tanned Collagen Fiber (VCF)

Abstract

Collagen fibers obtained from solid fibrous wastes generated intannery have a high potential of being used in developing greencomposites. Earlier studies in our laboratory demonstrate thatnonwoven composites can be derived from collagen fibernetwork using paper-making technology. The purpose of thiswork was to fabricate green composites based on gelatin andvegetable-tanned collagen fibers (VCF), using a non-toxic andnaturally occurring compound, genipin, as cross-linking agent.VCF were obtained from split hide that has been tanned withvegetable tannins by mechanical milling technique. The VCFcontent in the networks of gelatin was varied from 10 to 40%(w/w) in dry weight relative to that of the gelatin. The structure,mechanical properties, thermal properties and water resistanceof the composite films have been investigated with Fouriertransform infrared spectroscopy (FTIR), mechanical testing,thermogravimetric analysis and swelling measurement. Theresults from those studies revealed that VCF and gelatin couldmix with each other homogeneously under alkaline conditionand the mechanical properties of the composite films at wet statewere improved significantly over that of pure gelatin film. Inaddition, the composite films showed higher water resistanceand thermal resistance than the control. FTIR analysisconfirmed the molecular interactions between gelatin and VCFand the formation of cross-links between primary amino groupson gelatin and VCF. Our results indicated that VCF can be usedas environmentally friendly and cost-effective potentialreinforcing agent for green composites, providing betterproperties than the original biopolymer matrix. The genipincross-linked gelatin/VCF composite film can be a promisingcandidate for the biomedical and packaging applications.