Investigation of utilization of tanned leather wastes in making composite materials

Leather industry solid wastes have some unique properties that enable them regenerative characteristics. These leather wastes are composed of chemically stabilized and durable fibrous structure and so their biodegradability is questionable. A cost effective and eco benign alternative method to disposal of these wastes is to reuse them. In this research, chromium tanned leather fibers were used as a filler and reinforcement fragments in polymeric matrixes for several composite applications providing environmental compatibility. For the production of composites using leather wastes, the effect of the parameters including tanning agent kind and concentration, fatliquor concentration, binder concentration and kind, fiber kind were investigated. In the trials for tanning agent kind and concentration, it was understood that lignosulfonate gives the product better strength properties and an increase was found in the physicomechanical properties with the increase of tanning agents content between 3-15 %. To understand the effect of fatliquor concentration on the composite; 4 % was the optimum concentration. For the binder, stress and strain properties of the product increased with increasing concentration between 9-18 % and natural latex gave the best results as polymer matrix. For the fiber kind, it was found out that the combination of leather fiber with other fibers, especially with paper fibers, increased the product properties. As a result, it was pointed out that regenerated materials having leather-like properties could be produced with polymers reinforced with fibers obtained from solid leather wastes.