Summary: | The aim of this paper is the obtaining of value-added products from the dust resulted from chamois leather buffering, a solid waste that raises serious disposal problems, due to its physical state and complex chemical composition. Starting from leather waste, an alkaline hydrolysis was performed followed by the chemical modification of the polypeptyde hydrolysate by polycondensation with dispersions of copolymers of vinyl acetate with acrylic esters and reticulation with glutaraldehyde in order to improve its hydrophobicity. The resulted product can be used/was tested as an ingredient in leather finishing formulations, as binder or carrier agent. In this paper, new finishing mixtures were prepared using pigments and obtained polypeptide hydrolysates as a substitute for casein in pigment pastes. By this method, there were obtained two experimental variants of brown and black pigment pastes which were compared to the pigment pastes with casein binder. Natural grain Box bovine leather samples coated with such admixtures were subjected to physico-mechanical resistance tests, in accordance with the standardized methods. Specific tests carried on finished leather – tensile strength, tear resistance, resistance to grain cracking, dry and wet rubbing fastness, flexural fatigue strength test, etc – showed values of this characteristics comparable to those obtained with casein conventional finishing.
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