Synthesis of citric acrylate oligomer and its in-situ reaction with chrome tanned collagen (hide powder)

The purpose of this study was to formulate the new combined system of acrylic and citric acids, which was prepared by free radical polymerization and esterification reaction at the same time to form citric-acrylate CAC oligomer. The presumable chemical structure of this oligomer and the reaction mechanism were investigated by different spectroscopic tools (H-1,C-13-NMR and ATR-IR), GPC and TGA/ DTA. The effect as masking agent of the eco-friendly oligomer (CAC) in the chrome tanning of the Collagen and the pickling of the hide was approached by the study of the hydrothermal and mechanical properties of in-situ treated/grafted chrome tanned Collagen (hide powder) and pickled hide, respectively. The use of citric acrylate CAC oligomer instead of the traditional strong acids resulted in significant improvement in chrome exhaustion and physical properties of the leather.