Abstract

The retanning process is one of the most important processes in leather production and which plays a vital role in the modern leather industry. In this paper, copolymers based on acrylic acid (AA), butyl acrylate (BA) and acrylamide (AM), were prepared by free radical polymerization. Chain transfer agents were added during the synthesis process to control the molecular weight of the copolymer. The copolymers with different amounts of chain transfer agent were tested for their molecular weight and other properties. The copolymers were analysed using XRD, GPC and FT-IR.

Leathers were retanned with different copolymers and the mechanical properties, and SEM of retanned leather were also examined. The results showed that the increased molecular weight of the copolymers decreased the crystallinity, the functional groups of copolymers did not change significantly when the dosage of chain transfer agents increased. When the amount of chain transfer agents was increased, the copolymer had a smaller molecular weight and the retanned leather showed better elongation at break. When the copolymer molecular weight was larger, the tensile strength and tear strength of retanned leather increased. This is important to help select the appropriate molecular weight acrylic retanning agent for different styles of leather products.