Retanning agent for chrome tanned leather based on modern technique of emulsion polymers

Retanning process aims at filling up of the meatuses of the already tanned leather through the incorporation of vegetable or synthetic tannins or polymer (resins) with the aim of giving more fullness and improving to the final product. So using of the emulsion polymer of poly(methyl methacrylate-co-butyl acrylate) prepared with in situ nano-silica as a modern retanning agent of chrome tanned leather to totally replace chrome salt and to enhance physical, thermal shrinkage, and mechanical properties of the final tanned leather as well as to reduce the environmental impact of chrome tanning effluent. Polymer/nanosilica hybrid emulsions were prepared via in situ seed emulsion polymerisation. The prepared polymers were characterised for solid content, molecular weight, viscosity, drying time, minimum film-forming temperature (MFFT) and microstructures (via TEM). The mechanical, shrinkage, thermal and surface morphological (by SEM) properties of the treated samples were also investigated. The influences of the increase in the content of organic nano-silica on the properties of the retanned leather are discussed.

Automated summary

The retanning process aims to fill the pores of already tanned leather with vegetable or synthetic tannins or polymers, in order to improve fullness and final product properties, while reducing the environmental impact of chrome tanning. The use of polymer/nanosilica hybrid emulsions as a modern retanning agent shows potential in enhancing physical, thermal, and mechanical properties of the leather, as well as reducing environmental impact. The study discusses the effects of organic nano-silica content on the properties of the retanned leather.