The aim of the research project is a renewable soil release coating for efficient application on textile floor coverings in the contract sector. This soil release coating is based on nanocrystalline cellulose (NCC) with polyphosphoester (PPE) functionalities on the surface to be specially designed, whose functional properties are controlled by the environmental conditions (dirigated functional nanocellulose).

PE groups in the main chain of the PPE functionalities lead to the flame retardant property of such a coating. Hydrophobic, pH-switchable groups in the side chains of the PPE functionalities enable the formation of reversible physical bonds between different dirigated functional nanocelluloses as well as between dirigated functional nanocellulose and hydrophobic wear layer of the floor covering. As a result, the soil release coating has a high abrasion resistance and barrier effect under application conditions.

During basic cleaning, alkali-activatable nucleophiles in the side chains induce hydrolysis of the PPE functionalities; in addition, the bonds formed by the pH-switchable groups are broken. Therefore, the coating of the dirigated functional nanocelluloses are detached from the flooring as anionic, short-chain, water-soluble, biodegradable polymer segments as well as NCC. Due to the emulsification of detached soil by the NCC, soil re-deposition is prevented.

The project results provide a soil release coating that significantly reduces the effort required for cleaning and maintenance of textile floor coverings, does not impair the flame retardancy of coated floor coverings, meets the requirements of the bioeconomy and does not result in microplastic emissions.