Preparation and properties of rosin-based cationic waterborne polyurethane dispersion

Green renewable resource has become a global hot spot. In this study, naturally occurring resource rosin derivative (RAG) was used to prepared a cationic waterborne polyurethane (WPU) dispersion using n-methyl di-ethanolamine (MDEA) as an ion center and 1,3-bis(3-aminopropyl) tetramethydisiloxane (APTMDS) as a chain extender, and hexamethylene diisocyanate (HDI) as a hard segment. The effects of MDEA and APTMDS contents on the particle size and storage stability of the WPU dispersion was determined, in addition, thermo-mechanical and mechanical properties, and antibacterial property as well as water uptake of the resulting polyurethane films were thoroughly investigated. The results show that an increase in the APTMDS content considerably improved the mechanical properties, surface hydrophobicity and water resistance of the WPU films. Moreover, all WPU films exhibit enhanced antibacterial activity against Escherichia coli and Staphylococcus aureus with the increase in the MDEA and APTMDS contents. Graphical abstract