Synthesis of Castor Oil-based Cationic Waterborne Polyurethane Emulsion and Its Application

Abstract

Castor oil-based cationic waterborne polyurethane (CWPU) was synthesized by pre-polymer process using castor oil (CO), poly(adipic acid-1,4-succinate diol) (PBA), isophorone diisocyanate (IPDI), and N-methyldiethanolamine (MDEA). The influences of the content of CO and MDEA on comprehensive performance and finished fabric properties of cationic waterborne polyurethane was investigated, especially the antibacterial properties of finished fabric. The CWPU latex particle size and its distribution decrease as the content of CO increased from 0wt% to 16.8wt%, and increases afterwards. The CWPU films show much higher thermal stability than cationic waterborne polyurethane without CO. The surface of fabrics was characterized by scanning electron microscope (SEM). The finished fabric surface is much smoother. In addition, the finished fabric with CWPU emulsion has better antibacterial property against E. coli and S. aureus. When MDEA content is 8%, the antibacterial rates of the two kinds of bacteria are 77.3% and 82.2%, respectively.

Keywords

cationic waterborne polyurethane / castor oil / fabric finishing / antibacterial