| 초록 |
Waterborne polyurethanes (WPU) were prepared by the prepolymer mixing process using isophorone diisocyanate, poly(tetramethylene ether) glycol, and 2,2-dimethylolpropionic acid. Ethylene diamine, diethylene triamine, and triethylene tetramine were used as chain extenders. The effects of the number of functional groups in these chain extenders on the properties of WPU films were investigated. The formation of the urea bond caused by the reaction between the residual NCO of the prepolymer and the amine group of the chain extender was confirmed through fourier-transform infrared spectroscopy. In addition, the rough surface of the WPU film was characterized by atomic force microscopy and scanning electron microscopy. The tensile strength, elongation, and gloss of WPU film as a function of the chain extenders. In particular, the gloss of WPU decreased as the number of functional groups of the chain extender increased, which is suitable for application in matting coating. |
