| 초록 |
Waterborne polyurethane dispersions (PUDs) were prepared using polycarbonate-diols, 4,4′-methylenebis(cyclohexyl isocyanate), and dimethylol propionic acid with dibutyltin dilaurate catalyst. The PUDs were synthesized by acetone process and then finely dried to make the PU films. In order to clarify how the mechanical properties of the polyurethanes are influenced by the length of soft-segment and the relative amount of hard-segment, we synthesized the PUDs using two different polycarbonate-diols, whose molecular weight were 1085 and 2028. The ratio of hard-segment to soft-segment of the PUDs was further modulated by using two types of chain extender, 1,4-butanediol and ethylene diamine. Using FT-IR analysis, we performed the semi-quantitative analysis of urea, urethane, methylene, and carbonate groups in the PUDs. The effect of the molar length of PC-diol and the NCO/OH ratio on the mechanical properties of the PU films were characterized using UTM measurement. |
