| 초록 |
Polyurethanes (PU) are very versatile materials with a wide range of physical and chemical properties. They are composed of hard and soft segments. The hard segments consist of diisocyanate and chain extender and act as thermally reversible crosslinks. The soft segments consist of glycol and constitute soft domains which impart polyurethanes elastic properties. PU were synthesized from poly(ε-caprolactone) diol, 1,4-butandiol, and three different diisocyanates, 4,4′-Methylenebis(phenyl isocyanate) (MDI), 1,5-naphtalene diisocyanate (NDI), and 1,4-phenylene diisocyanate (PPDI). In this study, Effects of different diisocyanates on the mechanical and thermal properties of PU were investigated. It was found that PU based on MDI showed remarkable strain induced crystallization compared with PUs based on NDI or PPDI. |
