초록 |
Polyurethanes (PUs) are connected by urethane units formed by the reaction between hydroxyl groups and isocyanate groups. Elastomeric PU is one of versatile polymers for automotive parts, medical devices, and sports goods due to the physical properties of PU adjustable with wide range of raw materials and processing parameters. Recently, we have found that urethane units formed by the reaction between aromatic isocyanate and cycloaliphatic diol such as isosorbide show reversible features above 150℃. Thus, we have prepared modeling compound from 4, 4’-phenyl methane diisocyanate and isosorbide and investigated the dynamic features employing FT-IR spectrometry and TGA. These assessments revealed that the dynamic urethane bonds were affected by the catalysts used for the preparation of the PU as well as the temperatures. Such dynamic covalent bonds may be useful for the design of self-healing polyurethanes. |