Rapid Microwave-Promoted Synthesis of Polyurethanes from a Fluorene Unit-Containing Diol and Diisocyanates
✍ Scribed by Kazuaki Hiroki; Yuichi Ichikawa; Hiroshi Yamashita; Jun-ichi Sugiyama
- Publisher
- John Wiley and Sons
- Year
- 2008
- Tongue
- English
- Weight
- 180 KB
- Volume
- 29
- Category
- Article
- ISSN
- 1022-1336
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
A fluorene diol derivative, 9,9‐bis[4‐(2‐hydroxyethoxy)phenyl]fluorene (1), reacted with diisocyanates such as 1,3‐bis(isocyanatomethyl)cyclohexane (2a), 1,6‐diisocyanatohexane (2b), and 1,3‐bis(isocyanatomethyl)benzene (2c) under temperature‐controlled microwave irradiation to form the corresponding polyurethanes with $\overline M _{\rm w}$ being 30 000 to 60 000, measured by GPC with reference to polystyrene standards within 5 to 10 min at 160 to 200 °C. In the reactions of 2a and b, the molecular weights were 15 to 20 times higher than those obtained by conventional oil bath heating. For a solvent of the microwave‐promoted reaction, a hydrocarbon compound, decalin, is preferably used to undergo the polymerization cleanly without unfavorable coloration and/or gelation.
magnified image