A high-performance renewable thermosetting resin derived from eugenol.
A renewable bisphenol, 4,4'-(butane-1,4-diyl)bis(2-methoxyphenol), was synthesized on a preparative scale by a solvent-free, Ru-catalyzed olefin metathesis coupling reaction of eugenol followed by hydrogenation. After purification, the bisphenol was converted to a new bis(cyanate) ester by standard techniques. The bisphenol and cyanate ester were characterized rigorously by NMR spectroscopy and single-crystal X-ray diffraction studies. After complete cure, the cyanate ester exhibited thermal stability in excess of 350 °C and a glass transition temperature (Tg ) of 186 °C. As a result of the four-carbon chain between the aromatic rings, the thermoset displayed a water uptake of only 1.8% after a four day immersion in 85 °C water. The wet Tg of the material (167 °C) was only 19 °C lower than the dry Tg , and the material showed no significant degradation as a result of the water treatment. These results suggest that this resin is well suited for maritime environments and provide further evidence that full-performance resins can be generated from sustainable feedstocks.
Research Department, Materials Chemistry Branch, US Navy, Naval Air Warfare Center, Weapons Division (NAWCWD), 1900 N. Knox Rd. Stop 6303, China Lake, CA 93555 (USA). benjamin.g.harvey@navy.mil.
Benjamin G
BG
Harvey
Christopher M
CM
Sahagun
Andrew J
AJ
Guenthner
Thomas J
TJ
Groshens
Lee R
LR
Cambrea
Josiah T
JT
Reams
Joseph M
JM
Mabry
D005054:Eugenol / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D010636:Phenols / Q000737:chemistry; D012117:Resins, Synthetic / Q000737:chemistry*; D013696:Temperature
D010636:Phenols; D012117:Resins, Synthetic; D005054:Eugenol
biomass; coupling reaction; materials science; polymers; renewable resources