Cyanate esters are a remarkable family of compounds that exhibit many useful properties in the materials world. They retain their structural integrity into the 400⁰ C range, they have extremely low water uptake, making them ideal for corrosion-resistant coatings which the Navy requires for its sea-borne assets.

At China Lake we set out to create a compound with these properties that would make an attractive replacement for the current standard which is a primer laced with Chromium (a very toxic carcinogen). The structure shown above is the final product of our work which stemmed from an initial reaction using carvacrol. Carvacrol was attractive because of its structural similarity to carvone, limonene, and pinene. These chemicals, as their names imply come from and attribute to the aromas associated with caraway, citrus, and pine trees respectively. They are often the waste products of the industries that 

This is a Thermal Gravimetric Analysis (TGA) which shows our product’s high durability under intense heat. It retains almost all of its mass up until the 400⁰ C mark as is common for molecules of this family.

After sending our final product off for characterization, we set to work on finding a way to take one or all of these precursor molecules to complete synthesis. Using a series of small scale reactions, we were able to go from limonene to the final product with relative ease, thus showing the viability of this as a cheap and less toxic alternative coating methods. Current issues regarding our experiment center around high enough yields to be viable and taking pinene all the way to our finished compound. We were able to get small yields that would potentially work, but they were clouded by other isomers mixed in so a new reaction will need to be tried in order to get a more selective result.

Future Work
Now that the as of yet unnamed molecule has been characterized, we will continue to refine the overall reaction process to improve yield as well as find ways to selectively react our precursor molecules. From there our final challenge will be scaling the reaction up in size to accommodate for large scale production.

Written by Thomas Koontz