Cardanol

Chemists at The City College of New York have designed a molecule which has both water-adhering and water-repelling ends, from cardanol (the structure on the right), a naturally available material found in cashew nutshell liquid.

When mixed with water, the designer molecules formed a self-assembled structure called a micelle with a water-adhering exterior and water-repelling interior.

At 50^oC the micelles take on a 3-dimensional structure known as a vesicle that is about 200 times larger and more viscous. The molecules stick together enough to be draw out into a thin strand, just like glue.

Cooling the material allows the molecules to revert to their original micellar structure.

Heating causes the micelles to re-arrange themselves into an interlocking bi-layer which undergoes curvature. The structure is stabilized in part by the hydrogen bonding.

Reference
Vijai S. Balachandran, Swapnil R. Jadhav, Padmanava Pradhan, Sacha De Carlo, George John. Adhesive Vesicles through Adaptive Response of a Biobased Surfactant. Angewandte Chemie International Edition, 2010; DOI: 10.1002/anie.201005439

Further Reading
Detergents
Soaps and Saponification
Functional Groups
Percentage Composition
Intermolecular Forces
Intramolecular Forces

Study Questions

1. Identify the functional groups present in a molecule of cardanol.
2. Give the molecular formula for cardanol.
3. Calculate the percentage of carbon, hydrogen and oxygen present in a mole of cardanol.
4. On the molecular structure of cardanol, identify the water-adhering area and the water-repelling area.
5. What is the name given to a molecule that adheres to water?
6. What name is given to a molecule the repels water?
7. Draw a diagram to show how cardanol molecules could form a micelle.
8. Given the description of the behaviour of the designer molecule in the article above, in what ways do you think it differs from the structure of cardanol?