Greener Solutions 2016: Safer PHA/PHB colorants for marine buoys

Mango Materials, of Berkeley, CA,  makes the biopolymers PHA (Poly-hydroxyalkanoate ) and PHB (poly-hydroxybutryate) from waste methane. The Mango team was challenged to investigate colorants because while PHA is biodegradable, many of the substances added to it for application performance are not and some of the currently used industrial colorants have properties that are cause for concern. Iron oxide red, for example, is persistent in the environment and has shown evidence of carcinogenic effects.

The Mango team researched several areas in order to prescribe their opportunity map for the company: the PHA substrate, marine buoys and their environments, colorants and current manufacturing processes. The marine buoy application challenge had exacting performance requirements: the same colors that had to be bright, highly visible and long-lasting, also had to be biodegradable and benign. They turned to natural dyes and sources of pigments, recommending paprika, curcumin, chlorophyll and calcium carbonate as substitutions for currently used red, yellow, green and white colorants.