After enhancing its reactivity, cardanol is chemically bonded with cellulose, which produces a durable thermo-plastic that is strong, heat resistant, water resistant and non-crystalline (short molding time), due to the bonded cardanol's unique molecular structure consisting of flexible and rigid parts.

ENGADGET: NEC builds a better bioplastic from plant stems and cashew nut shells

And it's believed that the high chemical reactivity of the surface is due to the deposition of chemically active gases from the atmosphere onto the surface, gases like hydrogen peroxide and ozone.

NPR: Revisiting the Viking Missions to Mars