Biodegradable polymers
Bacterial polyesters, polyhydroxyalkanoates, are potentially a replacement for common thermoplastics.
Degradation of polymers
Biodegradable polymers are produced as response to nutrient limitation by many micro-organism to provide energy storage from catabolism. The most common of this class of polymers are co-polymers of polyhydroxybutyrate and polyhydroxyvalerate. Because of their biological origin, they have enhanced environmental degradation properties with respect to commom plastics based on polyolefins. Biopolymers may degrade completely in the environment in time-scale much shorter than for polyolefins. Despite their appeal, biopolymers are not used extensively yet due to their high production costs and their limited processing windows. One key issue is the degree of crystallinity and foamability, which is critical for processing. Crystallinity and density of polymers can be studied efficiently by scattering methods. This thesis topic is offered in collaboration with Chris Garvey from TUM / MLZ.