The biodegradation of amorphous and crystalline regions in film-blown poly(ε-caprolactone)

The surface erosion of films of poly(epsilon-caprolactone) (PCL) in compost, in anaerobic sewage sludge and by Aspergillus fumigatus was compared with chemical hydrolysis (23 and 50 degrees C). Biodegraded samples displayed grooves or cracks arranged in parallel, whereas samples exposed to an abiotic environment showed no surface changes. Differences in micro-flora together with the initial morphology of the sample resulted in different mechanisms of erosion. The degradation in compost resulted in parallel grooves or cracks, while A. fumigatus produced a spherulitic erosion pattern. A preferential degradation in the amorphous parts produced low-molar mass fractions with lengths corresponding to one, two or several times the thickness of the crystal lamellae. (C) 1999 Elsevier Science Ltd. All rights reserved.