Fig. 3: Effect of Tg and Mn on polymer degradation.

a Abiotic processes for Tg values < 0 °C, b biotic processes and photo-initiated oxidation for Tg values < 0 °C, c abiotic processes for Tg values > 0 °C, d biotic processes and photo-initiated oxidation for Tg values > 0 °C. Degradation categories depicted on 5-tier scale and shown by size of data point and color (yellow > light green > green > blue > purple).