Figure 5.

Provisional biodegradability in PLA anaerobic biodegradation test.

The test vessels were incubated at 35 °C (a) and 55 °C (b). ⋄; cellulose 10g, Δ,□; PLA 10g. The biodegradabilities at each point were calculated as ((ΣV(s) – ΣV(b))/V(max)) × 100. The gas volumes from blank vessel were 0.03 (L) in 77 days (a) and 0.79 (L) in 73 days (b), measured at the end of the test. The gas volume from the blank vessel at each measuring point is calculated as ((incubation time)/77) × 0.03 (a), ((incubation time)/73) × 0.79 (b). The gas volume from the blank vessel at each measuring point is assumed to be the values when the volume from the blank vessel at the end of the test is proportionally divided by the incubation time.