## 3 Results
### Biodegradation Test  
Figure 6 presents the percentage of mass loss over immersion days from the biodegradation rate test of miniplate samples with varied injection molding temperatures, grouped by sample compositions. In Figure 6a, the degradation rate of miniplates with the addition of 10% PEG plasticizer to the PLA matrix without sago starch blend (SPLA0P10) is depicted. The mass loss percentage at 7 days after treatment was 1.04% at 150 \({}^{\circ}\)C, 1.02% at 160 \({}^{\circ}\)C, 1.84% at 170 \({}^{\circ}\)C and 2.54% at 180 \({}^{\circ}\)C. Degradation slowed down on the 14 th day, with no  
Figure 5: Stress–strain curves of miniplate samples with varied injection molding temperatures obtained from bending testing, grouped by sample compositions: (**a**) SPLA0P10, (**b**) SPLA20P0, (**c**) SPLA20P10 and (**d**) SPLA20P20. degradation observed at 150 \({}^{\circ}\)C and 160 \({}^{\circ}\)C. At 170 \({}^{\circ}\)C, there was a mass loss of 0.21% and at 180 \({}^{\circ}\)C, the highest mass loss percentage was recorded at 0.62%. By the 21 st day, mass loss at 150 \({}^{\circ}\)C increased to 2.67%, at 160 \({}^{\circ}\)C there was a mass loss of 0.82%, at 170 \({}^{\circ}\)C it was 0.42% and at 180 \({}^{\circ}\)C of 0.83%. Figure 6b illustrates how changes in injection temperature impacted the mass loss percentage of SPLA20P0 miniplates derived from PLA/starch mixtures. The mass loss percentage after 7 days of treatment was 0.61% at 150 \({}^{\circ}\)C, 1.58% at 160 \({}^{\circ}\)C, 1.2% at 170 \({}^{\circ}\)C and 3.78% at 180 \({}^{\circ}\)C. The highest mass loss percentage was observed at 180 \({}^{\circ}\)C, while the lowest was at 150 \({}^{\circ}\)C. On the 14 th day, degradation slowed down, with no degradation observed at 150 \({}^{\circ}\)C and 170 \({}^{\circ}\)C. At 160 \({}^{\circ}\)C, there was a mass loss of 1.01%; at 180 \({}^{\circ}\)C, the highest mass loss percentage was recorded at 3.35%. By the 21 st day, mass loss at 150 \({}^{\circ}\)C increased to 2.26%, at 160 \({}^{\circ}\)C there was a mass loss of 0.82%, at 170 \({}^{\circ}\)C it was 1.21% and at 180 \({}^{\circ}\)C it reached 2.17%. The mass loss percentage of miniplates SPLA0P10 was slower than that of SPLA20P0, suggesting that the presence of starch impacted the mass loss percentage. Figure 6: Average mass loss percentage over immersion days during biodegradation rate test of miniplate samples with varied injection molding temperatures grouped by sample compositions: (a) SPLA0P10, (b) SPLA20P0, (c) SPLA20P10 and (d) SPLA20P20 (\(n=3\)). Figure 6c illustrates the mass loss percentage of miniplates with the addition of 10% PEG plasticizer to the PLA/sago starch mixture (SPLA20P10). Similar to SPLA20P0 and SPLA0P10, changes in injection temperature affected the miniplate's mass loss percentage. The mass loss percentage at 180 \({}^{\circ}\)C was higher compared to lower temperatures, while at 150 \({}^{\circ}\)C and 160 \({}^{\circ}\)C, it remained uniform up to 7 days of treatment. The mass loss percentage at 7 days after treatment was 3.97% at 150 \({}^{\circ}\)C, 4.03% at 160 \({}^{\circ}\)C, 2.73% at 170 \({}^{\circ}\)C and 6.55% at 180 \({}^{\circ}\)C. On the 14 th day, mass loss slowed down, with mass loss of 0.63% at 150 \({}^{\circ}\)C, 1.67% at 160 \({}^{\circ}\)C, 2.16% at 170 \({}^{\circ}\)C and 2.12% at 180 \({}^{\circ}\)C. By the 21 st day, mass loss at 150 \({}^{\circ}\)C increased to 2.52%, at 160 \({}^{\circ}\)C there was a mass loss of 1.28%, at 170 \({}^{\circ}\)C it was 0.66% and at 180 \({}^{\circ}\)C reached 2.18%. The mass loss percentage increased with the increase in injection temperature. Figure 6d illustrates the effect of adding 20% PEG plasticizer to the PLA/sago starch mixture on the mass loss percentage (SPLA20P20). Changes in injection temperature did not seem to affect the mass loss percentage, although at 150 \({}^{\circ}\)C, it had the lowest mass loss percentage compared to other temperatures.