Table 1.
PLA mechanical properties compared to those of most common polymers used in commodity applications [Copyright ©(2011) Wiley and Sons; used with permission from Liu and Zhang (2011)].
| PLA | PET | PS | HIPS | PP | |
|---|---|---|---|---|---|
| Tg (°C) | 55–65 | 75 | 105 | – | 10 |
| Tensile strength at break (MPa) | 53 | 54 | 45 | 23 | 31 |
| Tensile modulus (GPa) | 3.4 | 2.8 | 2.9 | 2.1 | 0.9 |
| Elongation at break (%) | 6 | 130 | 7 | 45 | 120 |
| Notched Izod impact strength (J/m) | 13 | 59 | 27 | 123 | 27 (i-PP) |
| Gardner impact (J) | 0.06 | 0.32 | 0.51 | 11.30 | 0.79 |
| Cost ($/lb)a | 1–1.5 | 0.70–0.72 | 0.99–1.01 | 1.01–1.03 | 1.15–1.17 |
PET, Poly(ethylene terephthalate); PS, Polystyrene; HIPS, High-impact polystyrene; PP, Polypropylene; i-PP, Isotactic polypropylene homopolymer.
a
Cost cited from “Plastic News”, March 31, 2011 except PLA resin.