Table – 2.
Various properties of polymers used in the manufacturing of the disposable facemasks.
| Property | PP [11] | LDPE [12] | HDPE [13] |
|---|---|---|---|
| Density (g/cm3) | 1.04–1.06 | 0.915–0.92 | 0.94–0.96 |
| Elastic modulus (GPa) | 1.5–3 | 0.2–0.48 | 0.6–1.4 |
| Coefficient of thermal expansion (1/K at 20 °C) | 6 × 10−5 – 1 × 10−4 | 23 × 10−5 – 25 × 10−5 | 12 × 10−5 – 20 × 10−5 |
| Max. Service temperature, short | 140 | – | – |
| Melting point (°C) | 160–168 | 105–120 | 126–135 |
| Specific heat capacity (J/kg. K at 20 °C) | 1,520 | 2,100–2500 | 2,100–2,700 |
| Thermal conductivity (W/m.K at 20 °C) | 0.41 | 0.32–0.4 | 0.38–0.51 |
| Flammability | UL 94 H B | UL 94 H B | UL 94 H B |
| Dielectric constant (at 20 °C) | 2.8 | 2.2–2.3 | 2.3–2.5 |
| Electrical resistivity (Ω.m at 20 °C) | 1013–1014 | 1015 | 1015 |