What are the physical and mechanical properties of Parylene?
Parylene是一种高分子涂层（约50KD），无需经过传统液挤压铸造等工艺，熔点高，结晶度高，涂层光学透明，自润滑性能好，具有良好的物理和机械性能，见下表。
| performance | Parylene N | Parylen e C | ParyleneF4 | ParyleneF8 | Epoxy resin ER | Silicone resin SR | Polyurethane UR | Polyacrylate AR | |
| Young’s modulus Mpa | 2400 | 3200 | 2800 | 2600 | 2400 | 720 | 80-800 | 480 | |
| Tensile strength Mpa | 45 | 70 | 54 | 55 | 28-91 | 5.6-7 | 1.13-70 | 32-77 | |
| Fracture extension% | 20-250 | 20-200 | 10-50 | 10 | 3-6 | 100 | 100-1000 | 3-85 | |
| Yield extension% | 2.9 | 2.5 | 2.5 | 2 | |||||
| Linear expansion coefficient 25 ℃ 10 ⁻⁵/℃ | 6.9 | 3.5 | – | – | 4.5-6.5 | 25-30 | 10-20 | 0.5-15 | |
| Thermal conductivity of 110 ⁴ cal/cm ⋅ ° C | 3 | 2 | – | – | 4-5 | 3.5-7.5 | 5 | 3-6 | |
| melting point | 420 | 290 | – | – | Solidify | Solidify | ~170/ Solidify | – | |
| Specific heat 20 ℃ · cal/g · ℃ | 0.2 | 0.17 | 0.25 | 0.42 | |||||
| Density g/cm3 | 1.1 | 1.29 | 1.6 | 1.5 | 1.11-1.40 | 1.05-1.23 | 1.10-2.50 | 1.19 | |
| Refractive index nD23 | 1.661 | 1.639 | 1.58 | 1.559 | 1.55-1.61 | 1.43 | 1.50-1.60 | 1.48 | |
| hardness | R85 | R80 | R115 | R120 | M80-110 | 40-45AShore | 10A-25DShore | H-2H | |
| coefficient of friction | static | 0.25 | 0.29 | 0.35 | 0.15 | 1 | |||
| dynamic | 0.25 | 0.29 | 0.13 | 1 | |||||
