The material. Polychloroprenes (Neoprene, CR), the materials of wetsuits, are the leading nontire synthetic rubbers. First synthesized in 1930, they are made by a condensation polymerization of the monomer 2-chloro-1,3 butadiene. The properties can by modified by copolymerization with sulfur, with other chloro-butadienes and by blending with other polymers to give a wide range of properties. Polychloroprenes are characterized by high chemical stability and resistance to water, oil, gasoline, and UV radiation.
Composition
(CH2-CCl-CH2-CH2)n
General properties
|
Density |
1230 |
– 1250 |
kg/m3 |
|
Price |
*5.33 |
– 5.86 |
USD/kg |
|
Mechanical properties Young’s modulus |
7e-4 |
– 0.002 |
GPa |
|
Yield strength (elastic limit) |
3.4 |
– 24 |
MPa |
|
Tensile strength |
3.4 |
– 24 |
MPa |
|
Compressive strength |
3.72 |
– 28.8 |
MPa |
|
Elongation |
100 |
– 800 |
% |
|
Fatigue strength at 107 cycles |
*1.53 |
– 12 |
MPa |
|
Fracture toughness |
*0.1 |
– 0.3 |
MPa. m1/2 |
|
Thermal properties Glass temperature |
-48.2 |
– -43.2 |
°C |
|
Maximum service temperature |
102 |
– 112 |
°C |
|
Thermal conductor or insulator? |
Good insulator |
||
|
Thermal conductivity |
0.1 |
– 0.12 |
W/m. K |
|
Specific heat capacity |
*2000 |
– 2200 |
J/kg. K |
|
Thermal expansion coefficient |
575 |
– 610 |
p, strain/°C |
|
Electrical properties Electrical conductor or insulator? |
Good insulator |
|
|
Electrical resistivity |
1 X 1019 – 1 X 1023 |
pnhm. cm |
|
Dielectric constant |
6.7 – 8 |
|
|
Dissipation factor |
*1 X 10-4 – 0.001 |
|
|
Dielectric strength |
15.8 – 23.6 106 |
V/m |
Neoprene gives wetsuits flexibility and stretch.
Ecoproperties: material
Embodied energy, primary production CO2 footprint, primary production Water usage
Ecoproperties: processing
Polymer molding energy Polymer molding CO2
Recycling
Recycle fraction in current supply
Typical uses. Brake seals, diaphragms, hoses and o-rings, tracked-vehicle pads, footwear, wetsuits.
