Polychloroprene (Neoprene, CR)

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.