The material. Ethylene-Vinyl-Acetate elastomers (EVA) are built around polyethylene. They are soft, flexible, and tough and retain these properties down to -60°C and have good barrier properties as well as FDA approval for direct food contact. EVA can be processed by most normal thermoplastic processes: co-extrusion for films, blow molding, rotational molding, injection molding, and transfer molding.
Composition
(CH2)n-(CH2-CHR)m
General properties
|
Density |
945 |
– 955 |
kg/m3 |
|
Price |
*2.1 |
– 2.31 |
USD/kg |
|
Mechanical properties Young’s modulus |
0.01 |
– 0.04 |
GPa |
|
Yield strength (elastic limit) |
12 |
– 18 |
MPa |
|
Tensile strength |
16 |
– 20 |
MPa |
|
Compressive strength |
13.2 |
– 19.8 |
MPa |
|
Elongation |
730 |
– 770 |
% |
|
Fatigue strength at 107 cycles |
*12 |
– 12.8 |
MPa |
|
Fracture toughness |
*0.5 |
– 0.7 |
MPa. m1/2 |
|
Thermal properties Glass temperature |
* -73.2 |
– -23.2 |
°C |
|
Maximum service temperature |
46.9 |
– 51.9 |
°C |
|
Thermal conductor or insulator? |
Good insulator |
||
|
Thermal conductivity |
0.3 |
– 0.4 |
W/m. K |
|
Specific heat capacity |
*2000 |
– 2200 |
J/kg. K |
|
Thermal expansion coefficient |
160 |
– 190 |
p, strain/°C |
|
Electrical properties Electrical conductor or insulator? |
Good insulator |
||
|
Electrical resistivity |
*3.1 X 1021 – |
1 X 1022 |
pnhm. cm |
|
Dielectric constant |
2.9 – |
2.95 |
|
|
Dissipation factor |
0.005 – |
0.022 |
|
|
Dielectric strength |
26.5 – |
27 106 |
V/m |
EVA is available in pastel or deep hues; it has good clarity and gloss. It has good barrier properties, little or no odor, and UV resistance.
|
Ecoproperties: material
Ecoproperties: processing Polymer molding energy Polymer molding CO2 |
7.4 – 8.84 MJ/kg
0.592 – 0.707 kg/kg
Recycling
Embodied energy, recycling CO2 footprint, recycling Recycle fraction in current supply
Typical uses. Medical tubes, milk packaging, beer dispensing equipment, bags, shrink film, deep freeze bags, co-extruded and laminated film, closures, ice trays, gaskets, gloves, cable insulation, inflatable parts, running shoes.
