Apr 30 2003
Background
Polyethersulphone is an amorphous, transparent and pale amber high performance thermoplastic with the characteristics common to this group - see polyetheretherketone (PEEK).
Like Polyetherimide (PEI), its properties are somewhat inferior to PEEK and it is less expensive. Polyethersulphone has a slightly higher temperature resistance than PEI (but less than PEEK) and is the most temperature resistant transparent commercially available thermoplastic.
It has a relatively high water absorption and, in common with many other plastics, drying is essential before e.g. thermoforming. Polyethersulphone has poor fatigue characteristics and is prone to environmental stress cracking but has good long term thermal ageing resistance and reasonable radiation resistance. Its chemical resistance is not as wide as PEEK's; hence stable solutions can be made if solvents are correctly chosen.
Industrial Applications
Applications of Polyethersulphone include electrical and electronic components, medical equipment that needs repeated sterilisation and photographic accessories.
Key Properties
The key properties of Polyethersulphone are tabulated below.
Table 1. Key properties
| Chemical Resistance |
| Acids - Concentrated |
Fair |
| Acids - dilute |
Good |
| Alcohols |
Good |
| Alkalis |
Good |
| Aromatic Hydrocarbons |
Fair |
| Greases and Oils |
Good |
| Halogens |
Good |
| Ketones |
Poor |
| Electrical Properties |
| Dielectric constant @ 1 MHz |
3.7 |
| Dielectric strength ( kV.mm-1 ) |
16 |
| Dissipation factor @ 1 MHz |
0.003 |
| Volume resistivity ( Ohm.cm ) |
1017 |
| Mechanical Properties |
| Abrasive resistance - ASTM D1044 ( mg/1000 cycles ) |
6 |
| Elongation at break ( % ) |
40-80 |
| Hardness - Rockwell |
M88 |
| Izod impact strength ( J.m-1 ) |
85 |
| Poisson's ratio |
0.4 |
| Tensile modulus ( GPa ) |
2.4-2.6 |
| Tensile strength ( MPa ) |
70-95 |
| Physical Properties |
| Density ( g.cm-3 ) |
1.37 |
| Flammability |
V-0 @ 0.4 mm |
| Limiting oxygen index ( % ) |
34-41 |
| Radiation resistance - Alpha |
Good |
| Refractive index |
1.65 |
| Resistance to Ultra-violet |
Fair |
| Water absorption - equilibrium ( % ) |
2.2 |
| Water absorption - over 24 hours ( % ) |
0.4-1 |
| Thermal Properties |
| Coefficient of thermal expansion ( x10-6 K-1 ) |
55 |
| Heat-deflection temperature - 0.45 MPa (°C ) |
>260 |
| Heat-deflection temperature - 1.8 MPa (°C ) |
203 |
| Lower working temperature (°C ) |
-110 |
| Thermal conductivity ( W.m-1.K-1 ) |
0.13-0.18 @ 23 |
| Upper working temperature (°C ) |
180-220 |
| Properties Polyethersulphone Film |
| Property |
|
Value |
| Dielectric Constant @ 1 MHz |
|
3.7 |
| Dielectric Strength @ 25 µm thick |
kV.mm-1 |
232 |
| Dissipation Factor @ 1 MHz |
|
0.012 |
| Elongation at Break |
% |
20-150 |
| Flammability |
|
VTM-0 @ 25 µm |
| Heat-sealing Temperature |
°C |
259-287 |
| Initial Tear Strength |
g.µm-1 |
7.5-16.9 |
| Permeability to Carbon Dioxide @ 25 °C |
x10-13 cm3.cm.cm-2.s-1.Pa-1 |
1.8 |
| Permeability to Oxygen @ 25 °C |
x10-13 cm3.cm.cm-2.s-1.Pa-1 |
0.4 |
| Permeability to Water @ 25 °C |
x10-13 cm3. cm.cm-2.s-1.Pa-1 |
75 |
| Specific Heat |
kJ.kg-1.K-1 |
1.1 |
About Goodfellow
Goodfellow supplies metals, ceramics and other materials to meet the research, development and specialist production requirements of science and industry worldwide.
.gif)
Source: Goodfellow
For more information on this source please visit Goodfellow.