EPS-type Thioplast are epoxy-terminated, low viscosity polysulfides. The introduction of epoxy-termination into the polysulfide structure results in the formation of a unique polymer which combines the excellent properties of Akzo Nobel polysulfides with the most desirable features of epoxy-resin systems.
These are:
· Excellent adhesion to most surfaces
· Chemical resistance to many dilute acids, alkalis and solvents
· Mechanical stability and durability
· High speed of curing at ambient temperatures.
Depending on the field of application, THIOPLASTTM EPS can either be used alone or in combination with conventional aromatic glycidylethers and other epoxies.
Chemistry of THIOPLAST™ EPS
The chemical structure is dominated by the polysulfide backbone – SS-, formal units and the highly reactive epoxy endgroups. Depending on the type of reaction, the spacer R’ varies.
| R - polysulfide structure |
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| –(CH2CH2OCH2OCH2CH2-SS)n- CH2CH2OCH2OCH2CH2- |
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| n = 8 – 20 |
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| R‘ – aliphatic or cycloaliphatic |
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All THIOPLAST™ polysulfides can be used as a polymer backbone. This allows a great variability in viscosity and the degree of pre-branching of the resulting EPS types.
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EPS 15 |
EPS 25 |
EPS 70 |
EPS 350 |
| Structure |
Aliphatic type |
Aliphatic type |
Aromatic type |
Aromatic type |
| Branching in mol-% |
2 |
2 |
0 |
0 |
| Viscosity in Pa*s (20°C) |
9-15 |
2-3 |
5-10 |
30-40 |
| Oxygen cont. in wt-% |
1.0-1.5 |
2.1-2.9 |
4.6-5.0 |
4.5-5.5 |
| Epoxy equivalent in g/equiv. |
1100-1500 |
500-600 |
280-350 |
300-370 |
| Density in g/cccm (20°C) |
1.27 |
1.27 |
1.20 |
1.23 |
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| For detailed technical information and test formulations, please see our brochures and data sheets Downloads. |