What is a SEBS polymer

TPE - SEBS

These styrene block polymers have a 3-block structure, consisting of two styrene end blocks (hard component) and a soft middle block (ethylene-butylene).
Can be processed on normal thermoplastic machines (the processing of SEBS is roughly similar to that of PP with a medium to high melt index)

Wide hardness range from Shore A4 to A95

Molecular structure
SEBS (styrene-ethylene-butylene-styrene)
features
The mechan. Properties allow areas of use at long-term temperatures from -40 ° C to 120 ° C. Very good compression and tensile deformation values ​​at room temperature, at 70 ° C and sometimes even 100 ° C, depending on the type. Excellent dynamic fatigue strength.
Flammability
Standard types HB according to UL 94 (burning speed <100mm / min)
Resistances
excellent weather and ozone resistance. Resistant to water, acids and bases. Hydrocarbons cause structural changes (but short contacts are possible).
Colored standard types have good UV resistance - extra UV stabilization on request.
Connections with other thermoplastics
By coextrusion, over-u. Injections result in numerous hard-soft combinations with polyolefin plastics (PP, PE, PS)

 

Processing instructions

Processing is usually carried out on normal thermoplastic machines

Pre-drying: not applicable (if stored properly), as it is not hygroscopic.

 

Injection molding

Temperature picture (low temp. For soft types / higher temp. For harder types)

Rear cylinder zone: 160 - 180 ° C
Front cylinder zone: 170 - 190 ° C
Nozzle: 170 - 190 ° C
Mass: 170 - 210 ° C
Tool: 30 - 60 ° C

 

Extrusion

PVC or PE screws with L / D> 20 are preferred.
Compression ratio: 2.5 :! up to 3.5: 1
Temperature picture (low temp. For soft types / higher temp. For harder types)
Feed zone: 170 - 200 ° C
Transition zone: 175 - 205 ° C
Dosing zone: 180 - 210 ° C
Front area: 180 - 200 ° C
Nozzle: 185 - 215 ° C
Mass: 170 - 210 ° C