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Advanced Elastomer Systems Santoprene® 251-92 Thermoplastic Rubber

Subcategory: Elastomer, TPE; Polymer; Thermoplastic

Material Notes:
A colorable thermoplastic flame retardant elastomer with good fluid resistance, formulated to replace thermoset elastomers such as EPDM, polychloroprene, and chlorosulfonated polyethylene. It can be processed using injection molding, extrusion, blow molding or other melt processing techniques.

Key Features: Dielectric constant 2.43, dielectric strength at 3.17 mm (125 mil), 19.6 kV/mm (500 v/mil); UL Yellow Card listed, UL 94 flame rating V-O; Limiting oxygen index, 25%; Excellent flex fatigue resistance; Excellent ozone resistance

Additional processing comments: This thermoplastic rubber is a shear-dependent material that can be processed on conventional thermoplastic equipment for injection molding, extrusion, or blow molding. For extrusion, a general purpose screw with a compression ratio of 2.5 to 3.0 is recommended. Material can be recycled. SANTOPRENE rubber is incompatible with acetal and PVC.

Values below are for injection molded plaques, side gated, 82.6 mm x 117.5 mm x 3.0 mm. Tensile properties measured across flow. Data provided by Advanced Elastomer Systems.

Physical Properties	Metric	English	Comments
Density	1.22 g/cc	0.0441 lb/in³	TPE-0105 (ASTM D792)
Mechanical Properties
Hardness, Shore A	92	92	5 Second; TPE-0169 (ASTM D 2240)
Tensile Strength, Ultimate	12.4 MPa	1800 psi	TPE-0153 (ASTM D 412)
Elongation at Break	530 %	530 %	TPE-0153 (ASTM D 412)
100% Modulus	0.006 GPa	0.87 ksi	TPE-0153 (ASTM D 412)
Tear Strength	44.3 kN/m	253 pli	44.3 kN/m at 23°C. Value at 100°C is 18.4 kN/m. TPE-0056 (ASTM D 624)
Compression Set	35 %	35 %	23°C, 168 hrs.; TPE-0016 (ASTM D 412)
Compression Set, Elevated Temperature	62 %	62 %	100°C, 168 hrs.; TPE-0016 (ASTM D 412)
Tensile Set	21 %	21 %	23°C, 168 hrs.; TPE-0053 (ASTM D 412)
Electrical Properties
Dielectric Constant	2.43	2.43	Frequency not specified
Dielectric Strength	19.6 kV/mm	498 kV/in	at 3.17 mm (0.125 in)
Thermal Properties
Brittleness Temperature	Max -55 °C	Max -67 °F	TPE-0089 (ASTM D 746)
Flammability, UL94	HB	HB
Oxygen Index	25 %	25 %
Processing Properties
Processing Temperature	177 - 232 °C	351 - 450 °F
Drying Temperature	82 °C	180 °F	Desiccant drying for 3 hours recommended
Dry Time	3 hour	3 hour