HEAT CURED SILICONE RUBBER IOTA HCR 1940 U
Description: IOTA HCR 1940 U is a silicone master-batch, heat curing after the addition of a vulcanizing agent (chosen according to the processing method).
Applications: IOTA HCR 1940 U is recommended for moulding, has good compromise of mechanical properties.
Special properties:
Good mechanical properties;
Good appearance;
Good heat stability, up to 200°C;
Not easy to structured after long-term storage;
No need to post-cure or post-cure time is short;
Wide possibilities for blending with other master batch.
Characteristics
Type (in accordance with GB/T 5576-1997) ……………………………… VMQ
Density at 25°C, g/cm3, approx……………………………………………… 1.12
Natural color……………………………………………………………………… translucent
Properties after working:
1) After addition of 1.25% Di(2,4-dichlorobenzoyl) peroxide (at 50%), and vulcanization for 8min at 115℃.
2) After addition of 1.1% 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane (at 45%), and vulcanization for 10 minutes at 175℃.
1. Mechanical property:
1.1 Properties before post-cure 1) 2)
Shore A hardness, approx……………………………………… 47 41
Tensile strength, MPa, approx…………………………………… 9.3 9.9
Elongation at break, %, approx………………………………… 443 594
Modulus at 100% elongation, MPa, approx…………………… 1.26 0.83
Tear strength, (ASTM D 624 Die B) kN/m, approx………………. 16 17
Rebound resilience, %, approx…………………………………… 67 63
Linear shrinkage, %, approx……………………………………… 1.4 3.7
1.2 properties after post-cure for 4 hours at 200°C
Shore A hardness, approx………………………………………… 45 42
Tensile strength, MPa, approx…………………………………….. 8.0 9.1
Elongation at break, %, approx………………………………… 397 527
Modulus at 100% elongation, MPa, approx………………… 1.26 0.89
Tear strength (ASTM D 624 Die B)，kN/m, approx………… 12.4 14.6
Rebound resilience, %, approx…………………………………… - 26.5
Compression set , (22 h/177℃/25%) %, approx………………… 65 60
Linear shrinkage, %, approx………………………………………… 2.0 4.0
2. Thermal stability
Properties after post-cure for 3 days at 225°C
Shore A hardness, approx…………………………………………… 35 30
Tensile strength, MPa, approx…………………………………….. 7.0 6.3
Elongation at break, %, approx…………………………………… 451 534
Packaging: IOTA HCR 1940 U is delivered in 20 kg carton boxes.
Storage and shelf life: IOTAHCR 1940 U may be stored in its original unopened packaging at a temperature below 40°C for up to 6 months from the date of manufacture marked clearly on the packaging.
Past this date, IOTA no longer guarantees that the product meets the sales specifications.
