HEAT CURED SILICONE RUBBER IOTA HCR 345 U
Description:IOTA HCR 345 U is a very transparent silicone heat-curing elastomer which vulcanizes after the addition of a vulcanizing agent selected in accordance with the transformation process.
Applications:Molding and extrusion of transparent parts with high mechanical properties.
Special properties:
Only slight freshening required
Short post cure
High transparency
High mechanical properties. Offers a good compromise between tear strength and ompression set
Characteristics:
Type(in accordance with GB/T 5576/1997) ………………………………………… VMQ
Density at 25℃, g/cm3, approx………………………………………………………… 1.10
Natural color…………………………………………………………Colorless, transparent
Properties after working:
(1) After addition of 1.1% 2,4-dichloro-benzoyl peroxide (at 50%), and vulcanization for 8min at 115℃
(2) After addition of 1.0% 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane at 45%, and vulcanization for 10 minutes at 170℃
1. Mechanical properties
1.1 Properties without post-cure (1) (2)
Shore A hardness, approx………………………………. 41 43
Tensile strength, MPa, approx……………………………… 7.3 7.8
Elongation at break, %, approx…………………………… 560 600
Modulus at 100% elongatioin, MPa, approx ……… 1.1 1.3
Tear strength, kN/m, approx………………………………… 36 38
Rebound resilience, %, approx………………………………… 45 44
Linear shrinkage, %, approx. …………………………………… 2.3 3.5
1.2 Properties after post-cure for 4 hours at 200℃
Shore A hardness, approx……………………………………. 45 48
Tensile strength, MPa, approx……………………………… 7.2 7.7
Elongation at break, %, approx…………………………… 460 490
Modulus at 100% elongatioin, MPa, approx ……… 1.2 1.5
Tear strength, kN/m, approx………………………………… 31 37
Compression set (22h/177℃/25%), %, approx……… 42 26
Rebound resilience, %, approx……………………………… 46 45
Linear shrinkage, %, approx. ………………………………… 3.2 3.4
2. Heat stability
2.1 Properties after heat-ageing 10 days at 200°C
Shore A hardness, approx…………………………………… 47 54
Tensile strength, MPa, approx……………………………… 7.0 7.1
Elongation at break, %, approx……………………………… 390 320
Packaging: IOTA HCR 345 U is delivered in 20 kg carton boxes.
Storage and shelf life: IOTA HCR 345 U may be stored in its original unopened packaging at a temperature below 40℃ for up to 18 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.