HCR 175 U is a silicone master batch, vulcanizing under heat after addition of a vulcanizing agent (chosen according to the vulcanizing process).

Details

HEAT CURED SILICONE RUBBER  HCR 175 U

Description： HCR 175 U is a silicone master batch, vulcanizing under heat after addition of a vulcanizing agent (chosen according to the vulcanizing process).

Applications：Moulding, injection, extrusion of articles with good mechanical properties.

Special properties：

Very slight replastification after prolonged storage

Easy to process

No post-cure or slight post-cure

Good mechanical properties

Good heat stability, up to 200℃

Transparency

Wide possibility of reloading and blending

Characteristics：

Type(in accordance with GB/T 5576/1997) ………………………………………… VMQ

Density at 25℃, g/cm3, approx………………………………………………………… 1.18

Natural color…………………………………………………………Colorless, transparent

Properties after working:

(1) After addition of 1.25% 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……………………………….       69         67

Tensile strength, MPa, approx………………………………    9.8        9.7

Elongation at break, %, approx……………………………    270        320

Modulus at 100% elongatioin, MPa, approx ………………  3.6        2.8

Tear strength, kN/m, approx…………………………………   21         24

Rebound resilience, %, approx…………………………………  54        46

Linear shrinkage, %, approx. …………………………………    2.6       4.2

1.2 Properties after post-cure for 4 hours at 200℃    

Shore A hardness, approx…………………………………….    75        74

Tensile strength, MPa, approx…………………………………   9.3       9.4

Elongation at break, %, approx……………………………     260       290

Modulus at 100% elongatioin, MPa, approx ……………     3.4        3.1

Tear strength, kN/m, approx…………………………………     21        23

Compression set (22h/177℃/25%), %, approx……………     37        29

Rebound resilience, %, approx…………………………………    45      41

Linear shrinkage, %, approx……………………………………     2.6      4.2

2. Heat stability

2.1 Properties after ageing 10 days at 200°C

Shore A hardness, approx……………………………………      78       80

Tensile strength, MPa, approx…………………………………    7.3       7.2

Elongation at break, %, approx…………………………………   200      190

Packaging:  HCR 175U is delivered in 20 kg carton boxes.

Storage and shelf life:  HCR 175U 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,  no longer guarantees that the product meets the sales specifications.