ACTIVE ZINC OXIDE (ACTIVATED / TRANSPARENT)
Organic accelerators used in rubber compounding are almost always dependant on the presence of activators. Zinc Oxide is the most important of such activators.
FEATURES:
- They are very small particle sizes zinc-oxide active & transparent grades cause very powerful activation of the cure. Depending on the type and amount of accelerator present they can considerably delay the onset of cure without simultaneously extending the total curing time.
- They have stronger activating effect, the amount of this substance needed for the same modulus is lesser as compared to ordinary Zinc Oxide.
- Unlike ordinary Zinc-Oxide, our grade is compatible with the production of transparent goods as it does not impair the transparency of the vulcanizates when added in small and moderately large amounts.
- They cause no changes in the colour of the vulcanizates. They reduce yellowing in white and light coloured goods which are exposed to strong light.
- As they do not have pigmenting properties, they do not influence effect of colour pigments provided they are not too heavily loaded.
- Due to exceptionally low lead compound contents they are particularly suitable for vulcanizates intended to be practically free from heavy metals.
- They do not boom.
APPLICATIONS:
- Can be used as activators in : 1. sulphur cures 2. peroxide cures (often) 3. sulphurless metallic-oxide cures. Used as crosslinking agent for lattices with reactive groups and for CR.
- Suitable for following types of rubber-NR, IR, BR, SBR, NBR, IIR, CR, EPDM, CSM.
- Transparent goods i.e. injection caps, condoms, gloves, lab. appartus.
- Rubber foam.
- Highly elastic vulcanizates (spring components).
USAGE:
- Owing to the fineness of particles, Active Zinc Oxide is very easy to incorporate and disperse well.
- They raise the viscosity of the mix. Large additions stiffen the mix considerably.
- As their proportion is increased the thermal conductivity of rubber mixes is raised which isan advantage in hot air curing.
- In large proportions, zinc-oxide active behaves like reinforcing filler. It gives vulcanizates highgh tensile strength and rebound resilience with a simultaneous increase in hardness. It also imparts resistance to ageing and protection against flex-cracking
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Active Zinc Oxide RT-70 |
TYPICAL PHYSIOCHEMICAL PROPERTIES |
Property |
Unit |
Value |
Surface Area (BET) |
m²/gm |
22-26 |
Bulk Density* |
gm/cc |
0.35-0.45 |
Oil Absorption |
% |
110-130 |
pH (2% acq. Solution) |
% |
7.2-8.8 |
ZnO |
% |
72±4 |
Pb, Cu, Ni, Mn, Cd |
ppm max.(total) |
20 |
Moisture ( at 90°C) |
% |
<2.0 |
Residue on 300 mesh |
% |
<0.8 |
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