When we talk about platinum or peroxide curing in the silicone world, curing is when the silicone rubber is chemically cross-linked by means of the addition of a peroxide or platinum curing agent. The curing agents differ chemically to give the end product, in this case silicone, different properties. Here we look at the positives and negatives of each system to make it clearer when deciding on what silicone material you require for your application.
Peroxide Cured Silicone
- Easier to process – needs less temperature to cure the silicone
- Once mixed, a peroxide cured silicone compound has a vastly superior shelf life so can be stored and used for longer
- Generally cheaper to buy the raw ingredients so more competitive prices
- Tried and tested systems and the industry standard
- Sheets and tubing not as clear as platinum cured silicone. Peroxide is more translucent in appearance rather than transparent
- Needs talc or an introduction of a liner to prevent the silicone sticking to itself especially when manufacturing silicone sheeting
Platinum Cured Silicone
- Sheets and tubes are clearer so more visibility through the material
- Can be run talc free
- Generally physical properties are better especially tensile strength and tear strength
- Viewed as being the cleaner silicone out of the two which is why it is favoured in the Food, Beverage and Medical sectors
- More expensive than peroxide which can be prohibitive if cost is an issue
- Harder to process – needs relatively high temperatures to cure
- Short shelf life – once mixed the compound has a very short shelf life and so this usually leads to waste such as head set ups being scrapped etc
At Silicone Engineering we offer both peroxide and platinum grades of silicone. The majority of silicone we make is peroxide cured silicone however for applications within the Food, Beverage and Medical sectors, we also offer platinum grades which are favoured in these sectors.
Overall, both curing systems produce quality silicone materials if manufactured to high standards and specifications. Both have positives and negatives and which one you choose should be in relation to the application and where the silicone will end up.