Liquid silicone rubber (LSR) molds and tubing are becoming increasingly popular in manufacturing and a number of other industrial processes. Silicone molds and tubing are distinguished by the type of curing process they employ. Peroxide-cured silicone uses a process called free radical curing, whereas platinum-cured silicone uses addition curing.
A detailed discussion of the chemical differences between these two processes is beyond the scope of this page. Instead, we will look specifically at platinum-cured silicone, its properties and potential applications. Read on to learn more.
Platinum-Cured Silicone: Pros and Cons
No one type of material is right for every process. By far the biggest benefit to using platinum-cured silicone molds is that the platinum curing process produces no peroxide residues, so the risk of mold fouling is greatly decreased. This reduces down time, which improves your overall productivity.
Other advantages of platinum curing may include improved product clarity and consistency, and potentially somewhat better elongation, tensile strength, and tear strength compared to peroxide-cured materials.
However, platinum-cured silicone has its downsides, too. Platinum curing tends to be more expensive, which drives up your initial operating costs (though this initial expense may be offset over time by gains in productivity). Platinum is also sensitive to contamination, and exposure to latex, sulfur, tin-cure silicone and other products will inhibit its cure. With care, however, it’s possible to avoid these issues.
Applications and Benefits
Platinum-cured silicone’s unique properties lend it to a wide range of potential applications, including:
- Any processes in which the ability to withstand temperature extremes, radiation, corona, ozone exposure, moisture, and/or steam is desired. High purity platinum-cured silicone is often used in the production of pharmaceutical, biotechnology, injectables, and food and beverage products.
- Any processes that require long-term exposure to heat or tension, detailed customization, or extreme hardness. Key attributes of platinum-cured silicone include high tear and tensile strength, very low shrinkage, fine detail reproduction, and an extensive range of hardnesses.
Other industries in which platinum-cured silicone molds and tubing are used include manufacturing of automotive products, electronics, clothing and footwear, food storage products, and more. For detailed information about potential applications, contact SIMTEC to speak directly with one of our engineers.