Both silicone and natural rubber are elastomers. The two are polymeric materials that display viscoelastic behavior (commonly known as elasticity).
We can differentiate silicone vs. rubber through the atomic structure. Moreover, silicone has more special features compared to natural rubber.
Based on these, let’s now look at the main difference between silicone vs. rubber.
Rubber is a strong elastic polymeric material made from the latex of rubber trees or synthetically in a lab. The chemical name of rubber is polyisoprene.
On other hand, silicone is a synthetic material that constitutes any inert, artificial compound comprising of replicating units of siloxane. The chemical name of silicone is polysiloxane.
1. Backbone Structure
Most types of rubber have a backbone containing carbon-carbon bonds.
However, the backbone structure of silicone includes an alternating oxygen atoms and silicon atoms sequence. Often, you will have the two atoms bonded with hydrogen and/or carbon.
2. Operating Temperature
Both silicone and rubber can function at very low temperatures, as low as -50 degrees Celsius. Nevertheless, you can use silicone material at much higher temperatures compared to rubber.
Natural rubber begins to disintegrate at 80 degrees Celsius and melts at 120 degrees Celsius. But, it is possible to formulate silicone to operate at temperatures as high as 230 degrees Celsius.
Silicone also has considerably greater flame resistance in comparison to rubber. Therefore, it is the better option for high temperature uses.
3. Resistance to Hydrocarbon Lubricants and Fuels
Neither natural rubber nor silicone have great resistance to hydrocarbon lubricants and fuels. Nonetheless, silicone displays a broader chemical resistance in comparison to rubber. This makes it a better option in chemical sealing applications.
However, your material selection for chemical application will depend on the specific chemicals you will expose the material to. You can use both materials in applications like tank lining and piping.
4. Tear and Tensile Strength
Rubber displays much higher abrasion resistance, tear strength, and tensile strength compared to silicone. This is the main reason it finds use in extreme wear applications like conveyor belts and tire treads.
5. Ultra-violet Light and Weathering Resistance
Silicone exhibits greater resistance to UV light and weathering. For this reason, you can use it in outdoor applications like window and door seals.
But, rubber weathers very fast and is not ideal for outdoor applications. Therefore, silicone is the perfect alternative for applications involving exposure to environmental elements.
The lifespan of silicone is about 4 times longer than that of rubber. Although its price is approximately double the price of natural rubber. Using silicone, therefore, might help you save on cost in the long-term.
7. Stabilizing Additives
You need special additives for stabilizing rubber. However, quality silicone production does not need addition of any stabilizing agent.
Silicone material commonly finds use in food processing and medical industries because of its unique features compared to rubber.
Its durability, high temperature and abrasion resistance makes it the better option in comparison to rubber.
A versatile more hygienic structure, less contamination, and long term cost savings all add to the benefits of using silicone.
As you can see, silicone is a perfect choice for more specialized applications than rubber. However, before choosing any of these materials, you should know their physical and chemical properties.
If you have any questions on silicon or rubber materials, contact us now.