Understanding the differences between silicone and fluorosilicone

Iranpolymer/Baspar Silicone and fluorosilicone are synthetic elastomers that are used extensively across various industry sectors. Due to the unique properties of these materials, they are often the preferred compound for manufacturing sealing products in the aerospace, medical and food industries. Although these materials share some properties, they differ significantly in their chemical compositions and functional capabilities. Seals Direct explores the differences between silicone and fluorosilicone including their chemical composition, chemical resistance, typical applications and cost considerations.

Silicone consists of silicon, oxygen and typically carbon and hydrogen atoms. It is known for its flexibility, heat resistance and insulation properties, which make it a popular choice in many applications. Silicone is used in everyday kitchen products such as spatulas and baking moulds, in medical devices including tubing and implants, and in protective enclosures for electronics.

Fluorosilicone includes the same base structure as silicone but is modified by the addition of fluorine atoms. This modification gives the material enhanced chemical resistance while retaining the characteristics of standard silicone, such as temperature endurance and suitability in medical and food industries. The addition of fluorine atoms makes fluorosilicone particularly resistant to fuels, solvents and oils.

Chemical resistance

The chemical resistance of a material is an important factor in determining its suitability for specific environments, especially in industries where exposure to harsh substances is common. This is where the fundamental differences between silicone and fluorosilicone become most apparent.

Silicone, in its standard form, offers a moderate level of chemical resistance that is suitable for most everyday applications. It is resistant to water and a wide range of chemicals which allow its use in various consumer and industrial products. However, silicone has its limitations and is susceptible to swelling and degradation when exposed to oils, solvents and hydrocarbon fuels. These substances can compromise its structural integrity and functionality which may lead to a shortened lifespan and reduced effectiveness in some applications.

Fluorosilicone is formulated to withstand aggressive chemical environments which significantly expand its usability in more demanding situations. The addition of fluorine atoms enhances its chemical resistance, particularly against oils, fuels and solvents. This attribute is important in applications where the material must maintain its properties and integrity despite being in constant contact with corrosive substances.  Fluorosilicone’s superior resistance helps prevent the material from swelling, cracking or breaking down, thus ensuring long-term performance and reliability.

Applications

The versatility of silicone has resulted in its widespread use in both consumer goods and various industrial sectors. In the consumer market, silicone is a staple in the kitchen, found in items such as non-stick spatulas, flexible baking moulds and heat-resistant oven gloves. As Silicone does not react with foods and can withstand high cooking temperatures, these applications take advantage of the materials excellent thermal properties and food safety.

In the medical field, silicone’s biocompatibility makes it ideal for use in a variety of devices, including tubing, catheters and implants. Its flexibility and resistance to microbial growth ensure that it performs reliably in sensitive applications and contribute to patient safety and comfort. Additionally, the electronics industry relies on silicone for its insulation properties in wires, sealants and protective enclosures to help prevent electrical failures and enhance the durability of devices.

This compares to fluorosilicone which has a place for specialised applications that are largely driven by its enhanced chemical resistance. This makes this material indispensable in more technically demanding fields such as the automotive and aerospace industries where components will be exposed to harsh chemical environments. This includes fuel hoses, O-rings and gaskets where resistance to various chemicals ensures that the product can prevent leaks and create an effective seal. This is vital in applications where even minor failures can lead to significant operational disruptions and safety risks.

Cost considerations

The economic differences between silicone and fluorosilicone can significantly influence the decision-making processes in product development and manufacturing.

Silicone is generally more cost-effective than fluorosilicone. Its lower price point makes it an attractive option for a wide array of applications where extreme chemical resistance is not a essential factor. The affordability of silicone is due to several factors which include its widespread availability and the relative simplicity of its production process.

interplasinsights