Introduction
Silicone is considered a very versatile material and has become an essential component in various sectors such as automotive, construction, electronics, healthcare and consumer goods. It possesses unique properties like heat resistance, chemical stability and flexibility which makes it a preferred material for a wide range of applications. However, every type of silicone has different grades, characteristics, performance and regulatory requirements. It is important to choose the correct type of silicone for one’s application. Choosing the correct silicone can be critical and can directly impact the performance and longevity of the products.
Factors to Be Considered While Choosing the Right Silicone
Below stated are the 6 main factors to keep in mind while choosing the correct silicone for one’s applications:
- Temperature Exposure: One should always know at what temperature will the material operate and what is the minimum and maximum ranges of the temperatures. Temperature exposure of silicone is considered a pivotal consideration as it directly impacts performance of the application. One should always choose the silicone that aligns the temperature resistance rating of the applications to make the material performance more optimal and durable. One should also consider different temperature parameters such as the maximum and minimum ranges. It is advisable to refer to the technical data sheet of the applications to find their respective temperature parameters.
- U/V Ozone and Radiation Resistance: It is important to check whether the materials will be processed outdoors and be exposed to UV, ozone or radiations. Silicone is resistant to radiation, oxygen, ozone and U/V lights. The silicone-oxygen bonds of silicone’s inorganic compounds are more stable as compared to carbon atoms in organic polymer chains. Also, the energy provided by U/V rays can break the carbon-carbon bonds but cannot damage the silicone’s Si-O bonds easily. Silicone’s resistance to radiation, oxygen, ozone and U/V lights makes it suitable for outdoor applications and harsh environments. This resistance capacity is also a reason why silicone can be sterilized for many medical and life science applications. It can be easily sterilized using gamma rays, electron beam radiation, Ethylene Oxide Sterilization and traditional Autoclave Steam Sterilization.
- Flame Resistance: Another important aspect to consider is the involvement of flame, correct flame ratings and fire safety of the application. In the cases where fire safety is a concern, one should consider a silicone material that meets at least one of the industry-recognized flame ratings. These are UL94 V0/HBF/HB for the industrial sector, FMVSS-302 for automotive, FAR 25.853 and FAR 25.856 for aircraft, NFPA 130 and EN45545 requirements for railway.
- Chemical and Fluid Resistance: It is important to determine whether the material will be exposed to any chemicals or fluids. Usually, silicone is also resistant to chemicals, fuel and oil at temperatures that might eliminate other elastomers. However, it is advisable to use fluorosilicone if the material requires high chemical resistance. There is a possibility that materials may show some swelling if the silicone encounters chemicals or fluids. Once the material is removed from the fluid, it returns to its original shape. However, it might show little loss of its properties.
- Outgassing: It is important to determine whether the application is sensitive to contamination. It is always a concern that what could possibly outgas from the material. Thus, silicone cellular foams are formulated and post cured to reduce the available outgassing components. This makes them ideal for electronics since there are very low level of contaminants that can interfere in the applications.
- Budget: The most important factor is one’s budget for the application. One should determine if a high-quality material can help in preventing failure and injury. As silicones are more expensive than other elastomers, it is advisable to evaluate the market risk and reward. It is important to ask questions like can one risk a failure in the field of expensive warranty claims, can one risk a preventable injury due to the device and can one risk their reputation in the market. All these factors should be considered before choosing the correct silicone.
Importance of Grade Selection While Choosing the Silicone
The selection of correct silicone grade is far more than just a technicality. It directly influences the overall performance, longevity and safety of the products. Choosing the wrong grade can result into failure in meeting performance standards, compliance issues and may arise safety hazards. For example, if industrial-grade silicone is used for medicinal implants, it could pose a risk due to its lower purity and biocompatibility. It can also lead to certain adverse effects on the body. On the other hand, if a higher-grade silicone is chosen for non-critical applications, it could result in to wastage of resources. It can also increase the production cost significantly without providing any value in the process. Thus, it is advisable to understand the factors that can affect silicone grade selection. This ensures the best balance of quality, performance and cost-effectiveness. It is important to note that higher grade does not mean better, it means fit-to-purpose.
Some key types of silicone grades are industrial grade, food grade, medical grade, flame retardant grade, high strength grade and speciality grade.
Take Away
This is the brief explanation about silicone, factors to be considered while choosing it, importance of different silicone grades and its types. We hope this information will be effective for you. Please let us know through your valuable feedback and the suggestion in the drop box.