Benefits of silicone
Silicone has great benefits and advantages over different materials such as rubber. Throughout this reading, we will find a summary where we can get an idea of what a silicone is like structurally, so that we can finally understand why we get such good benefits from it.
1. What is silicone?
Silicone is a polymer composed mainly of Silicon (Si). It is a combination of an inorganic skeleton of Silicon-Oxygen (Si-O) together with other organic functional groups on the side of the chains.
The starting material from which silicones are produced is silica (silicon dioxide), common in sandstone, beach sand or quartz. Silica is also widely used in glass production. It is the way in which it is obtained by polymerization that denotes the difference in properties between silicones and glass.
Frederick Kipping was the pioneer in the study of organic compounds containing carbon and silicon molecules and it was he who gave the name of silicon.
Silicone can take different physical forms, such as oils, gels, and solids. This is why it is a very versatile type of rubber, which can be used in many applications where wide working temperature ranges, stability, resistance, etc. are required.
2.1 Types of silicone rubber
- Silicone oils: used in cosmetics
- LSR ( Liquid silicone rubber ): normally used in injection molding.
- VMQ ( High consistency silicones): tubes for food and pharmaceutical use and medical applications.
- FVMQ (Fluorosilicone): better resistance to oils and hydrocarbons.
2.2 Silicone curing systems
With the exception of RTV or liquid silicones, silicone rubber is normally cured with peroxides by application of temperature, requiring subsequent post cure to remove any volatiles that may remain in the silicone.
Another cure system for silicones is done with Platinum, obtaining silicones that comply with FDA (Food and Drug Administration) and USP VI regulations, making them suitable for use in contact with food and pharmaceutical products.
- Chemical stability
- Stability against adverse weather conditions, humidity, ozone, UV light.
- Thermal resistance in a wide range of Tª (-55 ºC - 230 ºC).
- Resistance to oils through the incorporation of additives.
- Elasticity, malleability, and flexibility, as well as high tensile strength.
- Excellent electrical insulation properties.
- Anti-foam properties.
- Odorless and colorless.
- Inert material.
- FDA and USP Class VI compliant food grade silicones for food, medical and pharmaceutical use
- Microbial resistance
1. Stability and resistance
These are two qualities that go hand in hand in silicones. Due to their polymeric molecular structure and the arrangement of their Si-O bonds, silicones acquire properties that make them resistant to a wide range of temperatures: from -55 ºC (-67 ºF) to 300 ºC (572 ºF) depending on the formulation.
Also, its stability against the harmful effects of time, sunlight, humidity, ozone and various chemicals, makes it a very versatile type of rubber, which can be used in many applications.
Silicone is an odorless and colorless rubber. As mentioned above, the curing of silicones with Platinum allows them to be for food, medical, and pharmaceutical use. For optimum purity where 0 impurities are required, some application-specific silicones are processed in ISO 7 rooms, where the internal environment is constantly cleaned from external agents that may affect the silicone. In this way, they can comply with both FDA and USP Class VI regulations, offering high-quality products.
Silicone is one of the materials that offers greater resistance to ozone, oxygen... therefore, they do not need the addition of antioxidants or antiozonants to have greater durability and stability over time. With respect to working conditions, they are capable of withstanding high working pressures for long periods of time.
4. Flexibility and adaptability
If great flexibility is needed in a material, silicone is the best option to obtain the desired adaptability. Silicone resists large deformations and vibrations and is used with excellent results in engines, for example.
By adding additives to the silicone, the properties of the silicone can be modified, opening up a wide range of possibilities for specific applications. Examples of benefits obtained by the incorporation of additives can be, among others
5. Resistance to oils of a silicone.
The resistance to oils can be improved by the incorporation of additives.
6. Antimicrobial action.
Silicones already intrinsically have an antimicrobial function, but this property can also be improved by the addition of specific fillers to obtain silicones for medical use in which the increased antimicrobial action is very beneficial for the prevention of infections that could be transferred if another material were used.