Its chemical composition is what gives silicone special status among extruded rubber materials.
While silicone extrusions can be used in minimally-demanding applications such as vending machines or food processing equipment, they are also used in medical technology contexts, often as components in peristaltic pumps, which are used to pump IV fluids through infusion devices. Silicone extrusions are ideal for this purpose because of their durability, chemical inertness and flexibility.
Silicone’s molecular structure, which is a combination of organic and inorganic components, is responsible for its chemical inertness. However, silicone’s range of chemical compatibility is not unlimited; it is primarily used in systems that pump water-based fluid in medical contexts. Outside of the context of the bio-tech industry, silicone’s properties make it attractive for several reasons; its composition makes it suitable for uses in the food services industry where extruded profiles are used in the packaging of food items as well as in beverage tubing applications.
All rubber extrusions are formed by the same process; raw materials or stock are passed through an extruder where they are heated, pressurized and forced through a die that is designed to mold the stock into a new shape. When the stock emerges from the die and cools, it hardens and is then considered to be extruded. Extruded rubber is used in a wide variety of industrial and consumer applications from sealant solutions to rubber bumpers. The method of processing silicone is similar to that of other rubbers, but its naturally-high heat resistance requires higher processing temperatures during the extrusion process.
Before being processed, silicone stock is made up of fine silica. Once extruded, it becomes translucent. The extruded silicone can then be used in this state, especially in applications where clear, flexible tubing is necessary. However, it can be colored easily for use in applications in which color coding or aesthetic considerations are necessary. Its naturally clear color gives it an advantage over other rubber products, which are often naturally dark in color or opaque. Its natural heat resistance also makes silicone an excellent electrical insulation and sleeving solution, and silicone extrusions are often used in high and low-temperature electrical insulation applications.