Silicone Rubber Parts
Silicone rubber parts are found in a variety of applications. Typical designs include voltage line insulators, electrical connectors, medical devices, and rubber-to-metal bonded components.
Liquid injection molding (LIM) is the preferred manufacturing process for silicone rubber parts. This involves pumping the two-part liquid silicone and catalyst into a mold cavity where it is cured.
Flexibility
Silicone rubber parts have a lot of flexibility. Unlike plastics, which are stiff and unbending, silicone rubber is soft and bendy. It can also be formed into many different shapes and sizes.
Liquid silicone rubber (LSR) is a versatile material that can be molded into various items like voltage line insulators, automotive applications, cooking, baking and food storage products, apparel including undergarments and sportswear, electronics, home repair and hardware and Silicone Pet Supplies more. It can also be calendered into thick sheets of material to create custom fabricated products and parts.
Compression molding and injection molding are popular fabrication methods for silicone rubber parts. These processes force raw material into a mold cavity that is closed and kept heated until the material cures. Silicone rubber can be used in this process in either a solid or liquid state, and it is also able to be extruded into long lengths of cord or custom profiles for a wide range of uses.
Temperature Resistance
Unlike other types of rubber, silicone does not melt when exposed to high temperatures. This helps protect the integrity of parts in extreme environments, including those that must endure abrasion or exposure to UV rays.
This exceptional temperature resistance is thanks to the unique molecular structure of silicone rubber, which includes a siloxane chain and a variety of organic chemical groups. This allows fabricators to include different additives to achieve the performance they require for a given application.
Some examples of these additives are reinforcing fillers (pyrogenic silica), functional additives (graphene nanosheets), and lubricants. Many of these materials are also available in a platinum-catalyzed form, which offers higher cure rates and eliminates the need for peroxide bloom during the curing process.
The thermal stability of silicone rubber is also influenced by the type and quantity of its heat-resistant additives and by its preparation technology. For instance, adding GNPs to silicone rubber enhances its thermal stability and mechanical properties by preventing the molecular movement of the siloxane chains.
Low-Stress Relaxation
Silicone rubber is very resilient and has high elasticity, even after long periods of exposure to high temperatures. This quality makes it suitable for a wide variety of applications and environments.
It can also be color friendly and easily molded Silicone Pet Supplies Manufacturer into different shapes and sizes with several techniques. Some examples include compression molding, liquid silicone injection (LSR) molding and extrusion.
Compression molding is a labor intensive process in which silicone rubber is pre-catalyzed before it is mixed with pigment and formed to the final shape. It is then compressed between two plates and heated to vulcanize (cure) the material.
Heat-curable elastomers like silicone are made with an inorganic Si-O backbone and organic functional groups. These are crosslinked at elevated temperatures with peroxides or platinum catalysts to form a solid, elastomeric product with excellent weather resistance and flex fatigue life. It’s possible to add additives to improve performance for specific applications. For example, pyrogenic silica can be added to increase the tensile strength of the material and carbon black increases conductivity behavior.
Durability
Silicone rubber is a versatile material valued for its flexibility, biocompatibility and resistance to extreme temperatures, UV radiation and ozone. It is available in many forms, including liquids, gels, foams and solids, and can be molded to create seals, O-rings, bellows, diaphragms, and more. It can also be shaped through a mechanical process called calendering, in which it is run through pairs of heated, hard steel rollers, each adjusted for pressure to produce a predetermined thickness and surface texture.
Silicone is an ideal choice for a variety of medical applications, including silicone catheters and tubing; wire/fluid-path coextrusions; and implantable devices. It is also used in aerospace, electrical and construction applications, as it resists vibration and weathering, and can bond to metals. In addition, silicone offers better chemical resistance than natural rubber, but this is dependent on the specific chemicals it will come into contact with.
Chemical Resistance
Silicone rubbers are highly resistant to corrosion, temperature fluctuations and electrical currents making them ideal for a variety of industrial applications. They also resist extreme conditions, such as UV radiation and ozone.
The chemical resistance of silicones stems from their unique molecular structure. Silicones have an inorganic backbone and a number of organic groups, including methyl, phenyl and vinyl groups (referred to as MQ, PVMQ, or VMQ). They are able to stand up to a variety of chemicals without reacting.
Silicones are also very stable materials that retain their physical properties over time and remain operational under a wide range of temperatures, making them the perfect material for medical components and devices. For instance, silicone can withstand high temperatures during sterilization processes and is highly resistant to various acidic chemicals. The high tensile strength and elasticity of silicones also make them ideal for a variety of medical devices.
Customization
Silicone rubbers can be transformed through a series of manufacturing methods to achieve specific characteristics like hardness, elasticity, transparency and resistance to environmental or mechanical stresses. This versatility is attributed to their unique molecular structure which carries organic and inorganic groups.
Liquid silicone injection molding, also known as LIM or liquid silicone rubber molding, utilizes highly viscous two-part liquid silicone and a platinum catalyst to accelerate cure times beyond those achievable with high consistency rubber (HCR) injection molding. This closed-loop molding process ensures that uncured raw silicone is never in contact with workers.
Silicone rubber extrusion produces hoses, cords and complex profiles shaped with custom dimensions that can be joined together to create seals or gaskets. Manufacturers work to set industry tolerances when extruding or cutting silicone rubber profiles to ensure consistent and high quality end-products. In addition, silicone rubber can be pigmented or textured with various additives to achieve specific design goals or functionality like anti-stick coatings.