Saltar al contenido
PTI LATAMExplorar Portal
🇲🇽 Español🇺🇸 English🇧🇷 Português
Hules

Silicone Rubber (VMQ)

An inorganic elastomer based on a silicon-oxygen polymer backbone (polysiloxane) that provides the widest useful temperature range of any commercial rubber: -60 to +230°C continuous (special grades to -100°C and +300°C). The Si-O bond is inherently more stable than the C-C bonds of organic rubbers, giving silicone exceptional thermal, oxidative, and UV resistance. Key properties: FDA and USP Class VI biocompatibility (non-toxic, odorless, tasteless), excellent ozone and weathering resistance (essentially permanent outdoor exposure), outstanding electrical insulation (dielectric strength 15-25 kV/mm), and low compression set at extreme temperatures. Limitations: lowest tensile strength among common elastomers (5-10 MPa), poorest abrasion resistance, attacked by steam and some hydrocarbon solvents, relatively high cost ($8-25/kg). ASTM D2000: FC/FE/GE. Applications: food-grade seals and gaskets, medical devices and implants, oven door gaskets, automotive spark plug boots, LED encapsulation, baby care products, and high-voltage insulators. Types: solid HCR (high consistency, compression/extrusion molded) and liquid LSR (two-component, injection molded).

What you need to know

  • An inorganic elastomer based on a silicon-oxygen polymer backbone (polysiloxane) that provides the widest useful temperature range of any commercial rubber: -60 to +230°C continuous (special grades to -100°C and +300°C).
  • The Si-O bond is inherently more stable than the C-C bonds of organic rubbers, giving silicone exceptional thermal, oxidative, and UV resistance.
  • Key properties: FDA and USP Class VI biocompatibility (non-toxic, odorless, tasteless), excellent ozone and weathering resistance (essentially permanent outdoor exposure), outstanding electrical insulation (dielectric strength 15-25 kV/mm), and low compression set at extreme temperatures.
  • Limitations: lowest tensile strength among common elastomers (5-10 MPa), poorest abrasion resistance, attacked by steam and some hydrocarbon solvents, relatively high cost ($8-25/kg).
  • ASTM D2000: FC/FE/GE.

Full definition

Silicone rubber, known chemically as VMQ (Vinyl Methyl Silicone), is a versatile inorganic elastomer characterized by its silicon-oxygen polymer backbone (polysiloxane). This unique structure allows silicone rubber to maintain its elasticity and mechanical properties over an exceptionally wide temperature range, from -60°C to +230°C under continuous use, with certain special grades extending this range from -100°C to +300°C. The stability of the Si-O bond, which is more resilient than the C-C bonds found in organic rubbers, contributes to silicone's resistance to thermal degradation, oxidative damage, and UV exposure, making it an ideal choice for applications requiring prolonged outdoor exposure and extreme temperature performance.

The properties of silicone rubber extend beyond temperature tolerance. It is biocompatible, classified under FDA and USP Class VI, meaning it is non-toxic, odorless, and tasteless, which is crucial for applications in the food and medical sectors. Its excellent ozone and weathering resistance ensure durability even in harsh environmental conditions. Furthermore, silicone exhibits outstanding electrical insulation properties, boasting a dielectric strength ranging between 15-25 kV/mm, making it suitable for high-voltage applications. One notable advantage is its low compression set at extreme temperatures, which allows it to maintain its shape and sealing effectiveness over time.

However, silicone rubber does have limitations. It has the lowest tensile strength among common elastomers, typically ranging from 5-10 MPa, and possesses poor abrasion resistance. Additionally, it can be vulnerable to steam and certain hydrocarbon solvents, which may limit its applications in some environments. The cost of silicone rubber is also relatively higher, ranging from $8 to $25 per kilogram, which can influence its selection for various projects. Silicone rubber is available in different forms, primarily solid HCR (high consistency rubber) which is compression or extrusion molded, and liquid LSR (liquid silicone rubber) that is typically used in two-component injection molding processes.

What you need to know

  • What you need to know: Silicone rubber (VMQ) operates effectively in a temperature range of -60°C to +230°C continuously.
  • It demonstrates exceptional thermal, oxidative, and UV resistance due to its stable Si-O bonds.
  • Silicone rubber is biocompatible, making it suitable for FDA and USP Class VI applications such as food and medical devices.
  • It has a dielectric strength of 15-25 kV/mm, ensuring excellent electrical insulation.
  • Common limitations include low tensile strength (5-10 MPa) and vulnerability to certain solvents.
  • Silicone rubber typically costs between $8 and $25 per kilogram.

Industrial applications

  • 1Food-grade seals and gaskets for food processing equipment to ensure safety and hygiene.
  • 2Medical devices and implants requiring biocompatibility and stability in various conditions.
  • 3Oven door gaskets that withstand high temperatures while maintaining sealing integrity.
  • 4Automotive spark plug boots that require electrical insulation and heat resistance.
  • 5LED encapsulation materials to protect sensitive components from moisture and environmental exposure.

Common mistakes

  • ✕Using silicone rubber in applications that involve prolonged contact with steam or certain hydrocarbon solvents, leading to degradation.
  • ✕Overlooking the relatively low tensile strength of silicone rubber, which can result in premature failure in high-stress applications.
  • ✕Neglecting to consider the cost implications of silicone rubber, especially in large-scale applications where alternatives may be more cost-effective.
  • ✕Ignoring the specific formulation (HCR vs. LSR) needed for the intended manufacturing process, which can impact production efficiency.
💡

Pro tip

When selecting silicone rubber for a specific application, consider the environmental conditions and stress factors to ensure optimal performance.

Technical standards

  • ASTM D2000 - Standard Classification System for Rubber Products in Automotive Applications
  • FDA - Food and Drug Administration guidelines for biocompatibility
  • USP Class VI - United States Pharmacopeia standards for materials used in medical devices

Suppliers of industrial rubber in Mexico

AguascalientesVer Hule Industrial
Ciudad JuárezVer Hule Industrial
Ciudad de MéxicoVer Hule Industrial
GuadalajaraVer Hule Industrial
Cotiza en tu ciudad

Applicable standards

ASTM D2000
Back to glossary