Silicone Rubber
Silicone rubber combines excellent heat resistance (-60 °C to 230 °C), electrical insulation, and biocompatibility. Available in HTV, LSR, and RTV grades, it is used in medical devices, food contact applications, automotive seals, and electronics.
Key Properties at a Glance
| Service Temperature | -60 °C to 230 °C (standard); to 300 °C (phenyl) |
|---|---|
| Hardness Range | Shore A 10 – 80; Shore 00 5 – 50 (gel) |
| Tensile Strength | 5 – 12 MPa (HTV); 6 – 10 MPa (LSR) |
| Elongation at Break | 200 – 800% |
| Volume Resistivity | 10¹⁴ – 10¹⁶ Ω·cm |
| Cure Systems | Peroxide (HTV) / Platinum addition (LSR, RTV-2A) / Tin condensation (RTV-1, RTV-2C) |
| Certifications | FDA 21 CFR 177.2600 / USP Class VI / LFGB / RoHS / REACH |
Range shown is category-wide; refer to individual grade COA for precise specs.
Featured Grades
Shore 30A Silicone Rubber
Shore 30A silicone rubber is a soft, flexible grade for applications requiring low compression force, excellent conformability, and gentle contact surfaces such as medical tubing, baby products, and soft sealing.
Shore 50A Silicone Rubber
Shore 50A silicone rubber is the most commonly specified mid-hardness grade. It balances sealing performance, resilience, and dimensional stability, making it suitable for O-rings, keypads, automotive seals, and baking molds.
Shore 70A Silicone Rubber
Shore 70A silicone rubber is a firm, high-strength grade suited for structural sealing, high-pressure gaskets, cable jacketing, and applications requiring dimensional rigidity under load.
Products & Grades/ 8
HTV Silicone Rubber (Heat-Vulcanized)
HTV (High-Temperature Vulcanization) silicone rubber is a mill-mixed gum compound cured at 150–200 °C using peroxide or platinum catalysts. Supplied as slab or strip and processed by compression molding, extrusion, or calendering.
LSR Liquid Silicone Rubber
LSR (Liquid Silicone Rubber) is a two-part, platinum-catalyzed addition-cure system supplied as pumpable liquid. Processed by injection molding (LIM) at 150–200 °C with fast cycle times, ideal for complex high-volume medical and consumer parts.
RTV-1 Silicone (One-Component)
RTV-1 (Room Temperature Vulcanization, one-component) silicone cures by reacting with atmospheric moisture. Supplied ready-to-use in cartridges or tubes, it is the standard sealant for construction glazing, sanitary joints, and general-purpose bonding.
RTV-2 Silicone (Two-Component)
RTV-2 (Room Temperature Vulcanization, two-component) silicone is a liquid rubber system cured by mixing a base compound with a crosslinker or catalyst. Available in addition-cure (platinum) and condensation-cure systems for mold making, casting, potting, and industrial sealing.
Addition vs Condensation Silicone
Addition-cure (platinum) and condensation-cure (tin) silicones differ in mechanism, by-products, shrinkage, and application suitability. Choosing the correct cure chemistry is critical for mold-making, medical, and food-contact applications.
Transparent Silicone Rubber
Transparent silicone rubber achieves high light transmittance (≥90%) while maintaining all the thermal, chemical, and biocompatibility properties of standard silicone. Used in optical applications, visible tubing, and aesthetic consumer goods.
Translucent Silicone Rubber
Translucent silicone rubber allows diffused light transmission, providing a milky-white or frosted appearance. Preferred where some light diffusion is desirable and full optical clarity is not required, such as LED diffusers, sealing strips, and decorative parts.
Silicone Color Masterbatch
Silicone color masterbatches are pre-dispersed pigment concentrates designed for uniform color let-down into silicone rubber compounds. Available in food-grade, heat-stable, and UV-resistant variants.
By End-Use/ 10
Silicone Rubber for Medical Tubing
Platinum-cured silicone rubber is the material of choice for medical-grade tubing due to its biocompatibility, sterilization resistance, and chemical inertness. Used in peristaltic pumps, drainage systems, catheters, and IV fluid delivery.
Implant-Grade Silicone Rubber
Implant-grade silicone rubber meets the most stringent biocompatibility requirements for long-term contact with living tissue. It must pass USP Class VI biological tests and ISO 10993 evaluations and is used in cardiovascular implants, neurostimulator components, and reconstructive devices.
Silicone Rubber for Baby Nipples
Soft, transparent LSR grades are the industry standard for baby nipples and pacifiers, offering food-contact safety, repeated sterilization capability, and absence of BPA, phthalates, and latex allergens.
Silicone Rubber for Baking Molds
Food-grade silicone rubber (Shore 40A–60A) is the preferred material for flexible baking molds and kitchen utensils due to its non-stick properties, thermal stability up to 230 °C, and compliance with FDA 21 CFR and LFGB food-contact regulations.
Silicone Rubber for Automotive Seals
Silicone rubber (Shore 50A–70A) is widely used in automotive sealing systems for its resistance to engine heat, coolant fluids, and ozone. Applied in door seals, HVAC gaskets, valve cover gaskets, and oil seals.
Silicone Rubber for Spark Plug Boots
High-voltage silicone rubber compounds (Shore 60A–70A) are engineered for spark plug boots, combining dielectric strength, heat resistance up to 200 °C, and resistance to engine fluids in the ignition system.
Silicone Rubber for Cable Insulation
Silicone rubber cable compounds offer continuous service from −60 °C to +200 °C with superior electrical insulation, flame retardancy, and flexibility. Used in industrial, automotive, military, and medical cable applications.
Silicone Rubber for Keypads & Buttons
Conductive and non-conductive silicone rubber compounds are used to manufacture keypad membranes, push buttons, and tactile domes for consumer electronics, industrial control panels, and medical devices.
Silicone Rubber for Construction Sealants
One- and two-component RTV silicone sealants are the standard for high-movement construction joints, curtain wall glazing, and weatherproofing due to their UV stability, elasticity, and adhesion to glass, aluminum, and stone.
Silicone Rubber for Watch Bands
Silicone rubber watch bands (Shore 40A–60A) offer sweat resistance, skin compatibility, UV stability, and color fastness, making them the leading material for sports watches, smartwatches, and fashion accessories.
Certifications/ 4
FDA 21 CFR Silicone Rubber
FDA 21 CFR 177.2600 is the U.S. federal regulation governing rubber articles intended for repeated contact with food. Silicone rubber meeting this standard is verified by extraction tests in heptane, water, and acetic acid media.
USP Class VI Silicone Rubber
USP Class VI is a biological test classification under the U.S. Pharmacopeia for plastics and elastomers used in pharmaceutical and medical applications. It requires passing systemic injection, intracutaneous, and implantation tests in animal models.
RoHS & REACH Compliant Silicone
RoHS (Restriction of Hazardous Substances) and REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) are EU directives regulating restricted substances in electronics and chemical products. Silicone rubber intrinsically complies with most RoHS restricted substances.
LFGB Certified Silicone Rubber
LFGB (Lebensmittel- und Futtermittelgesetzbuch) is the German Food and Feed Code. §30 and §31 regulate food-contact materials including rubber and silicone, requiring migration testing and a sensory non-impairment test.
Comparisons/ 4
HTV vs LSR Silicone Rubber
HTV (mill-mixed solid) and LSR (pumpable liquid) silicone rubbers serve overlapping markets but differ in processing, part complexity, volume economics, and biocompatibility tier. This guide helps buyers choose the right form for their application.
Silicone vs EPDM Rubber
Silicone rubber and EPDM are both widely used in weatherstripping, automotive seals, and outdoor applications. Silicone offers superior temperature range and biocompatibility; EPDM offers lower cost and better resistance to steam and hot water.
Silicone vs Nitrile Rubber
Silicone and nitrile (NBR) rubber serve as alternatives in sealing applications. Nitrile offers excellent oil and fuel resistance at moderate temperatures; silicone excels at high and low temperatures and in food-contact or medical use.
LSR vs Solid Silicone
LSR (Liquid Silicone Rubber) and solid silicone (HTV/HCR) are two forms of the same base chemistry with very different processing methods and economic profiles. LSR suits high-volume precision parts; solid silicone suits extrusion and compression applications.
Guides/ 2
Silicone Rubber Buyer Guide
A practical guide for procurement engineers and sourcing managers covering how to specify silicone rubber, evaluate supplier claims, request certification documents, and avoid common sourcing mistakes.
Silicone Rubber Grade Selection Guide
A structured guide to selecting the correct silicone rubber grade by application type, hardness requirement, certification need, and processing method. Covers HTV, LSR, RTV-1, RTV-2, and specialty grades.
FAQs/ 1
Silicone Rubber Specification FAQ
Answers to the most common technical questions from buyers about silicone rubber specifications, certifications, processing, and supplier qualification.
Read full answer →