Silicone (Silicone Rubber) Material Guide

Overview

Silicone Rubber is a high-performance elastomer known for its exceptional temperature resistance, flexibility, biocompatibility, weather resistance, electrical insulation, and chemical stability.

Unlike conventional organic rubbers, silicone is based on a silicon-oxygen molecular backbone, enabling superior performance across extreme temperatures and harsh environmental conditions. Silicone remains flexible at low temperatures while maintaining stability at elevated temperatures, making it one of the most versatile elastomer materials available.

Silicone is widely used in:

  • Medical Devices
  • Food Processing Equipment
  • Automotive Components
  • Electronics & Electrical Systems
  • Aerospace Applications
  • Consumer Products
  • Industrial Sealing Systems
  • Wearable Devices

Due to its excellent durability, safety, and environmental resistance, silicone is one of the most commonly specified elastomers for demanding engineering applications.


Material Specification

PropertyValue
Material DesignationSilicone
Full NameSilicone Rubber
Material FamilyElastomer
Density1.10–1.50 g/cm³
AppearanceTransparent, White, Black, Colored
Hardness RangeShore A 10–90
Typical Manufacturing MethodsCompression Molding, Injection Molding, Extrusion, LSR Molding
Standard FormsSheets, Rolls, Tubes, Profiles, Molded Parts

Chemical Composition

Silicone consists primarily of polysiloxane polymers.

ComponentFunction
Polysiloxane PolymerElastic Matrix
Silica FillersStrength Enhancement
Crosslinking AgentsCuring System
PigmentsColor Control
AdditivesPerformance Enhancement

The silicon-oxygen backbone provides outstanding thermal and environmental stability.


Common Silicone Grades

GradeCharacteristics
General Purpose SiliconeStandard Industrial Applications
Medical Grade SiliconeBiocompatible
Food Grade SiliconeFDA & LFGB Compliant
High-Temperature SiliconeExtreme Heat Resistance
Conductive SiliconeEMI Shielding Applications
Liquid Silicone Rubber (LSR)Precision Molding

Mechanical Properties

Typical Values

PropertyValue
Tensile Strength5–12 MPa
Elongation at Break150–700%
Tear Strength15–50 kN/m
Compression SetLow
HardnessShore A 10–90
ResilienceExcellent

Typical Mechanical Performance

PropertyPerformance
FlexibilityOutstanding
Elastic RecoveryOutstanding
Tear ResistanceGood
Fatigue ResistanceExcellent

Silicone maintains elasticity over long service periods.


Physical Properties

PropertyValue
Density1.10–1.50 g/cm³
Water AbsorptionVery Low
Thermal Conductivity0.15–0.30 W/m·K
Gas PermeabilityHigh
UV ResistanceOutstanding

Silicone performs exceptionally well in outdoor environments.


Thermal Properties

PropertyValue
Continuous Service Temperature-60°C to 200°C
High-Temperature GradeUp to 250°C
Short-Term Temperature ResistanceUp to 300°C
Brittleness TemperatureBelow -70°C

Silicone offers one of the widest operating temperature ranges among elastomers.


Strength-to-Weight Ratio

MaterialDensity (g/cm³)Tensile Strength
Silicone1.208 MPa
EPDM1.1510 MPa
NBR1.2015 MPa
Natural Rubber0.9320 MPa

While not the strongest elastomer, silicone excels in thermal and environmental durability.


Chemical Resistance

Chemical EnvironmentPerformance
WaterOutstanding
OzoneOutstanding
UV ExposureOutstanding
WeatheringOutstanding
AlcoholsGood
Dilute AcidsGood
Dilute AlkalisGood
Petroleum OilsModerate
FuelsPoor

Silicone is ideal for outdoor and environmental exposure applications.


Weather & UV Resistance

PropertyPerformance
UV ResistanceOutstanding
Ozone ResistanceOutstanding
Outdoor DurabilityOutstanding
Aging ResistanceOutstanding

Silicone can maintain performance outdoors for decades.


Electrical Properties

PropertyValue
Volume Resistivity>10¹⁴ Ω·cm
Dielectric Strength18–25 kV/mm
Dielectric Constant2.8–3.3
Arc ResistanceExcellent

Silicone is widely used as an electrical insulation material.


Biocompatibility

PropertyPerformance
Skin Contact SafetyExcellent
Medical CompatibilityExcellent
Food Contact ComplianceAvailable
Hypoallergenic PerformanceExcellent

Medical-grade silicone is extensively used in healthcare and wearable products.


Compression Set Resistance

PropertyPerformance
Compression RecoveryExcellent
Seal RetentionExcellent
Long-Term ElasticityExcellent
Gasket PerformanceOutstanding

Silicone is widely used for seals and gaskets due to its low compression set.


Manufacturing Characteristics

Manufacturing ProcessRating
Compression MoldingOutstanding
Injection MoldingOutstanding
ExtrusionOutstanding
Liquid Silicone Molding (LSR)Outstanding
OvermoldingExcellent

Silicone is highly versatile for both low-volume and high-volume manufacturing.


International Equivalent Grades

StandardEquivalent Grade
ASTM D2000Silicone Rubber
ISOVMQ
DINSilikon-Kautschuk
JISSilicone Rubber
GB/T (China)硅橡胶
FDAFood Grade Available
USP Class VIMedical Grade Available

Available Forms

Product TypeAvailability
SheetsYes
RollsYes
TubesYes
Extruded ProfilesYes
Molded PartsYes
Liquid Silicone RubberYes

Typical Applications

Medical Industry

  • Catheters
  • Respiratory Components
  • Prosthetic Components
  • Medical Seals

Food Processing Industry

  • Food Contact Gaskets
  • Baking Molds
  • Beverage Equipment Seals
  • Food Transfer Tubing

Automotive Industry

  • Engine Gaskets
  • Ignition Components
  • Weather Seals
  • Sensor Covers

Electronics Industry

  • Keypads
  • Insulators
  • Cable Protection
  • Thermal Interface Components

Aerospace Industry

  • Environmental Seals
  • Cabin Components
  • High-Temperature Gaskets

Consumer Products

  • Wearables
  • Kitchen Products
  • Baby Products
  • Personal Care Devices

Advantages

Exceptional Temperature Resistance

Operates reliably from -60°C to 200°C and beyond.

Outstanding UV & Weather Resistance

Ideal for long-term outdoor applications.

Excellent Flexibility

Maintains elasticity in extreme temperatures.

Biocompatibility

Suitable for medical and food-contact applications.

Superior Electrical Insulation

Excellent dielectric performance.

Long Service Life

Resists aging, ozone, and environmental degradation.


Limitations

Lower Tensile Strength

Weaker than many conventional elastomers.

Poor Fuel Resistance

Not recommended for gasoline exposure.

Higher Material Cost

More expensive than EPDM and NBR.

Higher Gas Permeability

Not ideal for high-pressure gas sealing applications.


Comparison with Common Elastomers

PropertySiliconeEPDMNBRFKM (Viton)
Temperature ResistanceOutstandingExcellentModerateOutstanding
UV ResistanceOutstandingExcellentPoorGood
Oil ResistanceModeratePoorExcellentOutstanding
Flexibility at Low TemperatureOutstandingGoodModerateGood
CostHighLowLowVery High

Comparison with EPDM

PropertySiliconeEPDM
High Temperature ResistanceBetter
Low Temperature FlexibilityBetter
Food Contact CompatibilityBetter
Fuel ResistanceSimilar
CostHigher

Silicone is often selected when temperature resistance and biocompatibility are critical.


Available Surface Finishes

Standard Finishes

  • Matte Finish
  • Smooth Molded Finish
  • Textured Finish

Functional Finishes

  • Medical Grade Surface
  • Food Grade Finish
  • Anti-Microbial Surface

Specialty Grades

  • Medical Grade Silicone
  • Food Grade Silicone
  • High Temperature Silicone
  • Conductive Silicone
  • Liquid Silicone Rubber (LSR)

Frequently Asked Questions (FAQ)

What is Silicone?

Silicone is a synthetic elastomer based on a silicon-oxygen backbone, known for exceptional temperature resistance, flexibility, and environmental durability.

What is Silicone used for?

Typical applications include:

  • Medical Devices
  • Food Processing Equipment
  • Automotive Seals
  • Electrical Insulators
  • Consumer Products

Is Silicone food safe?

Yes. Food-grade silicone complies with FDA and LFGB regulations.

Is Silicone biocompatible?

Medical-grade silicone is highly biocompatible and widely used in healthcare applications.

Is Silicone resistant to UV and weather?

Yes. Silicone provides some of the best UV and weather resistance among elastomers.

Why choose Silicone?

Because it combines:

  • Extreme Temperature Resistance
  • Outstanding UV Resistance
  • Excellent Flexibility
  • Biocompatibility
  • Long Service Life

What is the difference between Silicone and EPDM?

Silicone offers superior temperature resistance and biocompatibility, while EPDM typically provides lower cost and slightly better mechanical strength.

Does GCNOV provide Silicone manufacturing services?

Yes. GCNOV provides:

  • Silicone Compression Molding
  • Liquid Silicone Rubber (LSR) Injection Molding
  • Extrusion Services
  • Medical Silicone Components
  • Food Grade Silicone Products
  • Prototype Development
  • Low-Volume Production
  • Mass Production