Material Safety Data Sheet for Silicone Rubber

Identification

Product Name: Silicone Rubber
Synonyms: Methylvinyl Silicone, Polydimethylsiloxane elastomer
Recommended Use: Sealing, molding, coating, electrical insulation
Supplier: Common global manufacturers include Dow, Wacker, Shin-Etsu, Momentive
Contact Information: Factory address and emergency contact phone listed on product barrel or datasheet
Emergency Phone Number: Prompt 24-hour service line provided on packaging
Chemical Family: Organosilicone Compound
Chemical Formula: (C2H6OSi)n
UN Number: Not classified as hazardous for transport

Hazard Identification

GHS Classification: Not classified as hazardous under GHS
Signal Word: None
Hazard Statements: Slippery when spilled; residue can increase fall risk; may emit formaldehyde vapors at high temperature
Precautionary Statements: Wash hands after handling; avoid direct inhalation of heated fumes; ensure ventilation when cutting or ablating
Potential Health Effects: Direct contact rarely irritates skin or eyes; uncured material may cause mild irritation
Routes of Exposure: Eyes, skin, inhalation (if heated above 180°C), ingestion accidental but rare
Environment Hazards: Not expected to be harmful, but persistent

Composition / Information on Ingredients

Main Ingredient: Polydimethylsiloxane (CAS No. 63148-62-9, over 60%)
Crosslinker: Methylhydrogen siloxane, traces less than 2%
Filler: Fumed silica (CAS No. 112945-52-5, 15-40%)
Colorants and Additives: Vary by product, iron oxides for color, platinum or peroxide catalyst less than 1% in platinum-cured or peroxide-cured rubbers
Impurities: None present above relevant reporting levels

First Aid Measures

Eye Contact: Gently flush eyes with water for at least 15 minutes; remove contact lenses; seek medical help if irritation continues
Skin Contact: Clean skin with soap and water; take off contaminated clothing; long-term skin exposure unlikely to cause injury
Inhalation: Move to fresh air; exposed to fumes or smoke, seek medical advice; high-heat decomposition may release formaldehyde
Ingestion: Rinse mouth with water; small amounts unlikely to cause harm; get medical advice for large amounts
Advice for Doctor: Treat symptoms; no specific antidote

Fire-Fighting Measures

Suitable Extinguishing Media: Water spray, foam, dry chemical, or carbon dioxide
Unsuitable Extinguishing Media: High-pressure water jet can spread molten material
Specific Hazards: At high temperature, releases formaldehyde, carbon oxides, silicon oxides; thick smoke possible; decomposition starts above 220°C
Protective Equipment: Self-contained breathing apparatus and protective clothing
Special Precautions: Do not enter confined space without full protective gear; cool containers with water; avoid runoff into sewers

Accidental Release Measures

Personal Precautions: Avoid walking on spilled silicone rubber; falls possible; use proper safety shoes
Protective Equipment: Gloves for large or uncured spills; goggles if splashing possible
Environmental Precautions: Prevent product from flowing into drains; avoid water contamination
Clean-Up Methods: Collect bulk material with shovel or scraper; use absorbent for residues; dispose of as solid industrial waste in sealed container

Handling and Storage

Safe Handling: Handle with clean, dry gloves in ventilated areas; avoid contamination with acids or strong bases; do not eat or drink in work area
Storage Conditions: Store in original, sealed packaging below 30°C; avoid freezing or direct sunlight; keep away from strong oxidants
Incompatible Materials: Strong acids, bases, peroxides; avoid storing with food or animal feed
Advice on General Occupational Hygiene: Wash hands after use; keep work areas tidy; label open containers clearly

Exposure Controls and Personal Protection

Occupational Exposure Limits: No established limits for main polymer; silica dust limit applies if airborne dust is generated during processing
Engineering Controls: General room ventilation; local exhaust for melting, mixing, or sawing operations
Respiratory Protection: Not required for routine handling; mask if dust or fumes generated
Hand Protection: Protective gloves encouraged for prolonged use
Eye/Face Protection: Safety glasses when mixing or pouring
Skin Protection: Long sleeves optional, more important for uncured rubbers
Hygiene Measures: Wash up before breaks and after work

Physical and Chemical Properties

Form: Elastic solid or viscous liquid before curing
Color: Typically translucent, white, or colored as specified by supplier
Odor: Mild, none for cured, may have acetic or vinegar odor during curing
pH: Not applicable
Melting Point: Not specified, softens between 100°C and 200°C
Boiling Point: Not applicable; decomposes
Flash Point: Above 300°C (closed cup)
Flammability: Not classified as flammable, will burn at high temperature
Explosive Limits: Not applicable
Vapor Pressure: Low (nearly zero at room temperature)
Solubility: Insoluble in water
Density: 1.1–1.4 g/cm³ for most grades
Partition Coefficient: Not applicable
Auto-ignition Temperature: Over 450°C
Decomposition Temperature: Above 280°C
Viscosity: Depends on pre-cure formulation, generally high for pastes/putty types

Stability and Reactivity

Chemical Stability: Stable under normal temperatures and conditions
Reactivity: Does not react in normal environment; reacts slowly with strong oxidizers
Conditions to Avoid: Extended exposure to strong acids, bases, high heat
Hazardous Decomposition: Burning releases carbon oxides, silicon oxides, formaldehyde in trace amounts
Hazardous Polymerization: Will not occur under correct usage

Toxicological Information

Likely Exposure Routes: Skin, eyes, inhalation of fumes or dust
Acute Toxicity: Not acutely toxic by dermal or oral exposure
Chronic Effects: Continuous skin exposure does not lead to sensitization in most users; rare allergic contact possible with uncured catalysts
Medical Conditions Aggravated by Exposure: Existing chronic respiratory or skin conditions, only if exposure prolonged or improper use
Aspiration Hazard: Unlikely, product is not a liquid
Sensitization: Unlikely, but limited cases noted with uncured products

Ecological Information

Persistence and Degradability: Not biodegradable; slowly breaks down to silica, water, and CO2 over decades
Bioaccumulation: Does not accumulate in food chain
Mobility in Soil: Low; sticks to soil and sediment
Aquatic Toxicity: Not toxic to fish and aquatic organisms; insoluble, does not dissolve or spread
Other Hazards: Large spills can choke water flow or impact small wildlife physically

Disposal Considerations

Product Disposal: Landfill or incinerate as industrial waste; follow local regulations
Container Disposal: Empty packaging can be landfilled or recycled after cleaning
Special Precautions: Do not pour into sewers, lakes, or rivers
Waste Code: Non-hazardous, but check local rules
Recommended Practices: Use up remaining material; seal in sturdy waste bags for contractor pickup

Transport Information

UN Number: Not regulated as hazardous
Proper Shipping Name: Silicone Rubber Compound
Transport Hazard Class: Non-hazardous
Packing Group: Not assigned
Environmental Hazards: No labeling required
Special Transport Precautions: Protect from direct sunlight and freezing; avoid container damage during transit

Regulatory Information

OSHA Status: Not classified as hazardous under US OSHA Hazard Communication Standard
TSCA Inventory: All components listed
REACH Registration: Registered as polymer in EU REACH
Hazard Pictograms: None required
Labeling Requirements: Name and contact information of manufacturer
Chemical Safety Assessment: Regular corporate assessment required for large-scale users
Other Regulations: Follow country-specific rules for workplace exposure and waste disposal; silicone rubbers used in medical or food applications require certification according to end use