Material Safety Data Sheet: Chlorobutyl Rubber (CIIR)
1. Identification
Product Name: Chlorobutyl Rubber
Synonyms: CIIR, Chlorinated Isobutylene–Isoprene Rubber
Chemical Class: Synthetic Elastomer
Supplier: Major chemical manufacturing companies (name and address required for each MSDS compilation)
Emergency Contact Number: Company’s designated emergency numbers
Product Use: Tire inner liners, pharmaceutical closures, protective clothing
CAS Number: 68441-53-2
2. Hazard Identification
GHS Classification: Not classified as hazardous under normal conditions
Hazard Statements: Not expected to cause serious health effects; product dust may cause slight respiratory irritation.
Label Elements: No pictograms, signal words optional per local requirements
Precautionary Statements: Avoid excessive dust formation, use in well-ventilated areas, minimize contact with eyes and skin.
Other Hazards: Possible static electricity accumulation; molten rubber may cause thermal burns.
3. Composition / Information on Ingredients
Chemical Name: Chlorobutyl Rubber
Chemical Formula: Copolymer of isobutylene, isoprene, and chlorinating agent
Major Constituents: Isobutylene (97-98%), Isoprene (1-3%), Chlorine (1-2%)
Additives: Trace processing aids or antioxidants
Impurities: Minor residues from polymerization; no known highly hazardous impurities.
4. First Aid Measures
Inhalation: Move to fresh air, seek medical attention if coughing or irritation continues.
Skin Contact: Wash with mild soap and water; remove contaminated clothing.
Eye Contact: Flush with copious clean water for at least fifteen minutes; seek medical examination if continued irritation.
Ingestion: Rinse mouth; seek medical care for large ingestions or if discomfort persists.
Note for Physician: Treat symptomatically; burns from molten rubber require standard wound care.
5. Fire-Fighting Measures
Suitable Extinguishing Media: Water spray, dry chemical, foam, carbon dioxide.
Unsuitable Media: High-velocity water jets.
Specific Hazards: Combustion will release toxic smoke including carbon monoxide, carbon dioxide, hydrogen chloride, hydrocarbons.
Firefighter Protection: Wear self-contained breathing apparatus and full protective equipment.
Additional Advice: Cool containers exposed to heat with water spray; avoid runoff entering sewers.
6. Accidental Release Measures
Personal Precautions: Use appropriate personal protective equipment, ventilate area.
Environmental Precautions: Prevent material from entering drains or watercourses.
Cleanup Methods: Collect using non-sparking tools; sweep or vacuum spilled material; place in suitable containers for recycling or disposal.
Reporting Requirements: Report significant spills to regulatory authorities as required.
7. Handling and Storage
Handling: Use adequate mechanical ventilation; ground handling equipment to prevent static accumulation.
Avoid: Sources of ignition, contact with strong oxidizers.
Storage Conditions: Store at cool, dry, well-ventilated locations away from heat sources or sunlight.
Storage Compatibility: Keep away from strong acids, alkalis, oxidizing agents.
Packaging Materials: Store in original, tightly closed containers.
8. Exposure Controls and Personal Protection
Exposure Limits: No specific occupational exposure limits established.
Engineering Controls: Use local exhaust ventilation when processing or handling powders.
Personal Protection: Safety glasses with side shields, gloves resistant to physical or thermal hazard, long sleeves; in case of high dust or molten rubber exposure, use respirators and face shields.
Hygiene Measures: Wash hands after handling, remove contaminated clothing before meals or breaks.
9. Physical and Chemical Properties
Appearance: Off-white to light beige solid, typically in bales or slabs
Odor: Faint; characteristic of rubber
Odor Threshold: Not available
pH: Not applicable
Melting Point: 25-30°C (softens, does not have sharp melting point)
Boiling Point: Not applicable (decomposes before boiling)
Flash Point: >240°C
Evaporation Rate: Not available
Flammability: Not readily combustible
Vapor Pressure: Negligible at ambient temperatures
Vapor Density: Not applicable
Relative Density: 0.92 – 0.94
Solubility: Insoluble in water, soluble in aromatic hydrocarbons
Partition Coefficient (n-octanol/water): Not established
Decomposition Temperature: >300°C
Viscosity: Not applicable
Other Physical Data: Slight tackiness; may form fine powder during mechanical processing
10. Stability and Reactivity
Stability: Stable under normal conditions of storage and use.
Hazardous Reactions: No dangerous polymerization expected under recommended conditions.
Conditions to Avoid: Excessive heat, open flame, ignition sources.
Incompatible Materials: Strong acids, strong oxidizing agents.
Hazardous Decomposition Products: Fumes containing carbon monoxide, hydrogen chloride, carbon dioxide, hydrocarbons under combustion or pyrolysis.
11. Toxicological Information
Acute Toxicity: Low toxicity; ingestion and skin contact not expected to cause harm under normal conditions.
Inhalation: Mild irritation possible with dust; chronic effects not reported.
Skin Contact: No significant irritation in standard exposures; molten rubber may cause burns.
Eye Contact: May cause irritation; does not cause permanent injury.
Chronic Effects: No data indicates carcinogenicity, mutagenicity, reproductive toxicity; established tests show low toxicity.
Sensitization: Unlikely; rare cases of skin sensitization possible.
Other Data: No cumulative systemic effects from workplace exposure reported.
12. Ecological Information
Ecotoxicity: Not acutely toxic to aquatic or terrestrial organisms.
Persistence and Degradability: Will degrade slowly; not readily biodegradable.
Bioaccumulation: Potential is low due to high molecular weight and insolubility.
Mobility in Soil: Expected to be immobile; will remain at site of release.
Other Adverse Effects: Material contributes to overall waste plastic burden in environment.
Marine Pollutant: Not classified as marine pollutant by IMDG.
13. Disposal Considerations
Waste Disposal Methods: Reuse or recycle if possible; safely incinerate at facilities with pollution control or dispose in approved industrial landfill.
Contaminated Packaging: Clean or reuse containers whenever possible, otherwise send for controlled disposal.
Regulatory Considerations: Treat as non-hazardous solid waste according to local, regional, and national guidelines.
Special Precautions: Avoid burning in open air; avoid discharging into drains, soil, or aquatic environments.
14. Transport Information
UN Number: Not regulated
Proper Shipping Name: Chlorobutyl Rubber
Transport Hazard Class: Not classified as dangerous for transport.
Packing Group: Not applicable
Environmental Hazards: None specified under current regulations.
Special Precautions: Avoid sources of ignition, keep dry during transit.
15. Regulatory Information
Inventory Listing: Registered or pre-registered under most major national chemical inventories including TSCA (USA), EINECS (EU), DSL (Canada).
Workplace Regulations: Occupational exposure guidelines not established in the US, EU, or other major jurisdictions.
Labeling Requirements: No special hazard pictogram or warning; standard safety and handling recommendations apply.
Environmental Laws: Subject to plastic and polymer waste regulations in several regions; not classified as hazardous waste.
Other Notes: No substances of very high concern (SVHCs) per current REACH regulations are part of CIIR.
