Styrene-Butadiene Rubber CAS 9003-55-8

What is Styrene-Butadiene Rubber?

Styrene-butadiene rubber is the highest-volume synthetic rubber in the world, a copolymer of butadiene and styrene that replaced natural rubber in tyre tread during the Second World War and never gave the position back.

Two families exist. Emulsion SBR is polymerised in water with free radical initiation and is the commodity workhorse; solution SBR is made with organolithium catalysts and allows precise control of microstructure for high-performance tyres.

Grades are identified by the IISRP numbering system: the 1500 series is dry ESBR, the 1700 series is oil-extended, and so on.

Bound styrene content sets the balance between wet grip and rolling resistance, which is why tyre formulators specify it precisely rather than treating SBR as a single material.

Why SBR specifically

• Better abrasion resistance than natural rubber. Which is why it dominates passenger tyre tread.
• Consistent and controllable. Synthetic production gives uniformity that agricultural natural rubber cannot match.
• Tunable microstructure in SSBR. Vinyl content and styrene distribution can be set precisely for the rolling resistance and grip balance wanted.
• Cost-effective at volume. The largest-volume synthetic rubber, with a correspondingly mature cost base.

How Styrene-Butadiene Rubber is Manufactured

SBR is made by emulsion or solution copolymerisation of butadiene and styrene, with the route determining the control available.

• Monomer feed. Inhibited butadiene and styrene are the base monomers, with the ratio setting bound styrene content.
• Emulsion polymerisation. Cold ESBR is polymerised at about 5 °C in soap solution with a redox initiator, giving the 1500 and 1700 series.
• Solution polymerisation. SSBR is made in hydrocarbon solvent with organolithium initiators, allowing control of vinyl content and chain-end functionality.
• Oil extension. Aromatic, naphthenic or TDAE oil is added to the latex or cement for the oil-extended grades.
• Coagulation and finishing. Latex is coagulated, washed and dried; solution cement is steam stripped.
• Baling. The crumb is dried, baled at about 35 kg and wrapped in polyethylene film.

Typical Commercial Specification

Figures below are representative of a dry ESBR 1502 grade. Oil-extended and solution grades differ — tell us the grade number or the application and we will send the matching sheet.

Physical & Chemical Properties

Behaviour in the process

SBR behaves predictably in the mixing room, with a few points that affect compound design:

• Requires reinforcement. Unlike natural rubber, SBR does not strain-crystallise, so carbon black or silica reinforcement is essential for strength.
• Poor ozone resistance. Needs antiozonant and wax protection for outdoor service.
• Oil swell. Swells in hydrocarbons; unsuitable for oil contact applications where nitrile rubber belongs.
• Staining versus non-staining antioxidant. Staining types give better protection but discolour light-coloured goods.

SBR Types and Alternative Elastomers

SBR is bought by grade number, which encodes the polymerisation route, oil extension and antioxidant type.

Stated plainly: tyre compounds blend SBR, polybutadiene and natural rubber rather than choosing between them. SSBR earns its premium specifically where tyre label rolling resistance ratings are at stake.

Industries We Supply Styrene-Butadiene Rubber To

SBR serves tyres above all, with footwear, technical goods and adhesives behind.

Where Styrene-Butadiene Rubber is Used

Tyre manufacture takes the majority of SBR, with footwear and technical goods sharing most of the rest.

In tyre tread compounds

SBR is blended with polybutadiene and reinforced with carbon black or silica. Bound styrene content sets the glass transition and therefore the balance between wet grip and rolling resistance — higher styrene improves grip but costs fuel economy. Silica-reinforced SSBR compounds with coupling agents are the standard route to low rolling resistance tread.

ESBR versus SSBR

Emulsion SBR is cheaper and processes easily, but its microstructure cannot be controlled. Solution SBR allows vinyl content, styrene distribution and chain-end functionality to be set, which is what makes modern low-rolling-resistance tread possible. The premium is real and so is the performance difference.

Quality Control & Testing

Every lot is released against a batch-specific Certificate of Analysis with the grade's defining properties, so your incoming inspection can release against the actual material.

• Mooney viscosity — ML (1+4) at 100 °C, the primary processing indicator.
• Bound styrene content — setting the glass transition and compound properties.
• Volatile matter — confirming drying and storage condition.
• Ash and soap content — residues from the emulsion process affecting cure.
• Oil content — for oil-extended grades, confirming the extension level.
• Antioxidant type and level — staining or non-staining, which matters for light goods.

Common Process Problems & Likely Causes

When SBR causes trouble, it is usually Mooney drift, cure variation or contamination. This table is the shortcut our technical desk works through before anyone opens a complaint file.

Packaging, Storage & Shipping

• Standard packing. 35 kg bales wrapped in polyethylene film, palletised or in wooden crates and containers.
• Storage. Cool, dry, covered warehousing away from direct sunlight and heat sources.
• Temperature. Below 30 °C where possible; warm storage causes bales to deform and stick.
• Stack height. Limit stacking; bale deformation under load is the usual physical complaint.
• Ozone protection. Keep away from electrical equipment generating ozone, which attacks unprotected rubber.
• Segregation. Keep grades clearly separated; bales are visually similar across grades.
• Shelf life. Typically 12 to 24 months in proper storage; Mooney viscosity may drift slowly.
• Transport classification. Not classified as dangerous goods for transport.

Hazards & Safe Handling

SBR is an inert polymer with no significant health hazard in normal handling. The practical concerns are manual handling of bales, mixing dust and fume from hot processing.

• Inert in normal handling. Not classified as hazardous. Bales present no chemical risk in storage or transport.
• Manual handling. 35 kg bales are a significant ergonomic hazard; use mechanical handling where possible.
• Mixing fume. Internal mixer and mill operations generate rubber process fume; ventilation and extraction are required.
• Hot processing. Mills, mixers and curing presses present burn and entrapment hazards; guarding is essential.
• Compound ingredients. The curatives, oils and fillers added in compounding carry their own hazards; the compound SDS governs.
• Environment. Inert in the environment but persistent; contain waste and use established rubber recycling routes.

Regulatory & Compliance Notes

SBR is unregulated for transport, with tyre labelling and extender oil regulation affecting its use. The notes below are orientation rather than legal advice.

• GHS classification. Not classified as hazardous.
• Transport. Not classified as dangerous goods. Standard packaged cargo documentation applies.
• Extender oil regulation. High-PAH aromatic extender oils are restricted in the EU for tyres; TDAE and MES oils are the compliant alternatives.
• Tyre labelling. EU and other tyre labelling regimes rate rolling resistance and wet grip, which drives SSBR adoption.
• REACH and inventories. Polymers are exempt from REACH registration, though monomers, oils and additives are not.
• Food contact. Specific grades for food contact rubber goods require separate compliance documentation.

We Supply Styrene-Butadiene Rubber Worldwide

Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship Styrene-Butadiene Rubber from India and from partner sources to customers across Asia, Europe, the Middle East, Africa, and North and South America, handling the export documentation, transport paperwork and freight so the material arrives ready to use.

• Incoterms. EXW, FOB, CIF, CFR and DAP quoted to suit your purchasing terms and freight arrangements.
• Ports. Regular shipments through Nhava Sheva (JNPT) and Mundra, with other ports arranged where routing and cargo rules allow.
• Documentation. Commercial invoice, packing list, certificate of origin, COA, SDS and the transport declaration issued as a complete set.
• Flexible volumes. From a pallet of bales up to repeat bulk shipments on a supply contract.
• Supply continuity. Because we are independent of any one producer, a plant turnaround or a shipping disruption at one source does not have to become your stock-out.

Buying Styrene-Butadiene Rubber from Chelora

We are an independent sourcing and supply partner. For SBR that means settling three things at enquiry: the IISRP grade number or the performance target, whether oil extension and which oil type is required, and whether staining or non-staining antioxidant suits your goods.

• Documentation on every lot. Batch-specific COA (Mooney viscosity, bound styrene, volatiles, ash), plus SDS and the full transport paperwork.
• Analysis before commitment. Representative analysis shared ahead of a commercial order so your lab can qualify the material.
• Quantities. From a pallet of bales through to full bulk shipments on contract supply.
• Grade matching. ESBR or SSBR grade at the Mooney viscosity, bound styrene and oil extension your compound requires.
• Inspection. Independent third-party inspection available at loading when the contract requires it.
• Related products. Polybutadiene Rubber, 1,3-Butadiene, Styrene Monomer and other feedstocks alongside Styrene-Butadiene Rubber from one supplier.

How ordering works

• Send the enquiry. Product, grade or purity, quantity, destination port and the Incoterm you buy on. If you have a spec sheet, attach it — it saves a round trip.
• We quote. Price, lead time, packing format and a sample COA, normally within one working day.
• Qualify the supply. For first orders or critical applications, we share the analysis and handling documentation so your technical and safety teams can sign off before you commit.
• Confirm the order. Proforma invoice issued; payment terms agreed against the volume and the relationship.
• Allocation and QC. Material allocated and released against a batch-specific COA, with an independent inspection where the contract calls for it.
• Ship and document. Filled, labelled and loaded with the full export document set, and tracked through to arrival.

Related Products

Buyers of SBR often source other elastomers alongside it — polybutadiene, nitrile and butyl rubber are commonly bought on the same programme.