Sulfurized isobutylene (SIB): core antiwear EP Additive of grease under high-load impact

The challenge of heavy load lubricant grease facing

The lubricant grease is stable under light loading or static conditions. Once it enters into the heavy loads and high-speed impact conditions, the problems arise

The oil film is forcibly squeezed out, leading to direct metal-to-metal contact.

The friction heat owing to friction will increase quickly, causing conventional additives to fail or even decompose.

The surface will appear microwelding and scoring appear, the equipment's service life reduces.

 

The physical film of traditional lubricant grease is easy to failure under extreme pressure, therefore, it needs the extreme pressure that can produce dynamic oil film, such as sulfur-, phosphorus, and nitrogen-based EP agents.

 

When discussing EP agents, sulfurized isobutylene (SIB) is indispensable.

 

Why is sulfurized isobutylene used in heavy‑duty industrial greases?

Sulfurized isobutylene is a high-sulfur EP antiwear additive. It contains active sulfur, which provides immediate protection when friction appears.

How does sulfurized isobutylene overcome the lubrication bottleneck under heavy-duty conditions?

 

Under low-load conditions: Active components adsorb onto metal surfaces, forming a chemical adsorbed film and a small amount of reaction film to reduce friction and maintain smooth operation.

Under medium-load conditions: As the load increases, friction heat activates deeper reactions, and generate high molecular weight friction polymers that attach on the metal surfaces, and eventually forming an organic iron compound film to prevent wear and friction.

Under heavy-load conditions: High shear and high temperatures cause the polymer decompose, while active sulfur reacts with iron and forms a dense iron sulfide reaction film to prevent seizure and failure.

Sulfiurized iso-butylene (SIB) lubricant EP additive deliver comprehensive extreme-pressure and antiwear protection for metals.

 

Core advantages of sulfurized isobutylene EP additive

High EP activity: Under high-speed impact, SIB can effective prevents the damage and sintering because of metal contact.

Good thermal stability: SIB is not easily to decompose at high temperatures, ensuring the grease long-term using under the heat-generating conditions.

Wide compatibility: SIB is compatible with various grease systems and affect grease consistency and stability.

Wide applications: SIB is widely used in gear oils, metalworking fluids, and greases, making it one of the most widely used EP additives in current grease formulations.

 

Active sulfur content – the key to quality differentiation

Chorus sulfurized isobutylene T321 recommended

The EP/antiwear performance of sulfurized isobutylene (SIB) is not only determined by sulfur content.

The proportion of active sulfur is the core indicator of product quality.

The product contains various sulfur-containing species with different activities: the higher the active sulfur content, the stronger the EP protection.

Chorus's sulfurized isobutylene T321 with high active sulfur content, is suitable for heavy‑load gear oils, greases, and other industrial lubricants, providing excellent EP and antiwear performance for metals.

 

In addition, we also offer high-performance copper corrosion inhibitors, mainly benzotriazole (BTA) corrosion inhibitors, tolyltriazole (TTA) inhibitors and their derivatives, which form protective films on copper and copper alloy surfaces to effectively prevent corrosion.

TTA-39 oil soluble metal deactivator: suitable for metalworking oils and lubricating oils.

 

We can supply superior sulfurized isobutylene EP antiwear additives and copper corrosion inhibitors.

Contact us for the latest quotations and product information.

Know more about sulfurized iso-butylene (ISO) additives.