Technical Specifications
| Property | Unit | Typical Value | Test Method |
|---|---|---|---|
| Appearance | Light yellow transparent viscous liquid | Visual | |
| Density at 20 °C | kg/m³ | 940 | ASTM D4052 |
| Viscosity at 100 °C | mm²/s | 650 | ASTM D445 |
| Flash Point | °C | >180 | ASTM D93 |
| Acid Value | mgKOH/g | 115 | ASTM D664 |
| Mechanical Impurities | % | 0.01 | ASTM D473 |
| Water | % | 0.01 | ASTM D95 |
* Typical values from batch production. Batch-specific COA available on request.
Technical content reviewed by the CheMost additives team · Specifications last reviewed
Molecular Structure
Molecular structure · polyisobutylene succinic anhydride
Polyisobutenyl succinic anhydride — a polyisobutylene (PIB) chain bearing a succinic-anhydride head group
An amphiphilic molecule: the oleophilic PIB tail anchors in oil while the polar succinic-anhydride/acid head sits at the water interface — the basis of its emulsifying action and of succinimide-dispersant synthesis.
What Is Polyisobutylene Succinic Anhydride (PIBSA)?
CheMost-PIBSA is a highly active polyisobutylene succinic anhydride (PIBSA) — an oil-soluble, ashless emulsifier built from a polyisobutylene (PIB) chain carrying a reactive succinic-anhydride head group. It is made from highly active PIB by a special chlorine-free process, leaving no chlorine and very few by-products, and is supplied as a light-yellow, transparent viscous liquid.
PIBSA is made by reacting polyisobutylene with maleic anhydride (the thermal “ene” reaction). Using highly active (high-vinylidene) PIB and a thermal rather than a chlorination route gives high conversion and avoids the residual chlorine that older routes leave behind — an important quality and environmental advantage. The result is an amphiphilic molecule: the long PIB tail is oleophilic (oil-loving) while the polar succinic-anhydride/acid head is drawn to water, which is exactly what makes PIBSA both a surfactant and the building block for a whole family of additives.
As an emulsifier — its primary role here — PIBSA is valued in metalworking fluids for good emulsification, hard-water resistance and low foaming. The product’s acid value of 115 mgKOH/g reflects the level of succinic-anhydride functionality available to do that interfacial work and to react further into derivatives.
How PIBSA Works
Amphiphilic by design
The oleophilic PIB tail sits in the oil while the polar succinic-anhydride/acid head orients toward water — the molecule straddles the oil/water interface.
Stabilises the emulsion
By lowering interfacial tension and forming a protective layer around droplets, PIBSA keeps oil and water dispersed as a stable emulsion — the goal for soluble cutting oils and metalworking fluids.
Hard-water resistant, low foam
The data sheet highlights tolerance to hard water (calcium/magnesium ions) and low foaming — two practical demands of a working metalworking-fluid emulsion.
A reactive anhydride head
The succinic-anhydride group is also a chemical handle: react it with a polyamine and PIBSA becomes a PIB succinimide dispersant — the basis of its second role.
PIBSA’s Two Roles — Emulsifier and Dispersant Precursor
The same amphiphilic structure gives PIBSA two distinct industrial jobs, and it is worth being clear which one you are buying it for.
| Role | How PIBSA is used | Typical systems |
|---|---|---|
| Emulsifier (this page’s focus) | Used as-is — the amphiphile stabilises an oil/water emulsion | Soluble & semisynthetic metalworking fluids, cutting oils, rust preventives |
| Dispersant precursor | Reacted with a polyamine → a PIB succinimide ashless dispersant | Engine-oil dispersant manufacture |
As an emulsifier, PIBSA is added directly to a metalworking-fluid concentrate, where it does the interfacial work of holding oil and water together. As a dispersant precursor, the succinic-anhydride head is reacted with a polyamine — the primary amine forms a cyclic imide — to make the polyisobutenyl succinimide dispersants that suspend soot and sludge in engine oils. PIBSA is also the basis of amphiphilic corrosion inhibitors that protect metal at the water interface. This page covers the emulsifier grade; the chlorine-free, highly active chemistry is what makes it effective across all of these.
Applications
CheMost-PIBSA is used as the emulsifier (or reactive intermediate) in formulations targeting the duties below:
Metalworking fluids
The primary use: emulsifier for soluble and semisynthetic metalworking fluids, giving good emulsion stability, hard-water resistance and low foam.
Cutting & soluble oils
Emulsification of cutting and soluble oils that are diluted with water at the point of use, where a stable, fine emulsion is essential.
Rust preventives
As an amphiphilic film-former, PIBSA-type chemistry helps protect metal surfaces against corrosion in aqueous metalworking and rust-preventive fluids.
Dispersant manufacture
As the reactive intermediate for PIB succinimide ashless dispersants — reacted with polyamines rather than dosed as-is.
Finished-fluid performance approvals belong to the fully formulated product, not to an individual additive component.
Treat Rate
The data sheet specifies the product but not a per-application dosage, so the figures below are indicative — derived from the chemistry and our formulating experience — and should be confirmed on your emulsion system.
First-order estimate. As an emulsifier, PIBSA is a significant component of a metalworking-fluid concentrate — typically on the order of a few up to ~15 wt% of the concentrate, which is then let down in water at the point of use (often to a few percent oil). The level is set by the oil/water ratio, the base oil and the water hardness; emulsion stability is a balance of all three, not just emulsifier quantity.
When PIBSA is instead used as a dispersant precursor, it is not dosed at a treat rate at all — it is reacted with a polyamine in a defined anhydride-to-amine ratio. Either way, the right level is confirmed on the finished system.
Treat rates are indicative, not fixed dosages. CheMost can provide formulation and emulsion-stability support on request.
Formulating With PIBSA — Complementary Additives
Foam inhibitors / defoamers
A metalworking emulsion must stay low-foaming in use; PIBSA’s own low-foam character is paired with a defoamer to keep entrained air and surface foam under control.
Ashless dispersants
PIBSA is the precursor to PIB succinimide dispersants — reacted with a polyamine to build the ashless dispersant family used in engine oils.
Rust & corrosion inhibitors
In aqueous metalworking fluids, PIBSA-type amphiphiles support corrosion protection at the metal/water interface alongside dedicated rust inhibitors.
Co-emulsifiers
PIBSA is often used with other emulsifiers (such as petroleum sulfonates) to tune the emulsion’s droplet size, stability and hard-water tolerance.
Documentation, Qualification & Regulatory Support
Standard documentation — Certificate of Analysis (COA, per shipment), Technical Data Sheet (TDS) and Safety Data Sheet (SDS, GHS/CLP) — is provided. The full TDS is available on request rather than as a public download. Additional support is available on request:
Regulatory documentation
REACH, TSCA and country-specific market-registration documentation support available on request.
Third-party inspection
SGS / Intertek / BV pre-shipment inspection can be arranged on request.
Custom grades & packaging
Custom PIB molecular weight, functionality and packaging on request.
Formulation support
Emulsion-stability and treat-rate guidance from our technical team.
Packaging & Supply
CheMost-PIBSA is stocked and shipped worldwide, with a typical lead time of 1–15 days and a 36-month shelf life at ambient temperature. Samples and quotations are answered within 12 hours.
Packaging
170 kg metal drum · 900 kg IBC tank · ISO tank.
Minimum order
By drum or IBC — contact us for your quantity.
Incoterms
FOB · CIF · EXW, to suit your freight arrangement.
Loading ports
All major Chinese ports.
Frequently Asked Questions
What is polyisobutylene succinic anhydride (PIBSA)?
It is an oil-soluble, ashless surfactant made by reacting polyisobutylene (PIB) with maleic anhydride, giving a PIB chain with a reactive succinic-anhydride head. The oleophilic PIB tail and polar anhydride head make it both an emulsifier (for metalworking fluids) and the precursor to PIB succinimide dispersants. CheMost-PIBSA is made by a chlorine-free process with very few by-products.
Is PIBSA an emulsifier or a dispersant?
Both, depending on how it is used. Used as-is, PIBSA is an emulsifier that stabilises oil/water emulsions in metalworking fluids. Reacted with a polyamine, the anhydride head converts it into a PIB succinimide ashless dispersant for engine oils. This page covers the emulsifier grade.
Why does “chlorine-free” matter?
Older PIBSA routes used chlorine and left residual chlorine in the product. CheMost-PIBSA is made by a thermal process from highly active PIB, so it is chlorine-free with very few by-products — better for product quality, downstream performance and environmental/regulatory profile.
What does the acid value of 115 mean?
The acid value (115 mgKOH/g, ASTM D664) reflects how much succinic-anhydride/acid functionality the product carries — the active head groups that do the emulsifying work and that react to form derivatives. A higher functionality generally means a more active emulsifier and a more reactive intermediate.
How is it supplied, and how much do I use?
It is supplied as a light-yellow viscous liquid in 170 kg drums, 900 kg IBCs and ISO tanks, with a 36-month shelf life. As an emulsifier it is a few up to ~15 wt% of a metalworking-fluid concentrate, set by the oil/water ratio and water hardness; the exact level is confirmed on your system. Samples and quotations are answered within 12 hours.