Key takeaways
- PVC is described first by process, not structure — suspension (S-PVC) and emulsion (E-PVC) are the same polymer but cannot substitute for each other.
- S-PVC has large porous granules (100–150 µm) that absorb plasticiser fast — it dominates rigid extrusion (window profiles, pipe, fittings, siding) and most flexible compound.
- E-PVC has tiny dense particles (0.1–2 µm) that disperse into a plastisol paste for vinyl flooring, dipped parts, artificial leather and coatings — none of which work with S-PVC.
- Specify the process plus K-value (S-PVC) or paste viscosity in mPa·s (E-PVC), pipe class, and stabiliser-system tolerance — the EU has moved off lead, parts of Asia have not.
Most other commodity polymers are described first by their molecular structure. PVC is described first by how it was made. Suspension PVC (S-PVC) and emulsion PVC (E-PVC) are chemically the same polymer, but the particle morphology that comes out of the reactor is so different that the two cannot substitute for each other in their main applications.
Suspension PVC is polymerised in droplets of monomer suspended in water. The result is a porous granule, typically 100–150 microns across. That porosity matters: it lets the granule absorb plasticiser and stabiliser quickly during dry-blending, which is why S-PVC dominates the rigid extrusion segment — window profiles, pipe, fittings, siding — and most of the flexible compound segment too.
S-PVC is graded by K-value, which is a measurement of average molecular weight. K65–67 is typical for pipe; K57–60 for injection mouldings; K70+ for cable insulation. Different K-values are not interchangeable. A pipe extruder set up for K67 will not run K57 cleanly.
Emulsion PVC is polymerised in much smaller droplets stabilised by surfactant. The dried particles are 0.1–2 microns. Those tiny particles disperse easily in plasticiser to form a plastisol — a paste that can be spread, dipped, sprayed, or rotationally cast and then heated to fuse.
Plastisols are how vinyl flooring is made. They are also how dipped automotive parts, artificial leather, and the soft-touch coating on wallpaper are made. None of those processes work with S-PVC. The particles are too large to disperse cleanly.
- Process (S-PVC or E-PVC — never just "PVC")
- K-value for S-PVC; viscosity in mPa·s for E-PVC paste resin
- Pipe class or end-application context
- Stabiliser system tolerance — the EU has moved off lead, parts of Asia have not
- Origin preference and Incoterms
Many global producers run both processes side-by-side. Most regional producers run only one. That is why pricing for S-PVC and E-PVC drifts in different directions during tight markets, and why a substitution offer from one process to the other is almost always a sign of a confused supplier.
Frequently asked
Questions on the desk
What is the difference between suspension and emulsion PVC?
They are the same polymer made by different processes, with different particle morphology. Suspension PVC (S-PVC) forms large porous granules (100–150 µm) suited to dry-blending and rigid/flexible extrusion. Emulsion PVC (E-PVC) forms tiny dense particles (0.1–2 µm) that disperse into a spreadable plastisol paste.
Which PVC is used for vinyl flooring?
Emulsion PVC (E-PVC), as a plastisol — a paste that is spread, dipped, sprayed or cast and then heated to fuse. Dipped automotive parts, artificial leather and soft-touch coatings use the same route. S-PVC particles are too large to disperse cleanly for these.
What is K-value in PVC?
K-value is a measure of average molecular weight for suspension PVC. K65–67 is typical for pipe, K57–60 for injection mouldings, and K70+ for cable insulation. Different K-values are not interchangeable — a line set up for K67 will not run K57 cleanly.
Can suspension and emulsion PVC be substituted for each other?
No. Their particle morphology serves different processes, and their pricing even drifts in different directions in tight markets. A substitution offer from one process to the other is almost always a sign of a confused supplier.
General market commentary from the OmniaStrata desk, provided for information only. It is not legal, financial, tax, or trading advice, and it is not an offer or a commitment to any terms. Figures such as price ranges, spreads, financing costs, and credit periods are illustrative market context, not OmniaStrata's rates or terms. Actual contract terms — including price, payment instrument, credit, insurance, and Incoterms — are agreed in writing on a per-transaction basis and at OmniaStrata's discretion. Market conditions change; figures reflect the publication date.