PVC Dispersing Agent | Specialty Applications

PVC Dispersing Agent: Specialty Applications

SEKISUI’s Selvol™ polyvinyl alcohol (PVOH) resin has long served as a primary dispersing agent in polyvinyl chloride (PVC) suspension polymerization. This is the process behind the majority of the world’s PVC resin production.

As a protective colloid, Selvol PVOH governs how vinyl chloride monomer droplets form and stabilize in the aqueous phase. In turn, this shapes the resulting PVC particles’ porosity, bulk density, particle size distribution and thermal characteristics.

Selvol PVOH 540 has become the industry standard for this role, with a decade-plus track record PVC producers depend on.

For formulators who need more targeted control, Selvol PVOH E 605, E 635 and E 640 offer varying degrees of hydrolysis and solution viscosity. This gives you a lever for fine-tuning particle morphology without reworking an entire polymerization recipe.

Note. PVOH also acts as a stabilizer in emulsion polymerization for different resin systems. Learn more about PVOH in emulsion polymerization.

Why Formulators Choose Selvol PVOH as a PVC Dispersing Agent

As a leading PVC dispersing agent, Selvol PVOH delivers the consistency and grade flexibility you rely on to control resin particle properties batch after batch:

Proven, consistent performance across decades of commercial PVC suspension polymerization
A grade for every target: varying degree of hydrolysis and viscosity across Selvol PVOH 540, E 605, E 635 and E 640
Direct influence over particle porosity, bulk density and particle size distribution
Validated performance data, including Selvol PVOH E 635 benchmarked in a K-67 formulation against market-standard products
Manufactured to tight ash and volatiles specifications for reliable lot-to-lot consistency
Backed by ISO-certified manufacturing in the U.S. and Spain and application support from SEKISUI’s Houston Technology Center

Learn more about the high-purity Selvol E PVOH line.

How PVOH Controls PVC Particle Formation

In suspension polymerization, vinyl chloride monomer is dispersed as droplets in water. Selvol PVOH adsorbs at the droplet surface to prevent coalescence as polymerization proceeds.

Two properties do most of the work:

Degree of hydrolysis. This controls how the polymer partitions at the droplet interface, influencing droplet stability and final particle porosity.
Solution viscosity (molecular weight). This shapes the strength of the protective layer around each droplet, influencing particle size distribution

Because formulators can influence these variables independently through grade selection, choosing the right Selvol PVOH grade allows you to dial in resin particle properties.

Download Selvol PVOH bulk handling guidelines, or learn more about PVOH solution preparation.

Where PVC Dispersing Agents Make a Difference

Get the dispersing agent right, and it shows up downstream in the PVC resin used across construction and industrial applications. These are few examples of that versatility:

Pipe and fittings. Pressure and non-pressure PVC pipe for water, sewer and drainage systems.
Window and door profiles. Rigid PVC and CPVC extruded profiles for construction.
Siding and other building products. Rigid PVC extrusion for exterior cladding.
Wire and cable insulation. Flexible PVC compounds for electrical applications.
Calendered sheet and flooring. PVC film and flooring products made via calendering.

That reach extends further than the resin itself. Porosity and bulk density affect plasticizer uptake and extrusion consistency. Thermal characteristics set during polymerization influence how the resin holds up under processing heat: a key factor for pipe and profile extrusion.

That’s why converters and compounders further down the supply chain feel the effects of dispersing agent selection as much as the resin producer does.