Product

A Plastisol is a stable colloidal dispersion of ultra-fine Polyvinyl Chloride (PVC) paste resin particles (typically 0.1–2.0 µm) suspended in a liquid plasticizer — most commonly DINP (Diisononyl Phthalate) or DEHP — at a typical plasticizer concentration of around 86% by weight. At ambient temperature, the PVC particles remain discrete and the mixture behaves as a flowable, viscous liquid, since the plasticizer has negligible solvating power at room temperature.

Curing (Gelation & Fusion)

When heated to approximately 170–190 °C (338–374 °F), the plasticizer begins to solvate the PVC particles, causing them to swell and absorb the surrounding plasticizer. As temperature rises further, the particle boundaries break down and the mass fuses into a continuous, homogeneous polymer network — a process known as gelation and fusion, collectively referred to as curing. Once cooled below approximately 60 °C (140 °F), the fused mass solidifies into a flexible, permanently plasticized, dimensionally stable solid. The degree of flexibility of the final product is directly controlled by the plasticizer-to-resin ratio.

Key Processing Characteristics

• Viscosity is a critical formulation parameter, controlled by particle size distribution, plasticizer type, and the addition of viscosity modifiers or fillers (e.g., calcium carbonate, barium sulfate)
• Shelf life must be managed carefully, as partial solvation at ambient temperatures causes viscosity drift over time
• Heat stabilizers (e.g., calcium-zinc, organotin compounds) are essential additives to prevent thermal degradation of the PVC during curing
• Foaming agents can be incorporated to produce expanded/foamed Plastisol products

Applications

Plastisol's unique liquid-to-solid transformation makes it suitable for a wide range of processing methods and end products:

• Dip coating & slush molding — automotive parts, gloves, tool handles, toys
• Spread coating & calendering — artificial leather, tarpaulins, wallcoverings, flooring
• Screen printing inks — textile and garment printing (Plastisol inks)
• Rotational and injection molding — soft plastic fishing lures (soft-plastic bait)
• Solid Rocket Propellant binders — used as a binder matrix in composite solid rocket boosters
• Polymer clays — hobby and modelling compounds (e.g., FIMO, Sculpey)
• Foam seals and gaskets — automotive and industrial sealing applications