The most common polymers used as coating materials are plastisols, latex, neoprene, polyurethane and epoxy resins. A noteworthy characteristic of polymers is that the polymer mixture must be readily available in liquid form at room temperature without requiring additional processing. Additionally, before a liquid polymer can be considered for use in dip coating and dip molding processes, it must be viscous enough to resist running away from the mold surface; therefore, the polymer will settle on the surface until it solidifies.
Plastisol
Plastisols are the most commonly used polymers in dip molding and dip coating processes. It consists of fine polyvinyl chloride (PVC) resin suspended in a liquid plasticizer. When heated, it solidifies into a soft, stretchy and rubber-like material as it cools. Plastisol coatings are known for their toughness, excellent corrosion resistance and impact resistance. It has a high dielectric strength, which makes it suitable for electrical applications. Colorants are added to customize the look of the final product.
Emulsion
Latex is an emulsion of very small polymer particles (30-40% of which are rubber particles). It is the raw material for rubber production and may be natural or synthetic. This polymer is readily available and non-toxic. However, according to some studies, some people can develop allergic reactions once it degrades into powder, reducing its popularity.
Neoprene
Neoprene is polymerized from neoprene and is a latex substitute. It is known for its chemical resistance and flexibility.
Polyurethane
Polyurethane is composed of urethane groups linked by urethane. It is known for its flexibility and high elasticity to deformation.
Epoxy resin
Epoxy resin is a thermoset polymer, once the polymer chains are cross-linked, forms a high-strength, chemical- and heat-resistant coating.