Polyethylene Wax and EVA

Ethylene vinyl acetate is the most commonly used polymer in hot melt adhesive formulations for packaging and nonwovens today. Polyethylene wax and EVA-based hot melt adhesive formulations exhibit properties in terms of tack, viscosity, density, and melt stability, with varying results depending on the formulation and other components.

Relevant test results show that polyethylene polymers have similar properties to EVA when used as base polymers in hot melt adhesives. And in some ways better than EVA.

Viscosity

Hot melt adhesive formulations based on polyethylene wax have lower melt viscosities than formulations based on EVA. This allows for easier application to the substrate and better and more thorough wetting of the surface.

density

Polyethylene wax based hot melt adhesives are more compatible than EVA based adhesives and can be used in repulping processes. Adhesives with densities outside the range are easier to separate with centrifugal cleaners. This makes them more suitable for use in recyclable packaging.

Melt stability

Polyethylene polymers are much more stable in the melt phase than EVA polymers. This may be due to the simplicity of the polymer structure.

When used as the base polymer, polyethylene polymers can improve adhesion properties compared to EVA. Additionally, PE waxes can be added to EVA-based hot melt adhesive formulations to improve melt stability, adhesion, and cure time. Often, all that is required to produce a continuous package of hot melt adhesives is the right polyethylene polymer, tackifying resin and antioxidant.