Typical Formulation Ingredients
Phase
Ingredient
Parts by weight
A
Polybutadiene resin (Poly BD® R45HTLO or Poly BD® LF-3, Sartomer)
A
Terpolymer, EVA-HEA (OREVAC® 9402, Atofina)
A
Tackifier (Kristalea F-85 from Hercules or Cray Valley)
A
[ISONATE™ 125 M, Dow Chemical/OH]1
A
[ISONATE™ 125 M, Dow Chemical/OH]2
A
Dodecanol / whole formulation
Typical Properties
Relativity low melt viscosity compared with a non-reactive adhesive
Application temperature is a low 130°C
Good resistance to peel on cotton
Resulting Properties
A moisture-cure hot melt formulation based on EVA- HEA (hydroxyl containing EVA resin) and Poly bd® is described in the formulation above. Using polybutadiene polyol will provide much better hydrolytic stability than other conventional polyols (e.g., polyester or polyether).
Often additives are not required to provide flexibility or toughness. Polyurethanes have the capability of providing these properties through manipulation of the resulting molecule by proper choice of isocyanate and polyol. However, additives are used mainly to stabilize the adhesive relative to moisture, oxidation, UV, etc.