Hot-melt glue stick

EVA is blended with other ingredients to make a glue-gun stick that sets on cooling.

Hot-melt glue stick, illustrative image

Material

EVA binder in the adhesive: EVA

Material selection rationale

Heat softening
Allows the formulated adhesive to flow when warmed.
Cohesive binder
Helps hold the cooled adhesive together.
Physical setting
The warmed adhesive flows onto a surface and gains strength as it cools. Ordinary EVA hot melt does not need a new monomer polymerisation to set.

How it becomes a product

  1. Blend the adhesive: EVA is mixed with selected tackifying resins, waxes and stabilisers.
  2. Form the stick: The blend is shaped into rods, cooled and cut to the required length. The blended adhesive is shaped as a stick for the applicator; reheating changes flow, while the binder, tackifier and wax remain distinct ingredients.

Preparation routes

Ethene and vinyl acetate route

Addition copolymerisation. Both monomers add through their carbon–carbon double bonds to form a chain containing ethene-derived and vinyl-acetate-derived units. Both double bonds participate, while acetate groups stay attached to the vinyl-acetate-derived segments. Changing their proportion changes flexibility without a separate PVC-style plasticiser.

Industrial initiators and reaction controls support chain growth. Foaming agents, adhesive waxes and tackifiers are added in later product-formulation steps. Neither the foam gas nor an adhesive tackifier belongs in the required monomer pair.

  1. EVA product general extrusion guideCelanese
  2. Ateva ethylene vinyl acetate copolymersCelanese

From ethene and ethanoic acid to vinyl acetate

  1. Ethene + Ethanoic acid + Oxygen → Vinyl acetate

    Ethene, ethanoic acid and oxygen react in a catalytic gas-phase process to make vinyl acetate. Unreacted ethene and acid are recovered, and the monomer is refined. The product retains a polymerisable vinyl group alongside its ester group. It is chemically distinct from ethyl ethanoate, which has a saturated ethyl group.

  1. Vinyl acetate monomer: reaction, feedstock recovery and refiningLOTTE INEOS Chemical
  2. Vinyl acetate monomerCelanese

Sources

  1. Glue sticks: EVA, resin and paraffinHögert Technik
  2. EVA product general extrusion guideCelanese