Sandwich panels with crosslinked foamed polyethylene core - are flame treated for surface activation prior to adhesive bonding of facing layers

摘要

Sandwich panels are made by flame treating the surface of a crosslinked polyethylene core under oxidising conditions, applying an adhesive to the treated surface, applying the outer layer and pressing. Pref. the adhesive used is a heat activatable adhesive film e.g. of modified ethylene copolymer and pressing is carried out at a temp. at which the adhesive film softens or melts. Pref. before the flame treatment the surface of the polyethylene core is provided with ridges 1.5-2.0 mm. deep and 0.5-1.0 mm. wide, or with slots 2.0-4.0 mm. deep. USE/ADVANTAGE - The flame treatment activates the surface of the polyethylene core and allows self supporting composite sandwich panels to be prepd. having bonded outer layers of metal, plastics, fibre reinforced polyester or epoxy resin etc. The panels have good heat-, sound- and vibration insulating properties and are usefule.g. for construction of delivery vans, etc.