Bostik, Inc.

Walter Rath

Heinz G Gilch

Herbert Bauer

Use Schumann

Karsten Seitz

A moisture-curing hot-melt polyurethane adhesive foam comprising isocyanate-terminated polyurethane prepolymers based on polyester or polyether and having a melting point of 40.degree. to 60.degree. C. or a glass transition point above room temperature, melted together, optionally with a nucleating agent and/or a surfactant, treated with an inert gas under pressure and released in ambient pressure is allowed to cure as a foam whereby a cure rate is achieved of at least ten times that of the composition when not foamed; extremely rapid cure rates are achieved and thick bond lines are readily obtained.

Moisture-curing, hot-melt polyurethane adhesive compositions

A quick-setting, moisture-curing hot-melt polyurethane composition having a first polyether-based polyurethane prepolymer having a Tg above room temperature and a second polyurethane prepolymer with a Tg below room temperature, the first prepolymer being prepared from a low molecular weight polyether; preferably the second prepolymer is also polyether based and prepared from a high molecular weight polyether.

Moisture-curing, polyurethane hot-melt compositions

A moisture-curing hot-melt composition comprising at least one isocyanate-terminated polyurethane prepolymer has improved sag-resistance while retaining high extrudability and is characterised in that the composition includes 1-17 wt %, preferably 3-6 wt %, of hydrophobic, siloxane-coated, fumed silica. Especially effective polyurethane hot-melt adhesive compositions are prepared containing 4-5 wt % of the hydrophobic, siloxane-coated fumed silica.

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Oberursel, Germany

Walter Rath