Polyurethane reactive hot melt with long pot life under high heat

Abstract

Moisture-reactive hot melt adhesive compositions are disclosed that are prepared from a combination comprising a polyisocyanate, a polyol, an MA-SCA acid, one or both of an inorganic filler or an organosilane, optionally a thermoplastic polymer, and optionally one or more additives. Useful polyols include poly(hexanediol adipate), polyester diols having the structure of Formula 1 or Formula 2, and combinations thereof. Formula 1 is: H—[O(CH2) m OOC(CH2) n CO] k -O(CH2) m -OH, where m and n are each even integers, m+n=8, m and n are each independently selected from 2, 4, or 6, and k is an integer from 9 to 55, and the polyol of Formula 1 has a number average molecular weight of about 2,000 to about 11,000. Formula 2, polycaprolactone polyol, is: HO-[(CH2)5COO] p -R1-[OOC(CH2)5] q -OH; where R1 is an initiator such as 1,4'-butanediol, 1,6'-hexanediol, or ethylene glycol, p is an integer from 0 to 96, q is an integer from 0 to 96, p+q=16 to 96, and the polyol has a number average molecular weight of about 2,000 to about 11,000.

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