Hydroxyl-containing liquid polymers and adhesives made therefrom
AssigneeThe B. F. Goodrich Company
InventorWilliam N. Schenk
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Abstract
This invention relates to a low viscosity hydroxylated liquid polymer having polymerized therein a mercaptan compound containing hydroxyl and/or carboxyl group(s) in an amount sufficient to reduce viscosity and provide low peel property on the order of 10 to 25 ounces without significantly lowering the adhesive properties thereof, to a removable, low peel adhesive which is a reaction product of the liquid polymer and an isocyanate prepolymer, and to a substrate having deposited thereon said adhesive. The removable adhesive produces a clean 180.degree. peel while maintaining good tack and shear and due to its low viscosity, it can be processed at 100% solids, i.e., without any solvent.
Claims28
Hydroxylated liquid polymer composition comprising at least one alkyl acrylate liquid polymer containing polymerized therein a mercaptan compound containing hydroxyl and/or carboxyl group(s), or a mixture of such mercaptan compounds, said hydroxylated liquid polymer having about 1.4 to about 6 hydroxyl groups per molecule, and amount of said mercaptan compound being sufficient to reduce viscosity of said liquid polymer without significantly lowering adhesive properties thereof.
An adhesive composition for pressure-sensitive tape with low peel property comprising a reaction product of a hydroxylated liquid polymer and an isocyanate prepolymer;
- the hydroxylated liquid polymer is a reaction product comprising at least about 65 weight percent of at least one alkyl acrylate containing both terminal and random hydroxyl functionality with 3 to 10 carbon atoms in the alkyl group, a sufficient amount of a mercaptan compound to reduce viscosity of the liquid polymer without significantly lowering adhesive properties thereof, an average of about 1.4 to about 6 hydroxyl groups per molecule, and a molecular weight (M.sub.n) of about 1,000 to 6,000;
- the isocyanate prepolymer is a reaction product of a polyalkylene ether glycol or polyester glycol with an excess amount of an aromatic diisocyanate, the prepolymer has molecular weight of about 800 to about 3,000, the aromatic diisocyanate contains 8 to about 24 carbon atoms;
- and the ratio of hydroxyl equivalents to free isocyanate equivalents is from about 0.7/1 to about 4.5/1.
A substrate having deposited thereon an adhesive composition comprising a reaction product of a hydroxylated liquid polymer and an isocyanate prepolymer;
- the hydroxylated liquid polymer comprising at least about 65 weight percent of at least one alkyl acrylate containing both terminal and random hydroxyl functionality and 3 to 10 carbon atoms in the alkyl group, a sufficient amount of a mercaptan compound to reduce viscosity of the hydroxylated liquid polymer without significantly lowering adhesive properties thereof, an average of about 1.4 to about 6 hydroxyl groups per molecule, and a molecular weight (M.sub.n) of about 1,000 to 6,000;
- the isocyanate prepolymer is a reaction product of a polyalkylene ether glycol or polyester glycol with an excess amount of an aromatic diisocyanate, the prepolymer has molecular weight of about 800 to about 3,000, the aromatic diisocyanate contains 8 to about 24 carbon atoms;
- and the ratio of hydroxyl equivalents to free isocyanate equivalents is from about 0.7/1 to about 4.5/1.
Dependencies are inferred from the claim text.