Vegetable oil-based pressure-sensitive adhesives

A method for making a pressure sensitive adhesive construct comprising:

• reacting (i) at least one epoxidized vegetable oil with (ii) a prepolymer or oligomer capped with a carboxylic acid group at both prepolymer or oligomer chain ends, or a branched prepolymer or oligomer with at least two of the prepolymer or oligomer branches and chain ends capped with a carboxylic acid group, wherein the carboxylic acid-capped prepolymer or carboxylic acid-capped oligomer is made from (a) an excess of dibasic acid reacted with (b) a glycidyl or an epoxidized compound having at least two epoxy groups, or a combination thereof;
• and
• forming on a backing substrate a pressure sensitive adhesive from the resulting reaction product.

A method for making a pressure sensitive adhesive composition comprising:

• (a) reacting (i) a dibasic acid with (ii) at least one agent to provide a prepolymer or oligomer capped with a carboxylic acid group at both prepolymer or oligomer chain ends, or a branched prepolymer or oligomer with at least two of the prepolymer or oligomer branches and prepolymer or oligomer chain ends capped with a carboxylic acid group, wherein the at least one agent comprises a diglycidyl ether, an epoxidized compound having at least two epoxy groups, or a combination thereof;
• and
• (b) reacting at least one epoxidized vegetable oil with the carboxylic acid-capped prepolymer or carboxylic acid-capped oligomer to produce a pressure sensitive adhesive composition.