Modified guayule resin/soy protein blends for bio-based adhesives, associated methods for forming same, and associated structures including such adhesives

A method for forming an adhesive composition, comprising:

• forming a base-solvent modified guayule resin from an unmodified guayule base resin, with the unmodified base resin obtained in a rubber extraction process of guayule at solvent removal temperatures ranging from 104 to 166 degrees Celsius;
• mixing soy protein with said base-solvent modified guayule resin;
• and
• mixing an unmodified guayule base resin with the soy protein and the base-solvent modified guayule resin,
• wherein the unmodified guayule base resin is included in the adhesive composition in an amount ranging from 0.1% to 50% by weight of the total weight of the soy protein, and wherein said base-solvent modified guayule resin is formed by:
• forming a resin mixture by mixing the unmodified guayule base resin with a solvent mixture, the solvent mixture comprising acetone;
• mixing a base with the resin mixture;
• reacting the base with the guayule base resin within the resin mixture via a saponification process in the resin mixture, and
• extracting a bottom phase of the base-solvent modified guayule resin in acetone.