Bio-based and sustainable pressure sensitive adhesives (PSAs) were produced from epoxidized soybean oil (ESO) and a novel long-chain dibasic acid (PD) with a number average molecular weight (Mn) > 3.000 Da. PDs were obtained by reacting sebacic acid (SA) with a cardanol-based epoxy resin using unbalanced equivalent acid/epoxy ratios (R) of 1.23, 1.5 and 1.76 and through environmentally sound procedures without the use of catalysts or volatile solvents. Additionally, control PSAs were developed using ESO and SA. All PSAs exhibited glass transition temperature (Tg) values lower than −20 °C, suitable for room temperature applications, and met the Dahlquist criterion. Among the obtained PSAs, the formulation with the PD synthesized with R = 1.5 presented superior pressure-sensitive properties (tack forces of 2.4 N/cm2, shear strength of 430 min, and 180° peel strength of 4 N/cm) compared to those of measured commercial PSAs, under similar conditions. This study introduced an innovative approach to producing bio-based and environmentally friendly PSAs with high performance.
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