Renewable rosin fatty acid polyesters: the effect of backbone structure on thermal properties

Two novel polyesters were prepared from renewable natural molecular biomass castor oil–derived fatty acid and rosin. Highly efficient monomer syntheses including thiol-ene click chemistry and condensation po-lymerization techniques including transesterification and acyclic diene metathesis were carried out. Their thermal properties were compared based on flexible and rigid structural motifs on the polymer backbone. Although linear polymer backbone led to the formation semicrystalline polymers, polymers with fused-ring structure in the back-bone were amorphous. The presence of the rosin moiety in the backbone also resulted in higher glass transition temperature compared with the flexible linear counterpart.