Condensation Polyesters

Condensation polyesters are composed of monomers linked by ester bonds synthesized by a condensation reaction. The inherent reversibility of ester formation in the presence of water, and susceptibility by enzymatic attack, allows for polymer degradation under natural conditions. Therefore, biodegradable condensation polyesters are used in several applications in biomedical, agricultural, and packaging industries. Therein, the degradability directly contributes to the product value by functionality improvement or cost reduction. Still, with the increasing attention to waste management of plastics, research toward biodegradable condensation polyesters is ongoing. This chapter deals with the main classes of biodegradable condensation polyesters that include aliphatic, semi-aromatic, and thermoset polyesters. Within these classes, the most relevant polymers such as poly(butylene succinate) (PBS) and copolymers, poly(hydroxy acids), cyclic sugar-based polyesters, poly(butylene adipate- co -terephthalates) (PBAT), poly(butylene succinate- co -furanoate) (PBSF), poly(diol citrates), poly(glycerol dicarboxylates), and poly(propylene fumarates) (PPFs) are outlined for their synthesis, physical and thermal properties, and degradability. Furthermore, the synthesis, biodegradation, applications, and recycling of condensation polyesters are also explained.