Biodegradable Copolyesters with Unexpected Highly Blocky Microstructures and Enhanced Thermal Properties

To synthesize novel biodegradable polyesters with high heat resistance and good crystallization capability, we designed a series of aliphatic-aromatic copolyesters, i.e., poly-(isoidide-2,5-dimethylene adipate-co-terephthalate)s (PIATs)based on isoidide-2,5-dimethanol (IIDML), a rigid carbohydrate-based building block. TheMnvalues and intrinsic viscosities ofPIAT copolyesters containing up to 40 mol % aromatic moietiesare in the range of 6 000-19 000 gmiddotmol-1and 0.5-0.87 dLmiddotg-1,respectively. Interestingly, the products were obtained as blockycopolymers after the one-pot melt polycondensation processbecause of the thermodynamic equilibrium of IIDML moietiesdriven by the insufficient thermal stability of the IIDML moieties. In addition, all the copolyesters are semicrystalline withcrystallinity from 28% to 55% and tunableTmvalues ranging from 88 degrees C to a remarkable 189 degrees C. They exhibit better(bio)degradability than the same type of polyesters. This work shows that this green monomer plays a key role in balancing thermalproperties (especiallyTg) and (bio)degradability, and these polyesters potentially broaden the application toward, for example, fibers

Automated summary

In this study, a novel biodegradable polyester with high heat resistance and good crystallization capability was synthesized. The use of a green monomer resulted in blocky copolymers with tunable thermal properties. These polyesters have potential applications in various fields, such as fibers.