Synthesis of well-defined hyperbranched polymers bio-based on multifunctional phenolic acids and their structure-thermal property relationships

A number of multifunctional ABx-type monomers exist in plant metabolites, and studies on the formation of hyperbranching polymers from ABx-type monomers are very significant in the development of bio-related polymeric materials. We established a method for the preparation of well-defined structures in bio-based, hyperbranched (HB) polyarylates by the copolycondensation of caffeic acid (DHCA) as an AB2-monomer and p-coumaric acid (4HCA) as an AB-monomer, using the highly efficient catalyst Na2HPO4 to regulate the polymerization speed. 1H NMR analysis revealed the time course of the formation of the hyperbranching structures. which strongly affected the glass transition and degradation temperatures, as well as the molecular weight and composition.