Polyesters of 2-Pyrone-4,6-Dicarboxylic Acid (PDC) Obtained from a Metabolic Intermediate of Lignin

• Published in: Polymer journal Vol. 40; no. 1; pp. 68 - 75
• Main Authors: Michinobu, Tsuyoshi, Hishida, Masakiyo, Sato, Masae, Katayama, Yoshihiro, Masai, Eiji, Nakamura, Masaya, Otsuka, Yuichiro, Ohara, Seiji, Shigehara, Kiyotaka
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.01.2008; Society of Polymer Science; Nature Publishing Group
• Subjects: Applied sciences; Biomaterials; Bioorganic Chemistry; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Polycondensation; Polymer Sciences; Preparation, kinetics, thermodynamics, mechanism and catalysts; regular-article; Surfaces and Interfaces; Thin Films; Hydrolysis; Mechanical Strength; Lignin; Polyester; Biomass; Biological properties; Metabolic intermediate; Biodegradability; Ester polymer; Mechanical properties; Composition effect; Lactone; Condensation polymerization; Pyranone derivatives; Experimental study; Thermal stability; Ester copolymer; Preparation; Copolycondensation; Ethylene terephthalate copolymer
• ISSN: 0032-3896; 1349-0540
• DOI: 10.1295/polymj.PJ2007158

2-Pyrone-4,6-dicarboxylic acid (PDC), a chemically stable metabolic intermediate of lignin, was for the first time utilized to prepare polyesters. Condensation polymerization at about 200 °C with 1,2-ethanediol, 1,3-propanediol or bis(2-hydroxyethyl) terephthalate was effectively promoted by the catalytic amount of Sb 2 O 3 . The corresponding polyesters, P(PDC2), P(PDC3) or P(PDCB) x (x: PDC unit content, and x ≤0.5), became insoluble when the number-average molecular weight exceeded about 4×10 3 . Due to the pseudo-aromatic nature of PDC ring, these polyesters were thermally stable up to 210 °C. From the measurements of strain-stress characteristics, Yong’s modulus of P(PDC2) or P(PDC3) was as high as 250 MPa and 2 times larger than that of amorphous PET. The accelerated hydrolysis of P(PDC2) or P(PDC3) in basic, acidic, and pure water at 60 °C gave 60–100% degradation in 1.5–3 weeks. The degradability could be controlled by changing the PDC content “x” in the case of P(PDCB) x , because the lactone ring cleavage as well as ester hydrolysis were considered to be the major events in the main-chain scission.