Study on the Synthesis and Properties of Biodegradable Poly(butylene diglycolate) Polyester

Abstract

With increasing environmental requirements, biodegradable polymers have received widespread attention. Herein, we synthesized a series of poly(butylene diglycolate)s (PBDs), which was a novel biodegradable homopolyester, with numberaverage molecular weight (M n ) values between 13 and 97 K g• mol −1 . The effects of M n on the thermal and tensile properties of PBDs were comprehensively investigated. The glass transition temperature (T g ), melting temperature (T m ), and temperature of 5% weight loss (T d,5% ) of PBDs were found to be approximately −26.4, 64.0, and 336 °C, respectively. PBD with 31 K g•mol −1 exhibits a brittle fracture feature, while obvious yielding behavior occurs when the M n of PBD is higher than 45 K g•mol −1 . Besides, PBD achieves stable mechanical properties when M n reaches 51 K g•mol −1 , with the elastic modulus, tensile strength, and elongation at break of 285, 27.1 MPa, and 290%, respectively, superior to those of linear low-density polyethylene (LLDPE). Furthermore, the crystal structures of PBD were recorded by WAXD and POM. The spherulites were observed after isothermal crystallization of PBD in a wide temperature range, and the maximum nucleation density was obtained after annealing at 20 °C. Significant hydrolysis of PBD in both buffer solution and artificial seawater was confirmed by monitoring the changes in residual weight, intrinsic viscosity, surface morphology, crystallinity, and chemical composition. Finally, PBD exhibits considerable biodegradability under composting and freshwater environments, with the residual weight reducing to 49.2 and 94.7% after 35 days, respectively. Due to the balanced mechanical and barrier properties and biodegradability, PBD has potential application prospects in packaging materials.

Biodegradable and Structure-Tunable Poly(lactic acid) Foam Prepared by Temperature-Induced CO2 Foaming

“…Owing to their low cost and fascinating chemical and physical properties, plastics have been extensively applied in many fields, such as packaging, transportation, and construction, which brings tremendous convenience to people’s lives. , However, most of them are nondegradable and often discarded after use, thus leading to severe environmental issues. − Therefore, the application of biodegradable polymers, specially made from renewable resources, has become an urgency for environmental sustainability. Poly­(lactic acid) (PLA) derived from biobased sources, such as crops and waste sugars, , is one of the most produced biodegradable and biocompatible polymers.…”