Ultrafast-degradable and super-elastic PBAT/polybutylene succinate foam with stable cellular structure and enhanced thermal insulation

PBAT is considered a leading eco-friendly polymer known for its exceptional biodegradability and mechanical properties. However, the production of high-performance PBAT foam remains challenging owing to poor foaming ability and intrinsic shrinkage. Herein, this study presents a flexible approach to prepare super-elastic and ultrafast-degradable PBAT/polybutylene succinate (PBS) foams achieved by microcellular foaming with CO2 & N2 as co-blowing agents. Firstly, the SEM, FTIR, as well as XPS spectra, confirmed a uniform and miscible distribution of PBS. Further, the crystallization kinetics and rheological analysis demonstrated that PBS effectively promoted crystallization and molecular chain entanglement. Thus, the PBAT/PBS foam exhibited significantly refined cellular structure, higher expansion ratio of 20.3, and restricted shrinkage of less than 4 %. More importantly, compared with neat PBAT foam, the compression strength of PBAT/PBS foam was dramatically enhanced by 47.7 %, and the energy loss coefficient was pronouncedly reduced by 58.8 % under the expansion ratio of 15.0. Meanwhile, the PBAT/PBS foam showed a thermal conductivity as low as 35.9 mW/m·K, enhanced hydrophobicity, and an exceptionally rapid degradation ratio. Considering the eco-friendly and flexible characteristics of this process, anti-shrinkage and ultrafast-degradable PBAT/PBS foams with improved mechanical and thermal insulation performance present promising prospects to replace the nondegradable polymer foams.