Overcoming strength-ductility and functional period-degradability tradeoffs: Multifunctional biodegradable polyesters with ionic cluster skeleton and PDMS skin

Abstract

To overcome the strength-ductility and functional period-degradability tradeoffs of biodegradable polyesters, we proposed a nanophase structure design strategy to construct a soft-hard dual phase in poly(butylene succinate) (PBS) copolymers by simultaneously introducing polydimethylsiloxane (PDMS) and isophthalate-5-sulfonate (SIPM) on PBS macromolecular chains to improve the stiffness, toughness, and multifunctionality. The high-resolution transmission electron microscope (HR-TEM) and energy dispersive X-Ray spectroscopy (EDX) tests indicated that PBS copolymers possessed continuous “ionic cluster skeleton” and “PDMS skin”. The hybrid liquid state theory and self-consistent field approach for copolymers further demonstrated the mechanism of microphase separation for PDMS blocks and SIPM segments. The copolymers showed excellent yield strength of 52 MPa, great impact strength of 171 J/m, large extensibility of 491 %, and long functional period in the acidic environment. The novel stereo nanostructure endowed the materials with advanced multifunctions that can be applied in various applications, such as the biomedical field and flexible electronic devices. Compared with PBS, copolymers possessed excellent in vitro attachment and proliferation of MC3T3-E1 cells. Furthermore, the synergistic effect of the ionic skeleton and PDMS skin improved the ionic conductivity of the materials. The copolymer film was innovatively employed as anion-exchanging separators of supercapacitors with acid-organized electrolytes. It has been testified that this newly designed strategy of a novel stereo nanophase structure was efficient in endowing the biodegradable polyesters with excellent combined properties and multifunctions.