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The future of green electronics possessing great strength and toughness proves to be a promising area of research in this technologically advanced society. This work develops the first fully bendable and malleable toughened polylactic acid (PLA) green composite by incorporating a multifunctional polyhydroxybutyrate rubber copolymer filler that acts as an effective nucleating agent to accelerate PLA crystallization and performs as a dynamic plasticizer to generate massive polymer chain movement. The resultant biocomposite exhibits a 24‐fold and 15‐fold increment in both elongation and toughness, respectively, while retaining its elastic modulus at >3 GPa. Mechanism studies show the toughening effect is due to an amalgamation of massive shear yielding, crazing, and nanocavitation in the highly dense PLA matrix. Uniquely distinguished from the typical flexible polymer that stretches and recovers, this biocomposite is the first report of PLA that can be “bend, twist, turn, and fold” at room temperature and exhibit excellent mechanical robustness even after a 180° bend, attributes to the highly interconnected polymer network of innumerable nanocavitation complemented with an extensively unified fibrillar bridge. This unique trait certainly opens up a new horizon to future sustainable green electronics development.

The sustainable biopolymer, poly(lactide) (PLA), has been intensely researched over the past decades because of its excellent biodegradability, renewability, and sustainability. The boundless potential of this sustainable biopolymer could resolve the adverse negative impact caused by the petroleum-based polymers. However, the inherent drawback of PLA such as brittleness, low heat distortion temperature, and slow recrystallization rate narrowed the broad applications in biomedical, automotive, and structural fields. In this study, we successfully synthesized a PHB-based filler (PHB-di-rub) displaying synergetic functions of (1) effective nucleation and (2) extreme toughening of the PLA matrix at only 5% (1.5 wt % PHB content). Remarkably, the storage modulus improves by 15%; tensile elongation extends by 57-fold (300% strain) and toughness by 38-fold while maintaining its original strength and stiffness. Likewise, 10% of PHB-di-rub (3 wt % PHB content) has an even higher improvement with a storage modulus improvement by 32%, elongation by 128-fold (680% strain), and toughness by 84-fold, with a marginal change in strength and stiffness. NMR results confirmed the structure of PHB-di-rub, where PHB acts as the rigid core and the poly(lactide-cocaprolactone) (DLA-co-CL) random copolymer confers the flexibility. DSC, WAXD, and POM display the excellent nucleating ability of PHB-di-rub. SEM shows the morphology of elongated fibrils structure with strong matrix−filler interaction and homogeneous filler dispersion. SAXS, WAXS, and WAXD elucidate the extreme toughening mechanism to be a combination of rubber-induced crazing effect and highly orientated PLA matrix with PHB-di-rub. The Herman's orientation function further quantifies the extreme elongation (680%) owing to the perfect alignment. This highly biodegradable biocomposite with high strength and toughness shows potential in replacing the current petroleum-based polymers, which open up to broader prospects in the biomedical, automotive, and structural application.

Poly­(dimethylsiloxane) (PDMS) as one of the electron-drawing materials has been widely used in triboelectric nanogenerators (TENG), which is expected to generate electron through friction and required to endure dynamic loads. However, the nature of the siloxane bond and the low interchain interaction between the methyl side groups result in low fracture energy in PDMS elastomers. Here, a strategy that combined the advantages of the dynamic of hierarchical hydrogen bonding and phase-separation-like structure was adopted to improve the toughness of PDMS elastomers. By varying both stronger and weaker hydrogen bonding within the PDMS network, a series of super tough (up to 24,000 J/m2), notch-insensitive, transparent, and autonomous self-healable elastomers were achieved. In addition, a hydrophilic polymeric material (PDMAS-U10) was synthesized as the conductive layer. A transparent TENG was fabricated by sandwiching the PDMAS-U10 between two pieces of the PDMS elastomer. Despite its hydrophilic nature, PDMAS-U10 exhibit strong adhesion interaction with hydrophobic PDMS elastomers. As such, a tough (16,500 J/m2), self-healable (efficiency ∼97%), and transparent triboelectric nanogenerator was constructed. A self-powered system employing the TENG is also demonstrated in this work.

A novel route to lignin epoxy composites is developed through covalent incorporation of depolymerized lignin epoxide into amine‐cured epoxy matrix. The partially depolymerized lignin is first epoxidized with epichlorohydrin and the resultant depolymerized lignin epoxide shows decreased solubility in common organic solvents. When dispersed in epoxy matrix and cured, the depolymerized lignin epoxide is integrated into epoxy networks in the form of submicron aggregates. The resulting lignin epoxy composites show improved mechanical properties compared with neat epoxy. At a loading content of 1.0 wt% of degraded lignin epoxide, the Young's modulus and the critical stress intensity factor (KIC) of the composite increase by 10% and 25%, respectively, in comparison with those of neat epoxy, while the glass transition temperature is little changed. This method presents a promising way to convert wasteful lignin to an alternative epoxy monomer and effective additive in epoxy composites.

The runaway production and consumption of oilbased plastics are key drivers of global warming and the increased carbon footprint. Besides, most of this plastic debris ends up in the oceans and constitutes about 80% of all marine debris. This pollution problem calls for a seismic shift to eco-friendly plastics and marine biodegradable ones. Unlike other biobased polymers, polyhydroxyalkanoates (PHAs) take pride in their degradation in soil and marine environments. This intriguing marine biodegradation property of PHAs sets it apart as the best choice to curb microplastics, particularly in marine ecosystems. PHAs have also grown in popularity due to other quintessential properties such as biocompatibility, structural variety, and similarity to conventional plastics in terms of physical properties. PHAs are being widely researched for various applications, including packaging, medical, energy, and agriculture. This perspective comprehensively focuses on the state-of-art production and applications of PHA plastics as well as the practical recycling strategies for postconsumer PHAs. The innovative "next generation industrial biotechnology" (NGIB) is well covered in this perspective. Moreover, the nexus between end-of-life strategies and life cycle assessment (LCA) of PHAs waste is elucidated to understand its impact on the environment thoroughly.

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