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The creation of high-performance polylactic acid (PLA) materials combining excellent mechanical robustness and flame-retardant performances are essential to meet demanding performances requirements for their practical applications in industry. Despite encouraging advances, current strategies by introducing toughening agents and flame retardants usually show compromised mechanical strength/ductility because of the irrational interphase reaction design of multi-component polymer blends. To date it remains challenging to robust and flame-retardant PLA via controlling interphase reactions. We, herein, report the rational design of mechanically robust and flame-retardant PLA by in situ manipulating interphase reactions between PLA, epoxidized soybean oil (ESO), a biobased and inexpensive toughening agent, and ammonia polyphosphate (APP), an effective eco-friendly flame retardant. We show that in addition to a high tensile strength of 42.0 MPa, as-designed PLA/ESO/APP ternary blend exhibits a high extensibility of 165% and a fracture toughness as high as 46 MJ/m3, which are respectively 21 and 14 folds of that of the bulk PLA. Meanwhile, a desired V-0 rating and a high limited oxygen index of 30.2% are achieved. Such outstanding performance portfolios are enabled by the rational manipulation of interphase reactions, leading to the in situ formation of favorable phase structures. This work offers an innovative methodology for facilely and massively creating high-performance multi-component polymer blends by tailoring interphase reactions, and contributes to expanding the extensive applications of PLA. Image 1 • Advanced PLA/ESO/APP ternary blends have been rationally designed via manipulating interphase reactions. • As-designed PLA/ESO/APP blend exhibits a large extensibility of 165% and a fracture toughness as high as 46 MJ/m3. • The PLA/ESO/APP ternary blend retains a high tensile strength of 42.0 MPa. • The PLA/ESO/APP blend can pass a V-0 rating in addition to showing a high LOI of 30.2%. [ABSTRACT FROM AUTHOR]

Acrylonitrile-butadiene-styrene (ABS), as one of the most widely used engineering plastics, suffers from the problem of serious flammability and low mechanical strength. To address such an intractable challenge, herein, we report the design of a graphene-based multifunctional additive (Sb-Mo/Br-rGO) via the bromination followed by precipitating antimony molybdenum. The surface functionalization enables Sb-Mo/Br-rGO to homogeneously disperse within the ABS matrix through facile melt-blending. The incorporation of 5 wt% Sb-Mo/Br-rGO leads to a 31% increase in tensile strength and 73% increase in elastic modulus relative to the ABS bulk. In addition to significant enhancement in thermal stability, the inclusion of 5 wt% Sb-Mo/Br-rGO significantly delays the time to ignition of ABS by 12 s, and noticeably reduces the peak heat release rate (PHRR) and total smoke production (TSP) by 45% and 54%, respectively. Such improved performance portfolio is primarily because the mechanical reinforcing and thermal barrier effect of graphene nanosheets, the flame retardant effect of bromine/antimony, and the smoke suppression action of antimony molybdenum. This work provides an innovative methodology for the design of multifunctional additives to create high-performance polymeric materials with high strength and low flammability, thus contributing to improving the quality of life. Image 1 • A novel multifunctional graphene-based flame retardant, Sb-Mo/Br-rGO, has been fabricated. • The addition of 5 wt% of SbMo-BrG increases tensile strength of ABS from 52.2 to 68.4 MPa. • The addition of Sb-Mo/Br-rGO significantly extends the time to ignition of ABS. • The addition of 5 wt% Sb-Mo/Br-rGO respectively reduces the PHRR and total smoke production by 45% and 54%. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional small molecule (HCPA) has been prepared. • The presence of HCPA endowed PVA with a nanostructure within the continuous matrix. • 5 wt% of HCPA endows PVA with a self-extinguishing behavior. • 5 wt% of HCPA increases tensile strength of PVA by 47% and toughness by 370%. • The PVA/HCPA composites exhibit a water-trigged healing efficiency over 90%. The combination of high fire retardancy, high strength, and great toughness as well as good healability is essential for successful real-world applications of polymeric materials in the fields of packaging, electronics & electrics, and optical devices. To date, there have been few successes in achieving such performance portfolios in polymers due to their different and even mutually exclusive governing mechanisms. Inspired by the nanoconfinement effect that governs the unique mechanical properties of spider silk, we, herein, rationally design a multifunctional small molecule, HCPA, that can serve as a fire retardant and hydrogen-bond crosslinker for poly(vinyl alcohol) (PVA). Benefiting from the dual-phase fire-retardancy effect and the dynamic cross-linking effect, the addition of 5.0 wt% of HCPA enables PVA to achieve a desired self-extinguishment in combination with a high tensile strength of 133 MPa and a toughness of 112 MJ/m3. In addition, the as-prepared polymer material exhibits a high healing efficiency of over 90% (based on strength) if triggered by water. This proof-of-concept opens numerous opportunities for the creation of self-extinguishing, strong, tough, and self-healing polymers for many high-end applications in the above-mentioned industries. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional heterostructure additive (CuP-MXene) has been prepared. • 5 wt% of CuP-MXene increases antibacterial efficiency of EP up to 99.99%. • 5 wt% of CuP-MXene endows EP with a self-extinguishing behavior. • The presence of CuP-MXene improves mechanical strength and impact toughness of EP. • The peak heat release rate and total smoke release are reduced by 64.4% and 40.5%. The ongoing Covid-19 pandemic has raised the need for urgent antibacterial requirements for many commercially important polymers, e.g., Epoxy resins (EPs). Meanwhile, intrinsic flammability and poor impact toughness are two big obstacles that greatly impede the practical applications of EPs. Hence, it has been imperative but highly challenging to create advanced EPs combining satisfactory antibacterial, fire-retardant and mechanically robust performances so far. Here, we report a reactive multifunctional heterostructure, copper-organophosphate-MXene (CuP-MXene) by rational design. Our results show that with 5.0 wt% of CuP-MXene, in addition to achieving a high antibacterial efficiency above 99.9%, the resultant EP nanocomposite exhibits satisfactory flame retardancy (UL-94 V-0 rating, peak heat release rate decreased by 64.4%) and improved mechanical properties (tensile strength, elastic modulus and impact strength increased by 31.7%, 38.9%, and 25.0%, respectively) relative to virgin EP, outperforming its previous counterparts. Such a desirable performance portfolio arises from multiple synergistic effects between CuP and MXene. This work provides a general strategy for the design of multifunctional nanoadditives and advanced functional polymers, and creates more opportunities for industrial applications of EP in the areas of coatings, medical devices and furniture. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional MXene-based hybrid (Zr-MXene) has been prepared. • 1 wt% of Zr-MXene increases ductility and toughness of TPU by 33% and 88%, respectively. • 1 wt% of Zr-MXene increases the tensile strength and fatigue resistance of TPU. • The addition of Zr-MXene significantly reduce the flammability of TPU. • The peak heat release rate and peak smoke production rate are respectively reduced by 63% and 56%. Thermoplastic polyurethane (TPU) features many important industrial applications, but intrinsic flammability extremely impedes its practical applications. Current fire-retardant strategies often lead to improved flame retardancy but reduced mechanical properties (strength, ductility, and toughness). Hence, to date it has been unsuccessful to design advanced TPU materials that are strong, stretchable, tough, fatigue-and fire-resistant to meet increasing performance portfolio requirements. Here, we report a hybridized fire retardant (Zr-MXene) by in situ facilely loading zirconium amino-tris-(methylenephosphonate) (Zr-AMP) onto the titanium carbide (MXene) surface. Our results show that with 1 wt% of Zr-MXene, the resultant TPU nanocomposites demonstrate a record break strain (2060%) and toughness (316 MJ/m3) to date, in addition to increased tensile strength by 43.4% and improved fatigue resistance relative to the TPU matrix, because of favorable interfacial hydrogen-bonding. Moreover, the resultant TPU material exhibit significantly reduced flammability as a result of the combined physical barrier, catalytical carbonization and diluting effects of Zr-MXene. This work provides a promising strategy for the creation of multifunctional MXene and its polymeric nanocomposites, which hold great promise for many industrial applications. [ABSTRACT FROM AUTHOR]