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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]

The friction and thermal conductivity are two vital factors affecting braking components in manned aircraft. It is imperative to find a rational design basis for high-performance lightweight polymeric materials with excellent toughness, coefficient of friction, and thermal conductivity. In light of the outstanding mechanical strength, stiffness, and good dimensional stability of polyamide 6 (PA6), herein, we have demonstrated the fabrication of high-performance PA6 composites by adding one-dimensional SiC whiskers (SCWS) as both a reinforcement agent and anti-abrasion agent. The results show that addition of 2 wt% SiC whiskers (SCWS) increases the tensile strength of PA6 by 37.6% (reaching 58.2 MPa). Meanwhile, the elongation at break is over five times (around 280%) of that of the PA6 matrix, which means that the fracture toughness is increased around seven-fold. Moreover, the addition of 30 wt% SCWS reduces the coefficient of friction from 0.31 for the PA6 to 0.15, indicating improved anti-abrasion performance. Such significant improvements in both mechanical and anti-wear properties are primarily due to the high stiffness of SCWS and the strong interfacial interactions with the PA6 matrix. This work provides a facile approach to the design of mechanically robust, wear-resistant polymer composites which hold significant promise for producing advanced gears and bearing parts in aerospace and automobile applications. • High-performance PA6 composites by adding various loading levels of SiC whiskers (SCWS) were prepared. • The addition of 2wt% SCWS increases the tensile strength of PA6 by 37.6%. • Adding 2wt% of SCWS increases the elongation at break of PA6 over 5 times and the fracture toughness by around 7 times. • The addition of 30 wt% SCWS reduces the friction coefficient from 0.31 for the PA6 to 0.15. [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]