Tough and circular glass fiber composites a tailored dynamic boronic ester interface.

Glass fiber reinforced polymer (GFRP) composites are valued for their strength and cost-effectiveness. However, traditional GFRPs often face challenges for end-of-life recycling due to their non-depolymerizable thermoset matrices, and long-term performance due to inadequate interfacial adhesion, which can lead to fiber-matrix delamination. Here, we have designed dynamic fiber-matrix interfaces to allow tough and closed-loop recyclable GFRPs by utilizing a vitrimer, derived from upcycled polystyrene--poly(ethylene--butylene)--polystyrene (SEBS) with boronic ester (S-Bpin) and amine-based diol crosslinker.

Enhancing Composite Toughness Through Hierarchical Interphase Formation.

High strength and ductility are highly desired in fiber-reinforced composites, yet achieving both simultaneously remains elusive. A hierarchical architecture is developed utilizing high aspect ratio chemically transformable thermoplastic nanofibers that form covalent bonding with the matrix to toughen the fiber-matrix interphase. The nanoscale fibers are electrospun on the micrometer-scale reinforcing carbon fiber, creating a physically intertwined, randomly oriented scaffold.

Fractionation of Lignin for Selective Shape Memory Effects at Elevated Temperatures.

We report a facile approach to control the shape memory effects and thermomechanical characteristics of a lignin-based multiphase polymer. Solvent fractionation of a syringylpropane-rich technical organosolv lignin resulted in selective lignin structures having excellent thermal stability coupled with high stiffness and melt-flow resistance. The fractionated lignins were reacted with rubber in melt-phase to form partially networked elastomer enabling selective programmability of the material shape either at 70 °C, a temperature that is high enough for rubbery matrix materials, or at an extremely high temperature, 150 °C.

An Ionomeric Renewable Thermoplastic from Lignin-Reinforced Rubber.

An ionomeric, leathery thermoplastic with high mechanical strength is prepared by a new thermal processing method from a soft, melt-processable rubber. Compositions made by incorporation of equal-mass lignin, a renewable oligomeric feedstock, in an acrylonitrile-butadiene rubber often yield weak rubbers with large lignin domains (1-2 µm). The addition of zinc chloride (ZnCl ) in such a composition based on sinapyl alcohol-rich lignin during a solvent-free synthesis induces a strong interfacial crosslinking between lignin and rubber phases.

Data of thermally active lignin-linkages and shape memory of lignin-rubber composites.

This data article presents the utilization of thermally dynamic covalent bonds of lignin linkages such as -O-4', Cα-O of -5' phenylcoumaran, and - resinol to modify the thermomechanical properties of high loading lignin-nitrile rubber composites. These thermally active lignin linkages can be triggered at 180 °C to generate free-radicals for crosslinking reactions. The evolution of crosslinking density was measured in-situ using dynamic mechanical analysis and rheological characterization.

A path for lignin valorization via additive manufacturing of high-performance sustainable composites with enhanced 3D printability.

We report the manufacture of printable, sustainable polymer systems to address global challenges associated with high-volume utilization of lignin, an industrial waste from biomass feedstock. By analyzing a common three-dimensional printing process-fused-deposition modeling-and correlating the printing-process features to properties of materials such as acrylonitrile-butadiene-styrene (ABS) and nylon, we devised a first-of-its-kind, high-performance class of printable renewable composites containing 40 to 60 weight % (wt %) lignin. An ABS analog made by integrating lignin into nitrile-butadiene rubber needs the presence of a styrenic polymer to avoid filament buckling during printing.

Roll-to-Roll Processing of Silicon Carbide Nanoparticle-Deposited Carbon Fiber for Multifunctional Composites.

This work provides a proof of principle that a high volume, continuous throughput fiber coating process can be used to integrate semiconducting nanoparticles on carbon fiber surfaces to create multifunctional composites. By embedding silicon carbide nanoparticles in the fiber sizing, subsequent composite fabrication methods are used to create unidirectional fiber-reinforced composites with enhanced structural health monitoring (SHM) sensitivity and increased interlaminar strength. Additional investigations into the mechanical damping behavior of these functional composites reveal a significantly increased loss factor at the glass-transition temperature ranging from a 65 to 257% increase.

Mechanical, thermal, morphological, and rheological characteristics of high performance 3D-printing lignin-based composites for additive manufacturing applications.

The article presents different mechanical, thermal and rheological data corresponding to the morphological formation within various renewable lignin-based composites containing acrylonitrile butadiene styrene (ABS), acrylonitrile butadiene rubber (NBR41, 41 mol% nitrile content), and carbon fibers (CFs). The data of 3D-printing properties and morphology of 3D-printed layers of selected lignin-based composites are revealed. This data is related to our recent research article entitled "A general method to improve 3D-printability and inter-layer adhesion in lignin-based composites" (Nguyen et al.

Barium Titanate Film Interfaces for Hybrid Composite Energy Harvesters.

Energy harvesting utilizing piezoelectric materials has become an attractive approach for converting mechanical energy into electrical power for low-power electronics. Structural composites are ideally suited for energy scavenging due to the large amount of mechanical energy they are subjected to. Here, a multifunctional composite with embedded sensing and energy harvesting is developed by integrating an active interface into carbon fiber reinforced polymer composites.

Conformal BaTiO3 Films with High Piezoelectric Coupling through an Optimized Hydrothermal Synthesis.

Two-dimensional (2D) ferroelectric films have vast applications due to their dielectric, ferroelectric, and piezoelectric properties that meet the requirements of sensors, nonvolatile ferroelectric random access memory (NVFeRAM) devices, and micro-electromechanical systems (MEMS). However, the small surface area of these 2D ferroelectric films has limited their ability to achieve higher memory storage density in NVFeRAM devices and more sensitive sensors and transducer. Thus, conformally deposited ferroelectric films have been actively studied for these applications in order to create three-dimensional (3D) structures, which lead to a larger surface area.

Lead-free 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 nanowires for energy harvesting.

Lead-free piezoelectric nanowires (NWs) show strong potential in sensing and energy harvesting applications due to their flexibility and ability to convert mechanical energy to electric energy. Currently, most lead-free piezoelectric NWs are produced through low yield synthesis methods and result in low electromechanical coupling, which limit their efficiency as energy harvesters. In order to alleviate these issues, a scalable method is developed to synthesize perovskite type 0.

Growth of highly textured PbTiO3 films on conductive substrate under hydrothermal conditions.

Perovskite structure (ABO(3)) thin films have wide applications in electronic devices due to their unique properties, including high dielectric permittivity, ferroelectricity and piezoelectric coupling. Here, we report an approach to grow highly textured thick lead titanate (PbTiO(3)) filmson conductive substrates by a two-step hydrothermal reaction. Initially, vertically aligned TiO(2) nanowire arrays are grown on fluorine-doped tin oxide (FTO) coated glass, which act as template crystals for conversion to the perovskite structure.