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Advanced hybrid biocomposites are engineered from nylon 6, waste wood biosourced carbon (biocarbon) with a low content of synthetic fiber for lightweight auto‐parts uses. The novel engineering process through direct injection molding of only 2 wt% synthetic fibers in the form of masterbatch with 20 wt% biocarbon, results outstanding performance of the resulting nylon biocomposites. Such uniquely developed biocomposites show tensile strength of 105 MPa and tensile modulus of 5.14 GPa with a remarkable heat deflection temperature (HDT) of 206 °C. The direct injection molding of synthetic fiber retains the length ≈3 times higher as compared to traditional extrusion and injection molding; resulting greater degree of entanglement and composite reinforcement effectiveness in the hybrid biocomposites. Highly dimensionally stable nylon 6 biocomposites with a very low coefficient of linear thermal expansion results through reinforcing ability of the sustainable biocarbon and small amount of synthetic fiber. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mishandling of plastic and biomass waste poses significant global concerns, resulting in environmental and economic impacts. • Integrating 3D printing with waste upcycling offers environmental benefits and supports transition to circular economy. • The article examines the properties of recycled plastic 3D-printed parts, demonstrating comparable performance to virgin materials. • Explores the potential of incorporating waste biomass-derived fillers to further enhance mechanical properties. • Highlights the importance of optimizing printing parameters for improved strength, ductility, crystallinity, and dimensional accuracy. Mishandling of waste plastics and biomasses is a major global concern. Every year, around 380 million tonnes of plastic are produced, with only 9% being recycled, leading to widespread pollution. Similarly, waste biomass generation from agricultural and forestry sectors accounts for 140 billion metric tonnes, in addition to 2.01 billion tonnes from municipal solid waste. This review paper addresses the gap regarding the integration of 3D printing, upcycling of recycled plastics, and the utilization of waste biomass in sustainable composites. 3D printed parts from recycled plastic have shown comparable mechanical properties compared to virgin materials, which have been further improved by the addition of waste biomass-derived fillers. The paper acknowledges that different printing parameters have substantial influence on the strength, ductility, crystallinity, and dimensional accuracy of printed parts. Therefore, optimizing these parameters becomes crucial for achieving improved mechanical performance. Moreover, incorporating reinforcing agents, stabilizers, chain extenders, compatibilizers, and surface modifiers in plastic recycling and 3D printing presents an excellent opportunity to enhance mechanical properties, thermal stability, adhesion, and dimensional stability. Additionally, the review identifies research gaps and proposes the integration of machine learning and artificial intelligence for enhanced process control and material development, further expanding the possibilities in this field. [ABSTRACT FROM AUTHOR]

Pine wood derived biocarbon (BioC) is investigated as a renewable alternative to carbon black (CB) for plastics and composites applications. Three different polymers with different polarity were used to prepare the composites: polypropylene (PP), polylactic acid (PLA), and polyamide 6 (PA6). Comparatively, CB had a nodule size of ~300 nm and surface area of 8 m2/g, whereas BioC showed an average particle size of ~950 nm and surface area of ~260 m2/g, respectively. CB, in the composites, was found in large aggregations in the flow direction (FD), while BioC particles showed a better dispersion. Aggregation of CB affected mostly the mechanical strength of the composites. Furthermore, it was found that the overall performance of composites was influenced more by the polarity of the phases, rather than the particle size or the surface area of the fillers. Even when the polarity of the particles had an expected trend (PA6 > PLA > PP with BioC > CB), the work of cohesion obtained for the composites was PA6‐BioC > PP‐BioC > PLA‐BioC, showing, in particular, that the chain‐to‐chain intermolecular forces in neat PLA are stronger as compared to those developed by the particle‐matrix interactions. [ABSTRACT FROM AUTHOR]

A full factorial design with four factors (the ratio of polyphthalamide (PPA) and polyamide 4,10 (PA410) in the polymer matrix, content percent of biocarbon (BioC), the temperature at which it was pyrolyzed and the presence of a chain extender (CE)), each factor with two levels (high and low), was carried out to optimize the mechanical properties of the resulting composites. After applying a linear model, changes in tensile strength, elongation at break and impact energy were not statistically significant within the considered material space, while the ones in the flexural modulus, the tensile modulus, density and heat deflection temperature (HDT) were. The two most influential factors were the content of BioC and its pyrolysis temperature, followed by the content of PPA. The affinity of PPA with a high-temperature biocarbon and the affinity of PA410 with a lower-temperature biocarbon, appear to explain the mechanical properties of the resulting composites. The study also revealed that the addition of CE hindered the mechanical properties. By maximizing the flexural modulus, tensile modulus and HDT, while minimizing the density, the optimal composite predicted is an 80 [PPA:PA410 (25:75)] wt% polymer composite, with 20 wt% of a BioC, pyrolyzed at a calculated 823 °C. [ABSTRACT FROM AUTHOR]

Miscanthus biocarbon (MB), a renewable resource-based, carbon-rich material, was melt-processed with poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) to produce sustainable biocomposites. The addition of the biocarbon improved the Young's modulus of PHBV from 3.6 to 5.2 GPa at 30 wt % filler loading. An increase in flexural modulus, up to 48%, was also observed. On the other hand, the strength, elongation-at-break and impact strength decreased. Morphological study of the impact-fractured surfaces showed weak interaction at the interface and the existence of voids and agglomerates, especially with high filler contents. The thermal stability of the PHBV/MB composites was slightly reduced compared with the neat PHBV. The biocarbon particles were not found to have a nucleating effect on the polymer. The degradation of PHBV and the formation of unstable imperfect crystals were revealed by differential scanning calorimetry (DSC) analysis. Higher filler contents resulted in reduced crystallinity, indicating more pronounced effect on polymer chain mobility restriction. With the addition of 30 wt % biocarbon, the heat deflection temperature (HDT) became 13 degrees higher and the coefficient of linear thermal expansion (CLTE) decreased from 100.6 to 75.6 μm/(m·°C), desired improvement for practical applications. [ABSTRACT FROM AUTHOR]

Degradation is an unavoidable part of a material's life making it important to both monitor and control the aging behavior of plastics. This study compares thermooxidative degraded composites of a novel bio‐based and sustainable filler, Biocarbon (MBc), against that of traditional and commercially available fillers (glass fiber and talc) used in the automotive industry. The influence of thermooxidative degradation on the composites was studied under accelerated heat aging for 1000 h at 140°C. The mechanical properties of the composites were evaluated using notched Izod impact as well as both tensile and flexural tests. Morphological structure of the composites was investigated using a scanning electron microscopy. Dynamic mechanical analysis and differential scanning calorimetry were used to evaluate the physical transitions both before and after aging. The glass‐filled composites displayed the best performance; while, both the talc and biocarbon composites possessed similar strength and ductility performances. Advantageously, the biocarbon composites experienced an 11% reduction in density as compared to talc‐filled composites with similar weight content. After aging, all composites exhibited reduced tensile and flexural strengths ranging from 5 to 67% partly due to chain scission. Whereas, the modulus of all composites increased with a range of 1–24% due to an annealing effect. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48618. [ABSTRACT FROM AUTHOR]

The structure-property relationships of toughened polypropylene/biocarbon biocomposites prepared via melt extrusion are investigated with a focus on the effects of biocarbon particle size, functional polymer type and concentration. A full factorial design was utilized to study each factor's main effect and how their interactions with other factors affect the final mechanical properties of the biocomposites. The statistical analysis confirmed the synergistic interactions between the biocarbon and the functional polymer which improves the impact toughness of the composites by 120% while maintaining or improving the stiffness of the composite. Among the investigated factors, the type of functional polymers had the greatest impact on the properties by affecting the morphology of phases. Based on these analyses, the biocarbon with particle size range of 106–125 μm together with 5.0 wt% of maleic anhydride grafted polypropylene was selected as the optimum composite formulation providing the best stiffness-toughness balance among the tested samples. [ABSTRACT FROM AUTHOR]

Using biocarbon as a biobased filler in polymers is gaining increased attention because of its carbon neutrality and low cost. However, systematic studies investigating the effect of pyrolysis temperature on the surface characteristics and properties of biocarbon and how these biocarbon affect the composite properties are lacking. In this study, biocarbons from pyrolyzed miscanthus grass at two different conditions were characterized for their physical and chemical properties for biocomposites uses. To evaluate the effect of these biocarbons in polyolefin based biocomposites, two loading levels of 10 and 20 wt % of each biocarbon sieved to a particle size range of 20–75 μm were melt blended with a toughened polypropylene/poly (octene-ethylene) copolymer (POE) (70/30 wt %) blend. The results validated that higher pyrolysis temperature eliminated the surface functional groups and increased the specific surface area which promoted better compatibility between the biocarbon and polyolefin matrix. Also, the high temperature pyrolyzed biocarbon (HTBioC) produced significantly better stiffness-toughness balance in the composite compared to low temperature pyrolyzed biocarbon (LTBioC). Morphology of the composites and biocarbon were analyzed by scanning electron microscopy (SEM), nano-mechanical mapping through atomic force microscopy (AFM), surface area and pore size distribution measurements. The results confirmed encapsulation of both types of biocarbons by the POE phase. Filler-polymer interactions were compared using dynamic strain and frequency sweep rheometry and results were suggesting that HTBioC had stronger interactions with the matrix. While HTBioC caused nucleating effect on the matrix no changes were observed in crystallization behavior of LTBioC based composites. [ABSTRACT FROM AUTHOR]

Nylon/biocarbon biocomposites show great potential for semi-structural auto-part applications due to their enhanced mechanical and physical properties. However, the long term durability of these biocomposites has never been studied before. The durability of the biocomposite was compared to that of talc reinforced nylon composite at 20 wt. % for both composites. They were subjected to accelerated and aggressive conditioning by complete immersion in water at 85 °C for prolonged periods of time up to 28 days. The water uptake of the nylon/biocarbon biocomposite was reduced in comparison to that of the nylon suggesting that biocarbon particles act as a barrier while also concentrating the absorbed moisture within its pores and around the interface with nylon. Thermal properties revealed little changes in the crystallinity of the nylon/biocarbon composites. However, the glass transition temperature was observed to decrease significantly after conditioning due to the presence of bound water molecules within the amorphous phase of nylon. The impact strength remained mostly unchanged even after conditioning, suggesting interaction between biocarbon and nylon to restrict the chain mobility and thereby annulling the effect of moisture on the nylon. The morphology of the impact fractured surface of the conditioned sample revealed two distinct phases. One was significantly affected by moisture, revealed swelling and debonding of biocarbon particles from the nylon matrix while the other remained unchanged when compared to that of the unconditioned sample. [ABSTRACT FROM AUTHOR]

Highly order-structured carbon-based materials such as graphite, graphene, and carbon nanotubes hold promise in delivering the next generation of carbon-based advanced composite materials due to their superior performance in many applications. Recently, partially graphitic biosourced carbon (BioC) has shown to be a new, sustainable, inexpensive and practical alternative carbonaceous functional filler for polymer and biocomposite development (i.e. thermoplastic, thermoset, elastomer and foam). The thermochemical conversion of different types of biomass in a limited oxygen environment (pyrolysis) can be controlled and optimized to produce engineered BioCs with tunable surface area, morphology, polarity, porosity, intrinsic modulus and carbon content, which are being explored in different applications. Renewable BioCs exhibit variable surface chemistry that can be further modified to achieve better compatibility with polymers. BioC can be used as a reinforcing agent and as a multi-functional filler (e.g. electrical conductivity, antimicrobial, fire retardant, etc.) for polymer composite uses, which opens a new generation of biobased composite materials in the commercial market. This article provides an in-depth review of the current state-of-the-art fabrication, characterization, and performance of the BioC-based biocomposites. Further, the effect of the different synthesized BioCs on the polymers' behavior and performance are reviewed in-depth. Finally, the challenges and future perspectives for these BioC-based biocomposites are discussed. • Sustainable biosourced carbons (BioC) for composite applications were reviewed. • Tuning the pyrolysis conditions produced BioC with varying key functionalities. • Highly graphitic engineered BioC provides substantial boost in composite modulus. • BioC exhibited great potential to replace mineral fillers and carbon blacks in biocomposites uses. [ABSTRACT FROM AUTHOR]

Oxidative acid treatments of biochar produced from Miscanthus were performed in this study using nitric acid, sulfuric acid, and a mixture of both. The structural and morphological changes of the acid-treated biochar were investigated using Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Raman spectroscopy, organic elemental analysis and energy-dispersive X-ray spectroscopy (EDS). Improved surface functionality of the treated biochars was observed in their respective FT-IR spectra through the presence of nitro and carboxylic acid functional groups. SEM–EDS and elemental analysis revealed a large increase in the oxygen to carbon ratio in the biochar, which was evidence of chemical oxidation from the acid treatment. Further, TGA study showed the reduced thermal stability of acid-treated biochar over 200 °C due to the increased oxygen content. Acid treatments also influenced the graphitic structure of the biochar, as observed in the Raman spectra. The results suggest that biochar can be successfully functionalized for composite applications and provide a sustainable alternative to petroleum-based carbon additives. [ABSTRACT FROM AUTHOR]

[Display omitted] • Lycoperdon Sp. (puffball) spores were effectively converted into hierarchical biocarbon. • Puffball spores showed excellent structural (size and shape) retention during carbonization. • Puffball biocarbon found in the size range of 2.6–3 µm with hierarchical morphology. • Pristine puffball biocarbon showed the specific capacitance of 33 F/g at 1 A/g in symmetrical supercapacitors. Puffball (Lycoperdon Sp.) spores were effectively explored as a new class of renewable feedstock for the synthesis of hierarchical nanostructured biocarbon. The systematic characterization of the puffball spores and their derived biocarbon material indicates the effective retention of their hierarchical structure during the carbonization with minimum size shrinkage. The derived biocarbon found to have a uniform size ranging from 2.6 to 3 µm with nanostructured hierarchical morphology and the specific surface area of 51.5 m2/g. The preliminary investigation on their application potential is explored for the energy storage application. The fabricated symmetric supercapacitor using the puffball spores derived biocarbon electrodes showed the specific capacitance of 33 F/g at 1 A/g and the capacitance retention of 96.2% after 1000 cycles. [ABSTRACT FROM AUTHOR]

Biomaterials have gained attention in automotive industries for their renewability and environmental benefits. This study evaluates the life cycle environmental impacts and benefits of the automotive component produced from biocomposite (biomaterials, i.e., polypropylene (PP) reinforced with biocarbon and Miscanthus fiber) relative to the component produced from conventional composite (PP reinforced with talc and colorant; hereafter referred to composite) using the life cycle assessment (LCA) methodology. To accomplish this study, the LCA software (SimaPro 8.0.4.26) and the Ecoinvent database (v3.1) are used. Miscanthus , an energy crop grown on the marginal land in Ontario, Canada, is used for producing biocarbon. Then PP is reinforced with biocarbon for producing biocomposite and the automotive components. The functional unit is considered to be an automotive component (441 cm3). Among the materials used in automotive components, colorant has the highest environmental impacts for each unit mass, followed by Miscanthus fiber, PP, talc, and biocarbon, respectively. Interestingly, each unit mass of biocomposite has slightly greater environmental impacts compared with composite. However, the innovative component is emerged to be environmentally favorable over the conventional component. The global warming potential (GWP) of innovative components and conventional components are 11.08 kg CO 2 eq. and 12.53 kg CO 2 eq., respectively. Consequently, any replacement of conventional components with innovative components would lead to meeting the fuel economy emission regulations of the automotive industries. • Life cycle impacts of biocarbon from miscanthus has been determined. • Evaluated environmental impacts of biocarbon & talc reinforced automotive components. • Biocarbon reinforced automotive component is favorable compared to its counterpart. [ABSTRACT FROM AUTHOR]