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Additive manufacturing processes allow for precise and efficient production, but it is estimated that one-third of the materials used results in waste. Further improvement in a sustainable perspective could come from the ability to manage these scraps and from the exploration of different routes for recovery and reuse. The Selective Laser Sintering process is particularly sensitive to this issue due to the waste ratio which can reach a very high quantity of not-sintered virgin powders. In this research study, recovered PA12 powders, preliminarily characterized through thermal and mechanical analysis, were mixed with 15% basalt powder to improve their aspect and thermomechanical resistance. The influence of basalt powder (BP) on mechanical properties as well as on the thermal stability of polyamide12 (PA12) powder composites was investigated. A study conducted on mechanical properties showed that polymeric composites' stiffness and hardness were influenced by adding filler, thus improving mechanical parameters. On the other hand, the application of thermogravimetric analysis allowed us to determine the composite's thermal stability. The objective is to obtain a recovered fully biobased material that could be used to substitute the petroleum-derived polymeric ones currently employed in the production of interiors and shells in the automotive sector. [ABSTRACT FROM AUTHOR]

Since the emergence of microplastics, the scientific community has been extremely alarmed regarding their potential risks for and threats to both the environment and human lives. MPs are traced in freshwater and marine environments, day-to-day-life ecosystems, and the bodies of animals and humans. Due to their usage advancements, MPs have become directly or indirectly an integral part of personal care, cosmetics, and cleaning products and appeared as a domestic cause of environmental pollution. Over the years, researchers have ascertained the harmful effects of MPs on the environment. In this regard, the monitoring and assessment of MPs in PCCPs necessitates considerable attention. The worldwide ban legislation on plastic μBs used in cosmetic products has driven researchers to investigate sustainable and eco-friendly alternatives. This review paper summarizes the potential threats of MPs used in cosmetics and the utilization of potential alternatives. [ABSTRACT FROM AUTHOR]

There is a growing need for resilient and renewable materials to aid society in global sustainability. It is incumbent upon the agricultural and manufacturing industries to work together to achieve this vision. In particular, the hemp plant has been identified as an emerging industrial crop that will be pivotal in achieving the United Nations Sustainable Development Goals. However, this nascent industry has received an influx of research and development activity, resulting in various methods and practices globally, challenging the repeatability of results, research advancement, standards development, and sustainability assessment. A systematic literature review is conducted to identify and document (1) the various practices for harvesting and converting industrial hemp into materials and products and (2) existing hemp-derived products and those under development. Using the PRISMA methodology, 5295 articles were identified, and 109 articles were included for review. Unlike prior reviews focusing on specific hemp plant components, materials, or products, this study systematically evaluates the utilization pathways of the whole plant (stalk, flower, leaf, and seed) to traditional, industrial, and emerging products. Further, myriad opportunities for hemp material and product applications, sustainability performance assessment, and future research are discussed. This review will benefit future hemp research, advancing process technologies, developing novel products, establishing policies and standards, and assessing sustainability performance.

Facile fabrication, low material complexity and closed‐loop recycling are essential for polymer plastics to alter their linear product economy towards a cradle‐to‐cradle one. Covalent adaptable networks (CANs) are one way to achieve that, which intrinsically exhibit decent mechanical properties like the thermosets but could also be easily recycled like the thermoplastics. In this work, we introduce rigid ester structural motifs into dynamic poly(disulfide)s to form a series of dual polymer networks. Owning to the coherence of soft/rigid segments and the reversible sacrificial crosslinking, they exhibit tailorable mechanical properties and good resistance towards different chemicals. Their closed‐loop recycling is achieved via mild solvolysis, maintaining materials' mechanical integrities. It offers a solution as a sustainable replacement for engineering plastics which are massively under production but hard to be recycled. [ABSTRACT FROM AUTHOR]

There is a growing need for resilient and renewable materials to aid society in global sustainability. It is incumbent upon the agricultural and manufacturing industries to work together to achieve this vision. In particular, the hemp plant has been identified as an emerging industrial crop that will be pivotal in achieving the United Nations Sustainable Development Goals. However, this nascent industry has received an influx of research and development activity, resulting in various methods and practices globally, challenging the repeatability of results, research advancement, standards development, and sustainability assessment. A systematic literature review is conducted to identify and document (1) the various practices for harvesting and converting industrial hemp into materials and products and (2) existing hemp-derived products and those under development. Using the PRISMA methodology, 5295 articles were identified, and 109 articles were included for review. Unlike prior reviews focusing on specific hemp plant components, materials, or products, this study systematically evaluates the utilization pathways of the whole plant (stalk, flower, leaf, and seed) to traditional, industrial, and emerging products. Further, myriad opportunities for hemp material and product applications, sustainability performance assessment, and future research are discussed. This review will benefit future hemp research, advancing process technologies, developing novel products, establishing policies and standards, and assessing sustainability performance. [ABSTRACT FROM AUTHOR]

Arthropod pests cause significant problems in agricultural crops all around the world. As chemical pesticide use becomes less desired, there is a need for alternative methods of pest control. Inspired by the natural adhesiveness of arthropod trapping plants, we examined the effectiveness of adhesive droplets made from oxidised and cross-linked plant-derived oils for control of western flower thrips. Two filter paper droplet adhesiveness assays and three detached chrysanthemum leaf assays were carried out to test efficacy against thrips. Suspensions containing adhesive droplets and other constituents were applied to filter papers and leaves via spraying or dipping. On filter papers, droplets made from oxidised rice germ oil (RGO) of different sizes caught 40–93% of thrips. Droplets made of a mixture of sunflower, olive, and linseed oil (MIX) caught up to 94% of thrips. Likewise, adhesive droplet-treated filter papers showed higher thrips mortality than untreated or control solution-treated filter papers. On chrysanthemum leaves, thrips were caught by both RGO (up to 40%) and MIX droplets (up to 20%) and thrips damage and reproduction were reduced. On MIX-treated leaves, thrips mortality was also increased. Within treatments, droplets of different size classes occurred and larger droplets were more effective at catching thrips in general. Droplets were also robust to rinsing with water, which is of importance for their application in horticulture. In conclusion, adhesive droplets made from edible plant oils show potential for use in control of western flower thrips. [ABSTRACT FROM AUTHOR]

Environmental issues, including climate change and plastic pollution, have compelled scientists to look at alternatives to traditional polymers. Scientists are actively researching biobased hyperbranched polymers, an emerging group of highly branched polymers made from sustainable resources. They are seen as a promising alternative to petrochemical-based polymers. Hyperbranched polymers can be made using single- and double-monomer techniques. This review provides an extensive perspective of the synthesis and properties of biobased hyperbranched polymers made from a variety of renewable starting materials, including starch, lignin, vanillin, levulinic acid, furfurylamine, ferulic acid, citric acid, adipic acid, succinic acid, and tannic acid and various vegetable oils have been investigated till date. Most of these biobased hyperbranched polymers have been created using vegetable oil as their raw materials because numerous vegetable oil derivatives like monoglycerides, polyols, and fatty acids can be potentially used as monomers for the polymer. In the paper, specifics about modified biobased hyperbranched polymers, their composites, nanocomposites, and functionalized versions are highlighted. These materials belong to a class that combines the special characteristics of hyperbranched polymers with the reinforcing and functionalizing effects of fillers like silver, carbon, silicone, clay, etc. Lastly, the paper also discusses the various practical applications of biobased hyperbranched polymers in various industrial sectors and their prospects for the future. [ABSTRACT FROM AUTHOR]

We report the use of novel biobased plasticizers prepared starting from citric acid (CA) in polylactic acid (PLA). Citric acid based plasticizers are well-known softeners for PLA, with citrate esters as the most commonly used class. However, citrate esters are known to leach out of the plastic material over time. This problem is currently addressed by acetylating the tertiary hydroxyl group of citric acid via complex and environmentally polluting processes. An alternative strategy consists in the reductive removal of the tertiary hydroxyl group, resulting in propane-1,2,3-tricarboxylic acid. Derivatizing this compound leads to novel plasticizers which have not been tested in PLA yet. Here, different esters of propane-1,2,3-tricarboxylic acid were synthesized and blended in PLA. Their influence on the thermal (Tg and Tm) and the mechanical properties (Young's modulus, stress and strain) of PLA along with their migration out of the material were compared to those of commercially available citric acid based plasticizers. Our results show that similar or better results were obtained with these new PLA plasticizers. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) is recognized as the primary cause of global warming due to its greenhouse potential. It plays a significant role in contributing to the emissions arising from a variety of anthropogenic activities, such as energy production, transportation, the construction industry, and other industrial processes. Capturing and utilizing CO2 to mitigate its impact on the environment is, therefore, of significant importance. To do so, strategies such as net-zero strategies, deploying capture and storage technologies, and converting CO2 into useful products have been proposed. In this review, we focused our attention on the preparation and performance of polymeric and crystalline materials for efficient CO2 capture. More precisely, we examined MOFs, petroleum-based polymers (amine-based, polymeric ionic liquid, ionic polymer, conjugated macro/micro-cyclic polymer, and porous organic polymer) as well as bio-based polymers for CO2 capture. In brief, the present work aims to guide the reader on the available crafted polymeric and crystalline materials offering a promising avenue towards innovative carbon dioxide capture strategy. [ABSTRACT FROM AUTHOR]

Poly(butylene 2,5‐thiophenedicarboxylate) (PBTh) is a novel biobased semicrystalline polyester with superior thermal, mechanical, and gas barrier properties; however, the crystallization kinetics and melting behavior of PBTh have not been studied in detail so far. The crystallization kinetics of PBTh was first studied in this research. The Ozawa equation failed to describe the nonisothermal melt crystallization kinetics of PBTh due to the secondary crystallization. The crystallization activation energy value was calculated by the Friedman method, which was negative and exhibited the conversion dependence. The isothermal melt crystallization kinetics of PBTh was well described by the Avrami equation in a wide range of crystallization temperature from 84 to 120 °C. PBTh showed the fastest crystallization rate at 104 °C; moreover, the Avrami exponent value slightly varied between 2.2 and 2.7, suggesting the same crystallization mechanism within the investigated temperature range. PBTh displayed one or two melting endotherms depending on crystallization temperature, which was well explained by the melting, recrystallization, and remelting mechanism. In addition, the equilibrium melting point of PBTh was estimated to be 163.1 °C with the Hoffmann−Weeks equation. [ABSTRACT FROM AUTHOR]

Studies on self-binding hot-pressed fiberboards using agricultural byproducts aim to identify alternatives to scarce wood resources. Particle size and mixture significantly impact strength, although direct comparisons are difficult due to differences in study methods. We evaluated fiberboards made from the two perennial biomass crops Miscanthus and Paulownia and compared them to Picea (spruce), using five distinct particle size blends prepared from milled and sieved particles, respectively. The boards were evaluated for their modulus of elasticity, modulus of rupture, reaction to fire, water absorption, and thickness swelling. All specimens exhibited normal ignitability, as defined by Euroclass E according to EN13501-1. The results indicate that mechanical performance improves with increasing density, which correlates with higher proportions of finer particles. Notably, the finer Miscanthus blends and all Paulownia samples met the modulus of elasticity requirements of EN 622. [ABSTRACT FROM AUTHOR]

Currently, the composite industry is focusing on more environmentally friendly resources in order to generate a new range of biobased materials. In this manuscript, we present a new work using lignocellulosic wastes from the paper industry to incorporate into biobased epoxy systems. The manufactured materials were composed of kraft lignin, glass fiber, and a sustainable epoxy system, obtaining a 40% biobased content. Using a vacuum infusion process, we fabricated the composites and analyzed their mechanical and UV resistance properties. The findings reveal a significant correlation between the lignin content and flexural modulus and strength, showing an increase of 69% in the flexural modulus and 134% in the flexural strength with the presence of 5% of lignin content. Moreover, it is necessary to highlight that the presence of synthesized lignin inhibits the UV degradation of the biobased epoxy coating. We propose that the use of lignocellulosic-based wastes could improve the mechanical properties and generate UV resistance in the composite materials. [ABSTRACT FROM AUTHOR]

This study explores the synthesis and performance of novel copolyesters containing 2,3-butanediol (2,3-BDO) as a biobased secondary diol. This presents an opportunity for improving their thermal properties and reducing crystallinity, while also being more sustainable. It is, however, a challenge to synthesize copolyesters of sufficient molecular weight that also have high 2,3-BDO content, due to the reduced reactivity of secondary diols compared to primary diols. Terephthalate-based polyesters were synthesized in combination with different ratios of 2,3-BDO and ethylene glycol (EG). With a 2,3-BDO to EG ratio of 28:72, an Mn of 31.5 kDa was reached with a Tg of 88 °C. The Mn dropped with increasing 2,3-BDO content to 18.1 kDa for a 2,3-BDO to EG ratio of 78:22 (Tg = 104 °C) and further to 9.8 kDa (Tg = 104 °C) for the homopolyester of 2,3-BDO and terephthalate. The water and oxygen permeability both increased significantly with increasing 2,3-BDO content and even the lowest content of 2,3-BDO (28% of total diol) performed significantly worse than PET. The incorporation of 2,3-BDO had little effect on the tensile properties of the polyesters, which were similar to PET. The results suggest that 2,3-BDO can be potentially applied for polyesters requiring higher Tg and lower crystallinity than existing materials (mainly PET). [ABSTRACT FROM AUTHOR]

In this study, the integration of paper industry waste with high cellulose content into biocomposites of polylactic acid (PLA), a widely used biobased polymer material, was investigated. The PLA/waste biocomposite samples (0–25 wt.%) were manufactured using the extrusion and injection moulding techniques. The mechanical test results showed improvements in terms of tensile properties and a decrease in impact strength as the percentage of residue increased. The melting temperature decreased, and the crystallinity increased in all biocomposites according to the Differential Scanning Calorimetry (DSC) analysis. Water absorption increased proportionally with the percentage of residue, attributed to the higher cellulose content in the biocomposites, determined by Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques. The scanning electron microscopy (SEM) fracture analysis demonstrated effective reinforcement–matrix cohesion, supporting the previously observed behaviour of the analysed materials. This work highlights the potential of using waste from the paper industry as reinforcement in PLA matrices, opening new perspectives for sustainable applications in the framework of the manufacture of composite materials. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) is recognized as the primary cause of global warming due to its greenhouse potential. It plays a significant role in contributing to the emissions arising from a variety of anthropogenic activities, such as energy production, transportation, the construction industry, and other industrial processes. Capturing and utilizing CO2 to mitigate its impact on the environment is, therefore, of significant importance. To do so, strategies such as net-zero strategies, deploying capture and storage technologies, and converting CO2 into useful products have been proposed. In this review, we focused our attention on the preparation and performance of polymeric and crystalline materials for efficient CO2 capture. More precisely, we examined MOFs, petroleum-based polymers (amine-based, polymeric ionic liquid, ionic polymer, conjugated macro/micro-cyclic polymer, and porous organic polymer) as well as bio-based polymers for CO2 capture. In brief, the present work aims to guide the reader on the available crafted polymeric and crystalline materials offering a promising avenue towards innovative carbon dioxide capture strategy.

The present chapter focuses on the recyclability of both renewable and biodegradable plastics, considering the recovery of matter (mechanical or chemical recycling) from the polymeric materials currently most diffused on the market. Biobased and compostable plastics are carbon neutral; thus, they do not contribute significantly to greenhouse gas (GHG) emissions. Nevertheless, recycling can be beneficial because it allows a prolongation of the material life cycle so that carbon is stored for a longer time up to the final composting. The chemical or mechanical recycling option is linked both to the possibility of reprocessing bioplastics without detrimental loss of properties as well as to the capability of selecting homogenous fractions of bioplastics after waste collection. Moreover, the different structural features of biodegradable bioplastics have resulted in different chemical recycling opportunities and also in different behaviors during the reprocessing operations necessary for recycling. All these aspects are discussed systematically in this review, considering biodegradable bioplastics, their blends and composites with natural fibers.

In order to contribute to the shift from petro-based chemistry to biobased chemistry, necessary to minimize the environmental impacts of the chemical industry, 2-methoxy-4-vinylphenol (4-vinyl guaiacol, 4VG) was used to synthesize a platform of biobased monomers. Thus, nine biobased monomers were successfully prepared. The synthesis procedures were investigated through the green metrics calculations in order to quantify the sustainability of our approaches. Their radical homopolymerization in toluene solution initiated by 2,2′-azobis(2-methylpropionitrile) (AIBN) was studied and the effect of residual 4VG as a radical inhibitor on the kinetics of polymerization was also explored. The new homopolymers were characterized by proton nuclear magnetic resonance (1H-NMR) spectroscopy, size exclusion chromatography and thermal analyses (dynamical scanning calorimetry DSC, thermal gravimetric analysis TGA). By varying the length of the alkyl ester or ether group of the 4VG derivatives, homopolymers with Tg ranging from 117 °C down to 5 °C were obtained. These new biobased monomers could be implemented in radical copolymerization as substitutes to petro-based monomers to decrease the carbon footprint of the resulting copolymers for various applications. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) has revolutionised the manufacturing industry, offering versatile capabilities for creating complex geometries directly from a digital design. Among the various 3D printing methods for polymers, vat photopolymerisation combines photochemistry and 3D printing. Despite the fact that single-epoxy 3D printing has been explored, the fabrication of multi-material bioderived epoxy thermosets remains unexplored. This study introduces the feasibility and potential of multi-material 3D printing by means of a dual-vat Digital Light Processing (DLP) technology, focusing on bioderived epoxy resins such as ELO (epoxidized linseed oil) and DGEVA (vanillin alcohol diglycidyl ether). By integrating different materials with different mechanical properties into one sample, this approach enhances sustainability and offers versatility for different applications. Through experimental characterisation, including mechanical and thermal analysis, the study demonstrates the ability to produce structures composed of different materials with tailored mechanical properties and shapes that change on demand. The findings underscore the promising technology of dual-vat DLP technology applied to sustainable bioderived epoxy monomers, allowing sustainable material production and complex structure fabrication. [ABSTRACT FROM AUTHOR]

The present chapter focuses on the recyclability of both renewable and biodegradable plastics, considering the recovery of matter (mechanical or chemical recycling) from the polymeric materials currently most diffused on the market. Biobased and compostable plastics are carbon neutral; thus, they do not contribute significantly to greenhouse gas (GHG) emissions. Nevertheless, recycling can be beneficial because it allows a prolongation of the material life cycle so that carbon is stored for a longer time up to the final composting. The chemical or mechanical recycling option is linked both to the possibility of reprocessing bioplastics without detrimental loss of properties as well as to the capability of selecting homogenous fractions of bioplastics after waste collection. Moreover, the different structural features of biodegradable bioplastics have resulted in different chemical recycling opportunities and also in different behaviors during the reprocessing operations necessary for recycling. All these aspects are discussed systematically in this review, considering biodegradable bioplastics, their blends and composites with natural fibers. [ABSTRACT FROM AUTHOR]

The ubiquitous nature of polymers has led to a widespread demand for sustainable polymers in numerous industrial applications. However, a lack of well laid out guidelines, product development pathways and certifications has resulted in a lot of commotions and confusions within the polymer value chain. Herein, a meticulous review is conducted on the topic of polymer sustainability shedding light on the standards, product declarations, biobased-biomass concepts, product carbon footprint, etc. It is critical that companies significantly contribute to such sustainability efforts in lieu of market readiness and competitive advantages. Any discussion within the sustainability horizon references a couple of terms/abbreviations/concepts. In this article, such key terminologies and concepts related to polymer sustainability are reviewed with a holistic outlook on the widespread approaches within the polymer sustainability horizon. In the polymer raw material manufacturers, the mass balance approach has gained more momentum with International Sustainability and Carbon Certification (ISCC). Product carbon footprint, life cycle analysis and third-party certifications were noted as the three key factors of sustainability engagement, with polymer manufactures placing sustainability commitments and targets for carbon emissions control. It is foreseen that a collaborative network between academic research, raw material manufacturers and the upstream companies and consumers will drive the sustainable polymer products market. [ABSTRACT FROM AUTHOR]

This comprehensive and critical review explores the synthesis and applications of carbohydrate‐based surfactants within the biorefinery concept, focusing on biobased sugar‐head molecules suitable for use across several manufacturing sectors, including cosmetics, pharmaceuticals, household products, detergents, and foods. The main focus relies on sustainable alternatives to conventional surfactants, which could reduce the final manufacturing carbon footprint of several industrial feedstocks and products. A thorough analysis of raw materials, highlighting the significance of feedstock sources, and the current biobased surfactants and rhamnolipid biosurfactants production trends, is presented. Key organic reactions for the production of sorbitan esters, sucrose esters, alkyl polyglycosides, and fatty acid glucamines, such as glycosidation, acylation, and etherification, as well as the production of rhamnolipids through fermentation are described. Given the scarce literature on the characterization of these surfactant types within the hydrophilic–lipophilic deviation (HLD) framework, the surfactant contribution parameter (SCP) in the HLD equation for sugar‐head surfactants is critically assessed. The economic landscape is also discussed, noting the significant growth in the biobased surfactants and biosurfactant market, driven by environmental awareness and regulatory changes, with projections indicating a substantial market increase in the forthcoming years. Finally, the promising potential of generative artificial intelligence (AI) in developing customized surfactant molecules, with optimized properties for targeted applications, is emphasized as a promising avenue for future research. [ABSTRACT FROM AUTHOR]

The feasibility of producing biobased Polybutylene adipate terephthalate (PBAT) or 1,4-butanediol (BDO) as a way for diversification of sugar production facilities, was investigated in this study. Two scenarios for biorefineries integrated into an existing sugarcane mill, were investigated: In scenario 1, the feedstock (A-molasses) was diverted to produce three different monomers, i.e., terephthalic acid (TPA), adipic acid (AA) and 1,4-butanediol (BDO) in stoichiometric ratios required for PBAT production. Scenario 2 investigated using all the feedstock to produce BDO as a final product, based on substantial market potential. The processes were simulated in Aspen Plus® to obtain mass and energy balances for equipment sizing and costing. Then a discounted cash flow method was used to calculate the internal rate of return (IRR). The results indicated that scenario 1 had higher energy usage (47.3 MJ/kg of PBAT) compared to scenario 2 (42.1 MJ/kg of BDO) as PBAT synthesis required TPA and AA monomers, produced in energy-intensive processes. Scenario 2 with an IRR of 34.4% had a better economic performance than Scenario 1 with 19.1% IRR, partly due to Scenario 1 having smaller production scales for monomers, suffering the negative effects of economies-of-scale. Although both scenarios were profitable, the sensitivity analysis indicated that Scenario 1 would remain profitable with either a 30% increase in total capital investment or a 30% decrease in operation time, while Scenario 2 would become unprofitable. The study has demonstrated that bio-based PBAT can be produced from molasses in a manner that is cost-competitive with current fossil-based market prices. [ABSTRACT FROM AUTHOR]

Dried porous materials can be found in a wide range of applications. So far, they are mostly prepared from inorganic or indigestible raw materials. The aim of the presented study was to provide a proof of concept for (a) the suitability of mealworm protein gels to be turned into dried porous biomaterials by either a combination of solvent exchange and supercritical drying to obtain aerogels or by lyophilization to obtain lyophilized hydrogels and (b) the suitability of either drying method to retain trace elements such as zinc in the gels throughout the drying process. Hydrogels were prepared from mealworm protein, subsequently dried using either method, and characterized via FT-IR, BET volume, and high-resolution scanning electron microscopy. Retention of zinc was evaluated via energy-dispersive X-ray spectroscopy. Results showed that both drying methods were suitable for obtaining dried porous biomaterials and that the drying method mainly influenced the overall surface area and pore hydrophobicity but not the secondary structure of the proteins in the gels or their zinc content after drying. Therefore, a first proof of concept for utilizing mealworm protein hydrogels as a base for dried porous biomaterials was successful and elucidated the potential of these materials as future sustainable alternatives to more conventional dried porous materials. [ABSTRACT FROM AUTHOR]

Plastic mulches made from nonbiodegradable polymers (e.g., polyethylene) provide an essential service in commercial horticultural production systems by enhancing crop productivity through weed suppression, soil moisture conservation, and moderating soil and canopy temperature conditions. Plastic mulches are particularly important in organic agriculture because weed management options are limited. Nevertheless, there is increasing concern about addressing the negative environmental impacts of plastic mulch waste. Soil-biodegradable plastic mulch (BDM) films that are designed to biodegrade in soils after incorporation are promising alternatives to nonbiodegradable plastic mulch. However, although the US organic standards technically permit the use of BDM films, no commercially available products meet National Organic Program (NOP) requirements for 100% biobased content and 90% degradation after 2 years following soil incorporation (7 Code of Federal Regulations, section 205.2). Other concerns about biodegradable film mulches include high perceived cost, esthetics, and uncertainties regarding the impacts of soil incorporation. New mulch technologies have emerged to diversify sustainable mulch options and overcome barriers associated with BDM film use in organic production. The objective of this study was to provide an overview of alternative and emerging mulch technologies, with an emphasis on biodegradable mulches, including water-based sprayable mulches such as hydromulch and foam mulch, and biobased agrotextiles. Information about how these mulch technologies contribute to organic and sustainable agriculture is provided, along with definitions, opportunities, challenges, and recommended areas for future research.

This article deals with a detailed experimental study dedicated to the evaluation of the overall mechanical behaviour of a bio-based composite structure used in transportation industries. The sandwich structure is designed to increase the lightening, vibration damping, and composite recyclability. The considered materials consist of a Flax/Elium® laminate composite for skins associated with a balsa core. The sandwich structure was obtained using a one-shot liquid resin infusion process. Low-velocity impact tests were carried out on different sandwich configurations with the aim of characterizing the effects of the stacking sequence and the density and thickness of the core. Furthermore, an experimental comparative analysis was conducted involving two composite laminate types: Glass/Elium and Flax/Elium to enhance the specific behaviour of flax fibre composite to be used as skins in the sandwich structures. The impact tests were carried out at low velocities and at different levels of impact energy using a drop-weight test bench. Notable damage mechanisms have been identified, and a chronological sequence of their development has been suggested. Ultrasonic analyses using C-Scan imaging were applied to the opposite side of the impacted specimen. The research proves the efficient energy-absorbing capability of the biobased sandwich structure during impact. Finally, this study enables a deeper understanding of various parameters that influence the behaviour of sandwiches during low-velocity impacts, thereby facilitating more informed material selection for practical applications.

The study successfully developed thermoset materials utilizing acrylate epoxidized soybean oil (AESO) and allyl cinnamate (ACIN) with tert-butyl peroxybenzoate (TBPB) as the initiator. Isothermal curing at temperatures between 110 °C to 140 °C of the developed formulations, showed that higher temperatures accelerated the conversion process. The higher curing temperature increased the degree of conversion, leading to obtain the best flexural strength for samples cured at 130 °C. However, samples cured at 120 °C exhibited better impact properties due to a lower degree of conversion, which allows for a more mobile reticular network. In addition, morphological observations confirmed these mechanical property trends. Dynamic thermal characterization revealed changes in glass transition temperature and exothermic reactions due to unreacted products appeared for materials cured at low temperature. Increasing curing temperature allowed to enhance thermal stability by increasing molecular weight. Finally, thermomechanical analysis confirmed stiffness and glass transition temperature increases observed during flexural tests and thermal characterization.

Biobased composite films have been prepared by solvent cast and hot press methods using saturated aliphatic polyester (expressed as HP1) with different loading (i.e., 1 and 3 wt %) of CNF, citrus fiber, and dextrin. HP1 was prepared by acyclic diene metathesis (ADMET) polymerization of biobased α,ω-dienes of bis(undec-10-enoate) with isosorbide (M1) using a RuCl2(IMesH2)(CH-2–OiPr–C6H4) (HG2, IMesH2 = 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene) catalyst and subsequent tandem hydrogenation (H2 2.0 MPa, 50 °C, 12 h). The appearance (morphology, transmittance, haze), the thermal properties (including degree of crystallinity by DSC thermograms), and the tensile properties of the fabricated films were evaluated to explore effect of the additives. The prepared composite films by solvent cast and hot press methods were transparent and showed enhancement of tensile strength. The citrus fiber, upcycled product made from the waste residue of squeezed citrus juice and oil, among the other additives showed the highest tensile strength and toughness values irrespective of the molecular weight of the employed polyester or the used fabrication method. [ABSTRACT FROM AUTHOR]

Development of biobased aliphatic polyesters with better mechanical (tensile) properties in film has attracted considerable attention. This report presents the synthesis of soluble network biobased aliphatic polyesters by acyclic diene metathesis (ADMET) polymerization of bis(undec-10-enyl)isosorbide diester [M1, dianhydro-D-glucityl bis(undec-10-enoate)] in the presence of a tri-arm crosslinker [CL, glycerol tris(undec-10-enoate)] using a ruthenium–carbene catalyst, and subsequent olefin hydrogenation using RhCl(PPh3)3. The resultant polymers, after hydrogenation (expressed as HCP1) and prepared in the presence of 1.0 mol% CL, showed better tensile properties than the linear polymer (HP1) with similar molecular weight [tensile strength (elongation at break): 20.8 MPa (282%) in HP1 vs. 35.4 MPa (572%) in HCP1]. It turned out that the polymer films prepared by the addition of CL during the polymerization (expressed as a 2-step approach) showed better tensile properties. The resultant polymer film also shows better tensile properties than the conventional polyolefins such as linear high density polyethylene, polypropylene, and low density polyethylene. [ABSTRACT FROM AUTHOR]

Superabsorbent composites (SC) can be defined as filler-enriched absorbent polymer chemistry. The superabsorbent polymers are made up of hydrophilic polymers with added cross-linking systems and tend to absorb, swell and retain a substantial volume of water. The conventional chemistries are based on synthetic polymers mainly acrylics. Concerning the fossil fuel crisis, their price depletion and to make the superabsorbent compounds more eco-friendly various biobased materials are incorporated into the structure to make the systems eco-friendlier and more sustainable. The biobased compounds widely explored in such areas are starch, cellulose, guar gum, xanthan gum, alginate, etc. The filler namely various clays such as montmorillonite (MMT), Attapulgite (APT), Kaolin, and bentonite in carbon-based fillers carbon nanotubes (CNT), graphite oxide, and various biobased compounds such as proteins, and biobased waste such as wheat straw, rice husk ash, and miscellaneous fillers as semi-coke, layered double hydroxides are well studied in the SC area. The performance of SC depends upon various reaction parameters such as monomers, initiator, modifier, filler, temperature, and time as well on other factors such as pH of the medium and particle size. The SC is found in a variety of application areas such as drug delivery, agriculture, wastewater treatment, the construction industry, sanitary napkins and diapers, food preservation, and artificial snow. [ABSTRACT FROM AUTHOR]

Biopolymers, especially cellulose, are vital to transitioning to a circular economy and reducing our reliance on fossil fuels. However, for many applications a high degree of cellulose hydroxyl modification is necessary. The challenge is that the chemical features of the hydroxyls of cellulose and water are similar. Therefore, chemical modification of cellulose is often explored under non‐aqueous conditions with systems that result in high hydroxyl accessibility and reduce cellulose aggregation. Unfortunately, these systems depend on hazardous and complex solvents from fossil resources, which diverge from the initial sustainability objectives. To address this, we developed three new betaine‐based ionic liquids that are fully bio‐based, scalable, and green. We found that a specific ionic liquid had the perfect chemical features for the chemical activation of cellulose without disturbing its crystalline ordering. The high activation in heterogeneous conditions was exemplified by reacting cellulose with succinic anhydride, resulting in more than 30 % conversion of all hydroxyls on cellulose. Overall, this work opens new perspectives for the derivatization of cellulosic materials while simultaneously "keeping it green". [ABSTRACT FROM AUTHOR]

Poly (lactic acid), PLA, a commercially available thermoplastic derived from plant sugars, finds increasing applications in consumer products, disposable packaging, textiles, etc. However, the widespread applications of this bioplastic are limited by its brittleness. This preliminary study inspired a structural analogy with the structure of triglycerides with arms having the nature of PLA itself. Biobased tri-armed toughening additives were synthesized with two oligo (lactic acid) arm lengths. Bio-based resins, or bioresins, are derived from renewable resources such as vegetables. The oligomeric bioresins were characterized by Fourier transform infrared (FTIR) and Nuclear Magnetic Resonance (1 H-NMR and 13 C-NMR) spectroscopies. Easy-to-use green chemistry metrics and simplified life-cycle assessment, i.e., EcoScale and GREEN MOTION scales, were also considered to provide an opening insight into the efficiency and greenness of the processes used to prepare the bioresins. The modifying bioresins (with dosages of 10 and 20 wt%) were blended with PLA to prepare the modified films. Crystallization, mechanical, and thermal properties of the films were evaluated by XRD, tensile experiments, DSC, and TGA apparatuses. The results showed that adding the modifiers improved the flexibility and mechanical properties of the PLA films. The migration and the water vapor permeability tests revealed that the modified films exhibited good resistance against the modifier migration. Overall, this preliminary study indicated a promising modification of the bioplastic PLA using entirely biobased oligomers of its own nature that could be implemented by cost-effective, simple, and clean methods. The modified PLAs might be considered candidates for packaging and additive manufacturing applications. [ABSTRACT FROM AUTHOR]

This work addresses a novel bio-solvolysis process for the treatment of complex poly(ethylene terephthalate) (PET) waste using a biobased monoethylene glycol (BioMEG) as a depolymerization agent in order to achieve a more sustainable chemical recycling process. Five difficult-to-recycle PET waste streams, including multilayer trays, coloured bottles and postconsumer textiles, were selected for the study. After characterization and conditioning of the samples, an evaluation of the proposed bio-solvolysis process was carried out by monitoring the reaction over time to determine the degree of PET conversion (91.3–97.1%) and bis(2-hydroxyethyl) terephthalate (BHET) monomer yield (71.5–76.3%). A monomer purification process, using activated carbon (AC), was also developed to remove the colour and to reduce the metal content of the solid. By applying this purification strategy, the whiteness (L*) of the BHET greatly increased from around 60 to over 95 (L* = 100 for pure white) and the Zn content was significantly reduced from around 200 to 2 mg/kg. The chemical structure of the purified monomers was analyzed via infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC), and the composition of the samples was measured by proton nuclear magnetic resonance (1H-NMR), proving a high purity of the monomers with a BHET content up to 99.5% in mol. [ABSTRACT FROM AUTHOR]

Utilizing triethylenediamine (DA), 1,3-propanesultone (PS), whose ring opens during the formation of the dizwiterion-intermediate DA-2PS, and the metal chlorides XCly, where X = Sn(IV), Zn(II),Al(III), Fe(III) and Mn(II), are used for the synthesis of five kinds of acidic metal-based functionalized ionic liquid catalysts ([DA-2PS][XCly]2). Their chemical structures, thermal stability and dual acidic active site were analyzed. We investigated the performance of [DA-2PS][XCly]2 in catalyzing the esterification reaction between 2,5-furandicarboxylic acid (FDCA) and ethylene glycol (EG) to synthesize poly (ethylene 2,5-furandicarboxylate)(PEF). Among the catalysts tested, [DA-2PS][SnCl5]2 exhibited the best catalytic performance under identical process parameters, and the optimal catalyst dosage was determined to be 0.05 mol% based on FDCA. The optimal conditions for the reaction were predicted using response surface methodology: a feed ratio of EG:FDCA = 1.96:1, an esterification temperature of 219.86 °C, a polycondensation temperature of 240.04 °C and a polycondensation time of 6.3 h, with a intrinsic viscosity of 0.67 dL·g−1. The resulting PEF was experimentally verified to exhibit an intrinsic viscosity of 0.68 dL·g−1 and a number average molecular weight of 28,820 g·mol−1. Finally, the structure and thermal properties of PEF were characterized. The results confirmed that PEF possessed the correct structure, exhibited high thermal stability and demonstrated excellent thermal properties. [ABSTRACT FROM AUTHOR]

This work highlights the importance of renewable materials, specifically polymers derived from epoxidized oils, in promoting sustainable development and reducing the environmental impact of various industries. The use of carboxylic acids as hardeners for biobased resins from epoxidized oils is also discussed as a promising development in this field. However, there is a lack of research in this area, and finding the right combination of carboxylic acids and epoxidized oils remains a challenge. The present work aimed to address this gap by synthesizing biobased resins using epoxidized soybean oil (ESO) and dicarboxylic acids with specific aliphatic chain lengths, such as oxalic, succinic, adipic and sebacic acids with 0, 2, 4 and 8 carbons in aliphatic chain. The curing and properties of the resulting biopolymers were investigated using DSC, FTIR, TGA, and swelling ratio assessments. FTIR spectra evidenced that the reaction between epoxy and carboxylic groups occurred by the presence of ester groups, as verified after the disappearance of the epoxy bands at ~ 829 cm−1 and the appearance of related bands to hydroxyl (-OH) at ~ 3500 and ester at 1685–1742 cm−1, respectively. DSC scans presented exothermic peaks related to the curing reactions associated to an increasing enthalpy (ΔH) as the aliphatic chain size increases. The activation energy, Eac, estimated using Friedman and Vyazovkin approaches, is highly influenced by the chain size and pKa of the acids. Furthermore, the thermal and hydrocatalytic degradation increase with the decrease of aliphatic chain. The study also introduces oxalic acid as a biobased cross linker for ESO, which has not been so far combined without any synthetic modifications in its structure. [ABSTRACT FROM AUTHOR]

Currently, the composite industry is focusing on more environmentally friendly resources in order to generate a new range of biobased materials. In this manuscript, we present a new work using lignocellulosic wastes from the paper industry to incorporate into biobased epoxy systems. The manufactured materials were composed of kraft lignin, glass fiber, and a sustainable epoxy system, obtaining a 40% biobased content. Using a vacuum infusion process, we fabricated the composites and analyzed their mechanical and UV resistance properties. The findings reveal a significant correlation between the lignin content and flexural modulus and strength, showing an increase of 69% in the flexural modulus and 134% in the flexural strength with the presence of 5% of lignin content. Moreover, it is necessary to highlight that the presence of synthesized lignin inhibits the UV degradation of the biobased epoxy coating. We propose that the use of lignocellulosic-based wastes could improve the mechanical properties and generate UV resistance in the composite materials.

Stimulated by the growing interest in sustainable polymers, the past few decades have seen intensive research in the field of CO2-based polycarbonates. Within this research, the catalysts for the ring-opening copolymerization of epoxides and CO2 developed from early heterogeneous complexes to a wide variety of homogeneous catalysts. These complexes are continuously improved to meet growing expectations regarding activity and selectivity. Simultaneously, the range of epoxide monomers has steadily expanded due to the growing interest in biobased starting materials for polymers. The potential of the resulting aliphatic polycarbonates is evident in their thermal and mechanical properties, where they exhibit a wide range from soft to brittle and from low to high glass transition temperatures. Although the biodegradability of CO2-based polycarbonates has not yet been extensively researched, it has already been possible to gain knowledge about poly(propylene carbonate) and its compostability. The entire potential of aliphatic polycarbonates is still far from being fully discovered, and with constant development of new catalysts and monomer feedstocks, the chance of a CO2- and biobased polymer achieving greater industrial relevance is increasing. [ABSTRACT FROM AUTHOR]

Poly(lactic acid)/poly(butylene succinate‐co‐adipate) (PLA/PBSA) blends are found promising for film packaging applications because of their flexibility, resistance, and compostability. Industrially extruded granules and films based on PLA and containing different amounts of PBSA are reprocessed through mini‐extrusion, to simulate recycling, and tested in terms of their melt flow rate as a function of PBSA content. Moreover, pure PLA commercial granules and the film produced extruding the PLA/PBSA 60/40 blend are reprocessed several times by injection molding and characterized in terms of melt flow rate, mechanical properties, thermal properties, and color as a function of injection molding cycles. The variation in melt fluidity and thermo‐mechanical properties is negligible up to 3 injection molding cycles for both pure PLA granules and PLA/PBSA blend. In the case of blend the change in color (yellowing and darkening) is more evident and slight local compositional change in injection molded items can be evidenced as well as a slight decrease in PBS crystallinity as a function of injection molding cycles. Nevertheless, in applications where these aspects are not critical, these materials can be recycled by extrusion or injection molding before being composted, thus prolonging their life cycle and storing carbon in them as longer as possible. [ABSTRACT FROM AUTHOR]

Sustainability is a buzzword across numerous industries, and the polymer value chain is no exception. Due to the ubiquitous nature of polymer products, the conundrums and misconceptions revolving around them are universal too. In this review, we attempt to meticulously undertake some of the polymer-based sustainability conundrums and challenges, driven by technical knowledge and supported by facts. Four major topics of relevance are selected and reviewed without any bias. A basic understanding of all sustainability-related jargon is examined at the beginning to provide the necessary fundamental awareness. Thereafter, the emergence of biobased polymer products is critically analyzed against its distinct biodegradability conundrums. This is followed by an outlook and comparison of plastic products versus their alternatives. Greenwashing in the fashion industry is also reviewed in depth. Among the challenges, issues related to microplastics are assessed owing to their importance currently. It is critical that readers can understand the actual scenario and call out product propaganda with superficial claims. A meticulous overview of the existing literature and information is conducted to summarize all the conundrums, challenges, and future aspects. This examination of pertinent topics is carried out in the hope of spreading knowledge, enabling a higher critique within the polymer research community and a sustainable environment. [ABSTRACT FROM AUTHOR]

In order to contribute to the shift from petro-based chemistry to biobased chemistry, necessary to minimize the environmental impacts of the chemical industry, 2-methoxy-4-vinylphenol (4-vinyl guaiacol, 4VG) was used to synthesize a platform of biobased monomers. Thus, nine biobased monomers were successfully prepared. The synthesis procedures were investigated through the green metrics calculations in order to quantify the sustainability of our approaches. Their radical homopolymerization in toluene solution initiated by 2,2′-azobis(2-methylpropionitrile) (AIBN) was studied and the effect of residual 4VG as a radical inhibitor on the kinetics of polymerization was also explored. The new homopolymers were characterized by proton nuclear magnetic resonance (1H-NMR) spectroscopy, size exclusion chromatography and thermal analyses (dynamical scanning calorimetry DSC, thermal gravimetric analysis TGA). By varying the length of the alkyl ester or ether group of the 4VG derivatives, homopolymers with Tg ranging from 117 °C down to 5 °C were obtained. These new biobased monomers could be implemented in radical copolymerization as substitutes to petro-based monomers to decrease the carbon footprint of the resulting copolymers for various applications.

Dried porous materials can be found in a wide range of applications. So far, they are mostly prepared from inorganic or indigestible raw materials. The aim of the presented study was to provide a proof of concept for (a) the suitability of mealworm protein gels to be turned into dried porous biomaterials by either a combination of solvent exchange and supercritical drying to obtain aerogels or by lyophilization to obtain lyophilized hydrogels and (b) the suitability of either drying method to retain trace elements such as zinc in the gels throughout the drying process. Hydrogels were prepared from mealworm protein, subsequently dried using either method, and characterized via FT-IR, BET volume, and high-resolution scanning electron microscopy. Retention of zinc was evaluated via energy-dispersive X-ray spectroscopy. Results showed that both drying methods were suitable for obtaining dried porous biomaterials and that the drying method mainly influenced the overall surface area and pore hydrophobicity but not the secondary structure of the proteins in the gels or their zinc content after drying. Therefore, a first proof of concept for utilizing mealworm protein hydrogels as a base for dried porous biomaterials was successful and elucidated the potential of these materials as future sustainable alternatives to more conventional dried porous materials.

Abstract Poly(lactic acid)/poly(butylene succinate‐co‐adipate) (PLA/PBSA) blends are found promising for film packaging applications because of their flexibility, resistance, and compostability. Industrially extruded granules and films based on PLA and containing different amounts of PBSA are reprocessed through mini‐extrusion, to simulate recycling, and tested in terms of their melt flow rate as a function of PBSA content. Moreover, pure PLA commercial granules and the film produced extruding the PLA/PBSA 60/40 blend are reprocessed several times by injection molding and characterized in terms of melt flow rate, mechanical properties, thermal properties, and color as a function of injection molding cycles. The variation in melt fluidity and thermo‐mechanical properties is negligible up to 3 injection molding cycles for both pure PLA granules and PLA/PBSA blend. In the case of blend the change in color (yellowing and darkening) is more evident and slight local compositional change in injection molded items can be evidenced as well as a slight decrease in PBS crystallinity as a function of injection molding cycles. Nevertheless, in applications where these aspects are not critical, these materials can be recycled by extrusion or injection molding before being composted, thus prolonging their life cycle and storing carbon in them as longer as possible.

High biobased carbon content polyurethane dispersions (PUD) are a more sustainable alternative to conventional oil-derived waterborne dispersions in coatings. However, there are still many performance limitations from restricted availability of effective renewable monomers and oligomers. This work demonstrates the improvement of the properties of high biobased content PUD and derived coating by introducing a photo-reversibly crosslinkable coumarin as chain extender within the structure. The effect of partial substitution of 1,3-propanediol biobased by a di-hydroxy photo-reactive cyclic coumarin on the particle size and the stability was analyzed by dynamic light scattering (DLS) and multiple light scattering (MLS). The lateral and more rigid structure of coumarin involved a moderated increment in particle size without significant effect on the dispersion stability for at least 45 days. Associated improvement in hardness and toughness was also demonstrated by tensile test, pendulum hardness, pencil hardness and scratch resistance test. Furthermore, controlled UV irradiation of the polyurethane gave rise to a mechanical performance adjustment from reversible photo-crosslinking and scission of the coumarin molecules within the macromolecular structure. A 70% dimerization degree of the coumarin within the polyurethane film by UV light provided a partially reversible threefold higher tensile strength than that of the original biobased formulation as an effective tool to tune the response of biobased polyurethanes. [ABSTRACT FROM AUTHOR]

The increasing demand to provide sustainably produced plastic materials requires, a.o., the development of biobased flame retardants (FRs) for applications where flame retardancy is essential. To meet those challenging new sustainability requirements, a set of novel phosphorus-containing cellulose esters were synthesized by an efficient two-step procedure. In the first step, cellulose was treated with acrylic anhydride to synthesize acrylate-functionalized cellulose esters—more specifically, cellulose acrylate butyrate (CeAcBu) and propionate (CeAcPr). Subsequently, phosphorylated anhydro erythritol (PAHE), synthesized from the sugar alcohol erythritol, was added to the acrylate-functionalized cellulose esters via Phospha-Michael addition. For comparison a cellulose ester based on 6H-Dibenzo[c,e][1,2]oxaphosphorin-6-on (DOPO) was prepared analogously. The acrylate-functionalized cellulose esters and novel FRs were characterized by NMR spectroscopy. TGA investigations of PAHE-functionalized CeAcBu revealed an onset temperature of decomposition (2% mass loss) of approx. 290 °C. The novel PAHE-based FR was incorporated into a polypropylene-polyethylene copolymer (PP-co-PE) together with poly-tert-butylphenol disulfide (PBDS) (8 wt.%/2 wt.%) as a synergist. The PP-PE samples achieved V2 classification in the UL 94 V test. In addition, specimens of a rapeseed oil-based polyamide containing PAHE-functionalized CeAcBu at 20 wt.% loading yielded a V2 rating with short burning times. [ABSTRACT FROM AUTHOR]

Corrosion is a significant problem that negatively affects a wide range of structures and buildings, resulting in their premature failure, which causes safety hazards and significant economic loss. For this reason, various approaches have been developed to prevent or minimize the effects of corrosion, including corrosion inhibitors. Recently, biobased inhibitors have gained a certain interest thanks to their unique properties, eco-friendliness, and availability. Among all the green precursors, lignin is of particular interest, being a natural polymer that can be obtained from different sources including agricultural residues. Corrosion inhibitors based on ionic liquids (ILs) also present interesting advantages, such as low volatility and high tunability. If combined, it may be possible to obtain new lignin-based ILs that present interesting corrosion inhibitor properties. In this work, the inhibition properties of new biobased lignin ILs and the influence of anions and cations on the corrosion of mild steel in an aqueous solution of 0.01 M NaCl were investigated by Potentiostatic Electrochemical Impedance Spectroscopy (PEIS) and Cyclic Potentiodynamic Polarization (CPP). Moreover, the surface was characterized using SEM, EDS, and optical profilometry. The IL choline syringate showed promising performance, reducing the corrosion current after 24 h immersion in 0.01 M sodium chloride, from 1.66 µA/cm2 for the control to 0.066 µA/cm2 with 10 mM of the IL present. In addition to its performance as a corrosion inhibitor, both components of this IL also meet or exceed the current additional desired properties of such compounds, being readily available, and well tolerated in organisms and the environment. [ABSTRACT FROM AUTHOR]