Search Results (205)

This study investigates the influence of cellulose nanofibrils (CNFs) on the polymerization kinetics of methyl methacrylate (MMA) during in situ suspension polymerization at 70 °C (343.15 K). Four CNF concentrations were evaluated and compared to a reference system without CNFs. Polymerizations were carried out in a thermostatted flask immersed in an ethylene glycol bath and covered to ensure thermal stability. The temperature profiles of both the reaction medium and the surrounding bath were continuously recorded, allowing for the calculation of heat flow, polymerization rate (R_p), and monomer conversion. The incorporation of CNFs led to a significant increase in R_p and faster MMA conversion. This effect was attributed to the presence of nanocellulose within the polymerizing medium, which restricted diffusion and contributed to the onset of the phenomenon of autoacceleration. Additionally, CNFs promoted a higher total heat release, underscoring the need for thermal control during scale-up. The resulting material qualifies as a biocomposite, as biobased nanofibrils became integrated into the polymer matrix. These findings demonstrate that CNFs act as effective kinetic promoters in MMA polymerizations and may serve as functional additives to enhance both reaction performance and sustainability. However, safety considerations remain critical when transferring this approach to industrial processes. Full article

Benzoxazine resins are gaining attention for their impressive thermal stability, low water uptake, and strong mechanical properties. In this work, two new bio-based benzoxazine monomers were developed using renewable arbutin: one combined with 3-(2-aminoethylamino) propyltrimethoxysilane (AB), and the other with furfurylamine (AF). Both were synthesized using a simple Mannich-type reaction and verified through FT-IR and ¹H-NMR spectroscopy. By blending these monomers in different ratios, copolymers with adjustable thermal, dielectric, and surface characteristics were produced. Thermal analysis showed that the materials had broad processing windows and cured effectively, while thermogravimetric testing confirmed excellent heat resistance—especially in AF-rich blends, which left behind more char. The structural changes obtained during curing process were monitored using FT-IR, and XPS verified the presence of key elements like carbon, oxygen, nitrogen, and silicon. SEM imaging revealed that AB-based materials had smoother surfaces, while AF-based ones were rougher; the copolymers fell in between. Dielectric testing showed that increasing AF content raised both permittivity and loss, and contact angle measurements confirmed that surfaces ranged from water-repellent (AB) to water-attracting (AF). Overall, these biopolymers (AB/AF copolymers) synthesized from arbutin combine environmental sustainability with customizability, making them strong candidates for use in electronics, protective coatings, and flame-resistant composite materials. Full article

In the chemistry of bio-based furans, the Diels–Alder reaction plays an important role as a renewable route for the synthesis of fuels, fine chemicals, and monomers. Nonetheless, the unfavorable kinetic and thermodynamic parameters inherent to the Diels–Alder reaction involving furans as dienes often lead to the reversibility of cycloaddition, resulting in decreased equilibrium conversion and diastereoselectivity. In this study, we present a new strategy for overcoming the problem of reversibility in chemical reactions. We demonstrate that conducting the reaction under solvent-free conditions can facilitate the transition from a molten state formed by the initial reactants to a solid phase containing the reaction product along with an excess of the initial substrate. According to our results, such a liquid-to-solid transition of the reaction mixture can lead to exceptionally high conversion and diastereoselectivity in the furan–maleimide Diels–Alder reaction, particularly for challenging electron-poor furanic substrates. Our approach enables the reversible furan–maleimide Diels–Alder reaction to be performed in a cleaner and more environmentally friendly manner, free from the complexities associated with the use of solvents and the need for purification from side products. Full article

The removal of pharmaceutical contaminants like the anticonvulsant carbamazepine (CBZ) from water sources is a growing environmental challenge. This study explores the development of molecularly imprinted polymers (MIPs) tailored for CBZ adsorption using a bulk polymerization approach. Initially, this study focused on selecting the optimal cross-linker, comparing a trifunctional (trimethylolpropane triacrylate, TRIM) and a bifunctional cross-linker (ethylene glycol dimethacrylate, EGDMA) in combination with two common monomers (2-vinylpyridine and methacrylic acid). TRIM-based MIPs demonstrated superior adsorption efficiency and stability due to their higher cross-linking density. To improve sustainability, six bio-based monomers were investigated; of these, eugenol (EUG) and coumaric acid (COU) showed the best CBZ affinity due to π-π interactions and hydrogen bonding. Adsorption tests conducted in pharmaceutical-spiked real wastewater demonstrated that MIPs exhibit a high selectivity for CBZ over other pharmaceuticals like the anti-inflammatory drugs diclofenac (DCF) and ibuprofen (IBU), even at high concentrations. Reaction conditions were further optimized by adjusting the reaction time and the ratio between reagents to enhance selectivity and adsorption performance. These results highlight the potential of bio-based MIPs as efficient and selective materials for the removal of pharmaceutical pollutants from wastewater. Full article

Poly(lactic acid) (PLA) is a widely used biobased polyester which can be derived from renewable resources. Due to its excellent properties, it has already been adopted in various industrial sectors. While PLA is compostable, its degradation to the environment is very slow, necessitating the development of efficient recycling methods. This study focuses on the chemical recycling via microwave-assisted alkaline hydrolysis of PLA and its copolymers with poly(ethylene azelate) (PEAz), aiming to recover both carboxylic acid monomers: lactic acid and azelaic acid. Moreover, our method tunes the degradation of PLA via the synthesis of the novel aliphatic PLA-based copolyesters, targeting engineering-like applications, specifically in the field of printed electronics. Various process parameters were analyzed, including the temperature and the duration of the experiments as well as different phase transfer catalysts. Complete degradation was achieved at low temperatures (110–125 °C) and short times (12–15 min) for the PLA-based copolyesters, offering significant environmental benefits, as considerably less energy is consumed compared to chemical conventional methods. So, by changing the composition of the copolyesters through the incorporation of PEAz blocky segments, the ester bonds became more susceptible to hydrolysis under alkaline conditions assisted with microwave irradiation. Additionally, enzymatic hydrolysis was also studied in parallel for comparative purposes, revealing low degradation rates, thus establishing the microwave-assisted alkaline hydrolysis as a solid and reliable method for tuning the degradation of PLA-based materials. Full article

The need for renewable alternatives to petroleum-based polymers is growing in response to environmental concerns and resource depletion. Polyimides (PIs), which are traditionally synthesized from petroleum-derived monomers, raise sustainability issues. In this work, renewable 2,5-furandicarboxylic acid (FDCA) was employed as a sustainable feedstock to synthesize a bio-based diamine monomer, N,N′-bis(4-aminophenyl)furan-2,5-dicarboxamide (FPA). Subsequently, FPA was polymerized with various aromatic dianhydrides through thermal imidization, yielding four distinct bio-based polyimide (FPA-PI) films. The resulting films exhibited exceptional thermal stability, with 5% weight loss temperatures exceeding 425 °C and char yields ranging from 54% to 60%. Mechanical characterization revealed high elastic moduli (2.14–3.20 GPa), moderate tensile strengths (50–99 MPa), and favorable aging resistance. Gas permeation tests demonstrated promising CO₂/N₂ separation performance, with FPA-DODDA achieving superior CO₂/N₂ selectivity (27.721) compared to commercial films such as Matrimid^®, polysulfone, and polycarbonate, while FPA-BPFLDA exhibited enhanced CO₂ permeability (P(CO₂) = 2.526 Barrer), surpassing that of Torlon^®. The CO₂/N₂ separation performance of these FPA-PI films is governed synergistically by size-sieving effects and solution-diffusion mechanisms. This work not only introduces a novel synthetic route for bio-based polymers but also highlights the potential of replacing conventional petroleum-based materials with renewable alternatives in high-temperature and gas separation applications, thereby advancing environmental sustainability. Full article

The development of bio-based and biodegradable materials is critical for reducing environmental impact and addressing global challenges associated with the extensive use of plastics in packaging applications. In this study, linear oligomers of butylene succinate (OBS) with three different molecular weights were synthesized using succinic acid (SA) and 1,4-butanediol (BDO), both monomers derived from biomass. The synthesized fully bio-based OBS samples were characterized in terms of their molecular structure, degree of polymerization, crystallinity, and thermal properties, showcasing their potential as additives for biopolymers in food packaging. Oligomers with weight-average molecular weight (M_w) values of 2050 g·mol⁻¹ (OBS-L), 16,150 g·mol⁻¹ (OBS-M), and 33,147 g·mol⁻¹ (OBS-H), and Ð values in the 1.7–1.8 range were successfully synthesized. The results showed that the thermal degradation stability of OBS slightly increased, while the crystallinity decreased with increasing molecular weight. Furthermore, the analysis of the evolution of the lattice parameters suggested that oligomers with shorter chains favored crystal organization, resulting in a crystal unit cell with denser packing. Full article

Non-biodegradable superabsorbent polymers (SAPs) in personal care products (PCPs) pose significant environmental and health concerns despite their high absorption capacity. The aim of this study was to develop cellulose-based hydrogels as a sustainable alternative to those conventional SAPs, taking advantage of cellulose properties such as biocompatibility, biodegradability, and hydrophilicity. A synthesized allyl cellulose (AC) derivative was copolymerized with unusual monomers used in the production of SAPs, and the influence of monomer ratios, crosslinking density, and the ratio of cellulose to monomers on the absorption capacity was investigated and optimized. The most promising hydrogels were fully characterized for the proposed application and compared with a commercial SAP extracted from a baby diaper. The cellulose-based hydrogels showed promising absorption capacities in synthetic urine (~15 g/g), and a high centrifuge retention capacity (12.5 g/g), which was only slightly lower than the commercial SAP. These new hydrogels exhibited excellent biocompatibility and outperformed the established commercial diaper SAP. This study represents a more sustainable alternative to conventional SAPs, potentially reducing health risks while increasing the bio-based content of PCPs. Further optimization of these hydrogels could transform the hygiene product industry, by providing a balance between performance and environmental sustainability. Full article

This work demonstrates the fabrication of microstructures with formulations containing bio-based prepolymers derived from itaconic acid, commercial reactive diluents, photo initiators, and inhibitors, through two-photon polymerization. Lateral and vertical resolutions within the micron range can be achieved by the adjustment of laser scanning speed and pulse energy, and through the use of microscope objectives with high magnification and numerical aperture. The fabrication throughput can be slightly increased by simultaneously increasing the laser pulse energy and scanning speed, with special care to keep the resolution of the features that can be written via two-photon polymerization. Feasibility for the fabrication of 3D microstructures is demonstrated, through the fabrication of benchmark structures like woodpiles and pyramidal structures. Thus, this work proves that resins based on biobased formulations, originally designed for UV-curing 3D printing, can be adapted for two-photon polymerization, obtaining 3D microstructures with resolutions within the micron range. Full article

Conventional epoxy thermosets, with irreversible crosslinking networks, cannot be reprocessed and recycled. Furthermore, the utilization of petroleum-based materials accelerates the depletion of non-renewable resources. The introduction of dynamic covalent bonds and the use of bio-based materials for thermosets can effectively address the above issues. Herein, a series of bio-based epoxy vitrimers with dynamic covalent imine bonds were synthesized via a simple solvent-free, one-pot method using vanillin-derived aldehyde monomers, 4,4-diaminodiphenylsulfone (DDS) and bisphenol F diglycidyl ether (BFDGE) as raw materials. The effect of crosslinking density, crosslinking structure and imine bond content on the resulting bio-based vitrimers was studied, demonstrating their excellent thermal properties, UV shielding and solvent resistance, as well as outstanding mechanical properties compared to those of the previously reported vitrimers. In particular, the cured neat resin of vitrimer had a maximum tensile strength of 109 MPa and Young’s modulus of 6257 MPa, which are higher than those of previously reported imine-based vitrimers. The dynamic imine bonds endow these vitrimers with good reprocessability upon heating (over 70% recovery) and degradation under acidic conditions, enabling recycling by physical routes and gentle degradation by chemical routes. This study demonstrates a simple and effective process to prepare high-performance bio-based and recycled epoxy thermosets. Full article

A rapid microwave-assisted process minimizing waste was set up to produce bio-based benzoxazine-like monomers produced from vanillylamine and melamine. Without excessive purification, different viscous liquid precursors had a remarkable ability to form four strong and transparent different solid cross-linked thermosets, displaying lower curing temperatures under 130 °C. The long and strong adhesive performance of the cured materials was observed using glass slides or aluminum surfaces and they could become a good alternative to adhesive epoxy resin for metal surfaces. At the higher temperatures, these solids could act as efficient flame-retardants proven by thermogravimetric measurements. The best candidates gave a limiting oxidation index value of 41.9. In order to improve the intrinsic surface hydrophobicity of the phenolic resins, slight amounts of silica and iron oxide nanoparticles were dispersed in the polymer matrix, and finally mechanical resistance was pointed out. The most promising of our melamine-based resin was loaded with aluminum pigment to furnish a silver-colored paste ready for being cured to afford a robust solid, which does not undergo contraction or deformation. Full article

Rigid polyurethane foam (RPUF) is a widely utilized thermosetting polymer across various industrial applications, valued for its exceptional properties. However, the demand for sustainable alternatives to petroleum-based polymers has grown increasingly urgent due to rising environmental concerns. Despite its widespread use, RPUF faces challenges such as inadequate mechanical strength, limited thermal stability, and high flammability, all of which are crucial considerations in commercial and household applications. Globally, ongoing efforts are focused on developing innovative technologies that convert renewable sources into new monomers and polymers, some of which could serve as alternatives to traditional RPUFs. Several approaches have been explored to improve the thermal stability, mechanical strength, and flame retardancy of RPUFs, including the modification of bio-based polyols and the incorporation of performance-enhancing fillers. This review emphasizes recent advances in RPUFs derived from natural resources, focusing on their preparation, characterization, and properties, and strategies to enhance the mechanical strength and flame safety of bio-based RPUFs. Additionally, it explores the applications of RPUF materials across various fields, addressing the challenges and potential developments in packaging, household items, construction, and automotive applications. Full article

While the traditional rubber industry faces the severe pressure of environmental pollution and carbon emissions, bio-based and biodegradable elastomers have become a hot topic in the field and drawn intensive research interest. Inspired by polyester resin, incorporating polyol or polycarboxylic acid as a branching unit into aliphatic polyester and/or introducing a monomer with a C=C bond to provide open-bond cross-linking in the fashion of common vulcanization to form three-dimensional network structures are two mainstream strategies for designing biodegradable polyester elastomers (BPEs). Both methods encounter more or fewer problems, such as poor mechanical and thermal properties due to the easy hydrolysis of the ester bond and space hinderance, or the potential harm of the remaining degraded small molecules with olefin bonds. This article provides an overview of recent endeavors aimed at addressing these challenges and prospects the probable future advancements in the field. Full article

In the rapidly evolving biobased materials innovation landscape, our research identifies key players and explores the evolutionary perspective of biobased innovation, offering insights into promising research areas to be further developed by biobased material scientists in search of exploiting their knowledge in novel applications. Despite the crucial role of these materials in promoting sustainable production and consumption models, systematic studies on the current innovation terrain are lacking, leaving gaps in understanding key players, emerging technologies, and market trends. To address this void, we focused on examining patents related to biobased monomers and polymers, aiming to describe the innovation strategies and business dynamics of leading assignees. Embedded within the European Sustainable BIO-based nanoMAterials Community (BIOMAC) project, a Horizon 2020 initiative, our research leverages this unique framework dedicated to advancing the innovation landscape, specifically emphasizing the market readiness of biobased materials. We implemented a multi-stage strategy, prioritizing validated keyword queries to ensure the superior quality and reliability of the collected data. To understand primary contributors within these landscapes, we conducted an in-depth analysis of innovation strategies employed by leading companies. Findings from the ORBIT platform highlighted a remarkable increase in patent publications in the past decade, with China standing out as a key hub of innovation, signaling a strong focus on the development of these materials. Our research explores technological advancements in biobased materials to identify specific areas with potential for further development. By analyzing innovation trends in five key industries, we pinpoint opportunities for innovative solutions to be commercially exploited while ensuring compliance with intellectual property rights within a freedom-to-operate framework. Full article

This work describes the encapsulation of three different aliphatic isocyanates to reduce the risks associated with isocyanates’ direct handling. The use of bio-based polybutylene succinate (bio-PBS) increases the sustainability factor as it allows for the use of microcapsules (MCs) from renewable sources with biodegradable features. The three different MCs (MCs-Monomer, MCs-Trimer, and MCs-Polymer) are spherical, crack-free, and matrix-type, containing an isocyanate payload between 67 wt% and 70 wt%. Protection against environmental moisture was improved, resulting in losses of less than 10% for most cases after one month. The bio-PBS MCs were found to be suitable as crosslinking agents in high-performance adhesive formulations for the footwear industry. Adhesive joints with encapsulated isocyanate exhibited peel strength values ranging from 3.28 to 4.56 N/mm, well above the minimum requirements for the intended footwear application. Additionally, these joints demonstrated improved creep resistance compared to those using non-encapsulated isocyanates. In this context, the MCs-Trimer stood out, providing exceptional thermal robustness to the joints, as they showed no failure or opening at 90 °C, consistent with commercial adhesives. These results confirm that bio-PBS MCs can be excellent components for future adhesive formulations and that matrix-type MCs can also be utilised for this purpose. Full article