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Feature Papers in Biomacromolecules, Biobased and Biodegradable Polymers, 2nd Edition

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Biobased and Biodegradable Polymers".

Deadline for manuscript submissions: closed (31 March 2023) | Viewed by 24779

Special Issue Editors


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Guest Editor
Laboratory of Polymer Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, GR 54124 Thessaloniki, Greece
Interests: synthesis and characterization of polyesters; development of biobased polymers; biodegradable polymers; polymer composites and nanocomposites; synthesis and characterization of copolymers; polymer blends; recycling of polymers with various techniques; enzymatic hydrolysis studies; modification of natural polymers; polymer for wastewater treatment pollutant removal; polymers for tissue engineering and drug delivery applications; drug–polymer solid dispersions; drug targeting; drug nanoencapsulation and microencapsulation
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Guest Editor
Biopolymers Group, Centro de Investigación en Alimentación y Desarrollo, Hermosillo 83304, Mexico
Interests: polysaccharides and their derivatization; polyelectrolyte complexes; smart polymers; functional polymeric materials and nanomaterials for biomedical and biotechnological applications
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Global mass production of plastics started in the 1950s, with an estimated total number of 8.3 to 9.1 million metric tons (Mt) already manufactured up to now. Around only 9% of these have been recycled and 12% incinerated, whereas the remaining 79% has now been accumulated in landfills or the natural environment, causing serious environmental issues. The worldwide demand for sustainability and green economy leads to significant research interest in the field of polymer technology in three different directions:

  • To replace the use of fossil-derived polymers in various applications with neat biomacromolecules or their derivatives;
  • To employ green synthesis processes in order to recover and/or synthesize monomers derived from renewable resources (biobased monomers);
  • To produce new eco-friendly, biodegradable polymers based on these monomers in a short time. 
  • This Special Issue of the international open access journal Polymers aims to collect cutting-edge, state-of-the-art, original full-length research articles and critical or tutorial reviews on the topic of ‘Biomacromolecules and Biobased and Biodegradable Polymers’, including but not limited to:
  • Properties of biomacromolecules and their applications in several fields;
  • Synthesis and characterization of macromolecules derivatives with the desired properties;
  • Eco-friendly processes to recover biobased monomers from biomass;
  • Biomass treatment to produce monomers appropriate for polymer synthesis;
  • Synthesis, properties, and applications of biobased and biodegradable polymers and copolymers;
  • Development of biocomposites and nanocomposites;
  • Biodegradable blends;
  • Biobased polymer recycling methods and depolymerization techniques;  
  • Advantages of biomacromolecules and/or biobased and biodegradable polymers.

Prof. Dr. Dimitrios Bikiaris
Dr. Waldo M. Argüelles-Monal
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Polymers is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • biomass
  • biobased monomers
  • eco-friendly polymers
  • biomacromolecules
  • biobased polymers
  • biodegradable polymers
  • polymer applications

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Published Papers (10 papers)

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Research

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12 pages, 6150 KiB  
Article
Tailoring Photoprotection of Polylactide with New Isobornyl Derivatives of Phenol and Aniline
by Vladimir A. Belyi, Ivan M. Kuzivanov, Irina V. Fedorova, Olga A. Shumova, Evgeniy M. Tropnikov, Elena I. Istomina, Irina Yu. Chukicheva and Aleksandr V. Kuchin
Polymers 2023, 15(9), 2141; https://doi.org/10.3390/polym15092141 - 29 Apr 2023
Cited by 4 | Viewed by 1418
Abstract
This article is devoted to the development of new photostabilizers for polylactide (PLA), a polymer that is an environmentally friendly alternative to polymers and is based on fossil raw materials. We have elucidated the role of the reaction center of two potential PLA [...] Read more.
This article is devoted to the development of new photostabilizers for polylactide (PLA), a polymer that is an environmentally friendly alternative to polymers and is based on fossil raw materials. We have elucidated the role of the reaction center of two potential PLA photoprotectors: N-isobornylaniline and 2-isobornylphenol, in reactions occurring in a polymer matrix under the action of UV-C radiation. PLA samples with the photostabilizers were irradiated under a wavelength of 253.7 nm for 4, 8 and 12 h. The effectiveness of the photostabilizers was evaluated based on FTIR spectrometric data, 1H and 13C NMR, scanning electron microscopy and simultaneous thermal analysis (TG-DSC). Both stabilizers led to the protection of ester bonds between monomer units of PLA. However, 2-isobornylphenol proved to be more effective at a concentration of 0.05 wt.%, while the optimal concentration of N-isobornylaniline was 0.5 wt.% by weight. TG-DSC showed that the addition of N-isobornylaniline led to an increase in PLA resistance to thermal decomposition; the temperature of the onset of weight loss increased by 2.8 °C at 0.05 wt.% and by 8.1 °C at 0.5 wt.% of N-isobornylaniline. The photoprotector 2-isobornylphenol, on the contrary, reduced the thermal stability of PLA. Full article
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14 pages, 2428 KiB  
Article
Thermal and Viscoelastic Responses of Selected Lignocellulosic Wastes: Similarities and Differences
by Daniela Ionita, Mariana Cristea, Susana Felicia Cosmulescu, Georgeta Predeanu, Valeria Harabagiu and Petrisor Samoila
Polymers 2023, 15(9), 2100; https://doi.org/10.3390/polym15092100 - 28 Apr 2023
Cited by 1 | Viewed by 1457
Abstract
Woody lignocellulosic biomasses comprise the non-edible parts of fruit trees. In recent years, the exploitation of this biomass has been widening in order to mitigate environmental issues. At the same time, this waste could be transformed into a value-added product (active carbon by [...] Read more.
Woody lignocellulosic biomasses comprise the non-edible parts of fruit trees. In recent years, the exploitation of this biomass has been widening in order to mitigate environmental issues. At the same time, this waste could be transformed into a value-added product (active carbon by pyrolysis, isolation of nanocellulose, oils or proteins). For either valorization path, a complete thermo-mechanical characterization is required. A detailed thermo-mechanical study (TGA, DSC, DMA) was performed on two types of lignocellulosic wastes, with and without kernels: on one side, the walnut shells (WS) and the pistachio shells (PsS) and, in the second category, the apricot seeds (AS), the date seeds (DS), and the plum seeds (PS). The results of the sample-controlled thermal analyses (HiRes TGA) evidenced a better resolution of the degradation steps of WS. Kinetic studies conducted also by conventional TGA (Flynn–Wall–Ozawa) and modulated TGA (MTGA) allowed us to make comparative reasonings concerning the degradation of the investigated biomasses. The DMA results revealed the effect of water traces and oil kernels on relaxation and supported the atypical DSC endotherm emphasized in the freezing temperature domain. Full article
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15 pages, 6579 KiB  
Article
Electrospun Cyclodextrin/Poly(L-lactic acid) Nanofibers for Efficient Air Filter: Their PM and VOC Removal Efficiency and Triboelectric Outputs
by Sompit Wanwong, Weradesh Sangkhun and Pimsumon Jiamboonsri
Polymers 2023, 15(3), 722; https://doi.org/10.3390/polym15030722 - 31 Jan 2023
Cited by 10 | Viewed by 2428
Abstract
In this work, PLLA and CD/PLLA nanofibers were fabricated using electrospinning and utilized as a particulate matter (PM) and volatile organic compounds (VOCs) filter. The electrospun PLLA and CD/PLLA were characterized with various techniques, including SEM, BET, FTIR, XRD, XPS, WCA, DSC, tensile [...] Read more.
In this work, PLLA and CD/PLLA nanofibers were fabricated using electrospinning and utilized as a particulate matter (PM) and volatile organic compounds (VOCs) filter. The electrospun PLLA and CD/PLLA were characterized with various techniques, including SEM, BET, FTIR, XRD, XPS, WCA, DSC, tensile strength testing, PM and VOCs removal efficiency, and triboelectric performance. The results demonstrated that the best air filter was 2.5 wt%CD/PLLA, which performed the highest filtration efficiencies of 96.84 ± 1.51% and 99.38 ± 0.43% for capturing PM2.5 and PM10, respectively. Its PM2.5 removal efficiency was 16% higher than that of pure PLLA, which were contributed by their higher surface area and porosity. These 2.5 wt%CD/PLLA nanofibers also exhibited the highest and the fastest VOC entrapment. For triboelectric outputs, the 2.5 wt%CD/PLLA-based triboelectric nanogenerator provided the highest electrical outputs as 245 V and 84.70 μA. These give rise to a three-fold enhancement of electrical outputs. These results indicated that the 2.5 wt%CD/PLLA can improve surface charge density that could capture more PM via electrostatic interaction under surrounding vibration. Therefore, this study suggested that 2.5 wt%CD/PLLA is a good candidate for a multifunction nanofibrous air filter that offers efficient PM and VOC removal. Full article
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13 pages, 2325 KiB  
Article
Synthesis, Thermal and Mechanical Properties of Fully Biobased Poly (hexamethylene succinate-co-2,5-furandicarboxylate) Copolyesters
by Chengqian Wang, Mingkun Chen, Zhiguo Jiang and Zhaobin Qiu
Polymers 2023, 15(2), 427; https://doi.org/10.3390/polym15020427 - 13 Jan 2023
Viewed by 1772
Abstract
Poly (hexamethylene succinate) (PHS) is a biobased and biodegradable polyester. In this research, two fully biobased high-molecular-weight poly (hexamethylene succinate-co-2,5-furandicarboxylate) (PHSF) copolyesters with low hexamethylene furandicarboxylate (HF) unit contents (about 5 and 10 mol%) were successfully synthesized through a two-step transesterification/esterification [...] Read more.
Poly (hexamethylene succinate) (PHS) is a biobased and biodegradable polyester. In this research, two fully biobased high-molecular-weight poly (hexamethylene succinate-co-2,5-furandicarboxylate) (PHSF) copolyesters with low hexamethylene furandicarboxylate (HF) unit contents (about 5 and 10 mol%) were successfully synthesized through a two-step transesterification/esterification and polycondensation method. The basic thermal behavior, crystal structure, isothermal crystallization kinetics, melting behavior, thermal stability, and tensile mechanical property of PHSF copolyesters were studied in detail and compared with those of PHS. PHSF showed a decrease in the melt crystallization temperature, melting temperature, and equilibrium melting temperature while showing a slight increase in the glass transition temperature and thermal decomposition temperature. PHSF copolyesters displayed the same crystal structure as PHS. Compared with PHS, PHSF copolyesters showed the improved mechanical property. The presence of about 10 mol% of HF unit increased the tensile strength from 12.9 ± 0.9 MPa for PHS to 39.2 ± 0.8 MPa; meanwhile, the elongation at break also increased from 498.5 ± 4.78% to 1757.6 ± 6.1%. Full article
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12 pages, 2413 KiB  
Article
Wood Flour Modified by Poly(furfuryl alcohol) as a Filler in Rigid Polyurethane Foams: Effect on Water Uptake
by Andrey Acosta, Arthur B. Aramburu, Rafael Beltrame, Darci A. Gatto, Sandro Amico, Jalel Labidi and Rafael de Avila Delucis
Polymers 2022, 14(24), 5510; https://doi.org/10.3390/polym14245510 - 16 Dec 2022
Cited by 5 | Viewed by 1851
Abstract
The use of lignocellulosic fillers in rigid polyurethane foams (RPUFs) has been receiving great attention due to their good mechanical and insulation properties and the high sustainable appeal of the obtained cellular polymers, although high water uptakes are found in most of these [...] Read more.
The use of lignocellulosic fillers in rigid polyurethane foams (RPUFs) has been receiving great attention due to their good mechanical and insulation properties and the high sustainable appeal of the obtained cellular polymers, although high water uptakes are found in most of these systems. To mitigate this detrimental effect, RPUFs filled with wood flour (2.5% wt) were fabricated with the addition of furfuryl alcohol (FA) to create a polymer grafted with the wood filler. Two concentrations of FA (10 wt% and 15 wt%) were investigated in relation to the wood flour, and the RPUFs were characterized for cell morphology, density, compressive properties, thermal stability, and water uptake. The introduction of wood flour as a filler decreased the cell size and increased the anisotropy index of the RPUFs and, in addition to that, the FA grafting increased these effects even more. In general, there were no significant changes in both mechanical and thermal properties ascribed to the incorporation of the fillers. On the other hand, a reduction of up to 200% in water uptake was ascribed to the FA-treated fillers. Full article
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15 pages, 3401 KiB  
Article
Impact of In Vitro Degradation on the Properties of Samples Produced by Additive Production from PLA/PHB-Based Material and Ceramics
by Alena Findrik Balogová, Marianna Trebuňová, Darina Bačenková, Miroslav Kohan, Radovan Hudák, Teodor Tóth, Marek Schnitzer and Jozef Živčák
Polymers 2022, 14(24), 5441; https://doi.org/10.3390/polym14245441 - 12 Dec 2022
Cited by 3 | Viewed by 1893
Abstract
The present study deals with preparing a polymer-based material with incorporated ceramics and monitoring changes in properties after in vitro natural degradation. The developed material is a mixture of polymers of polylactic acid and polyhydroxybutyrate in a ratio of 85:15. Ceramic was incorporated [...] Read more.
The present study deals with preparing a polymer-based material with incorporated ceramics and monitoring changes in properties after in vitro natural degradation. The developed material is a mixture of polymers of polylactic acid and polyhydroxybutyrate in a ratio of 85:15. Ceramic was incorporated into the prepared material, namely 10% hydroxyapatite and 10% tricalcium phosphate of the total volume. The material was processed into a filament form, and types of solid and porous samples were prepared using additive technology. These samples were immersed in three different solutions: physiological solution, phosphate-buffered saline, and Hanks’ solution. Under constant laboratory conditions, changes in solution pH, material absorption, weight loss, changes in mechanical properties, and surface morphology were monitored for 170 days. The average value of the absorption of the solid sample was 7.07%, and the absorption of the porous samples was recorded at 8.33%, which means a difference of 1.26%. The least change in pH from the reference value of 7.4 was noted with the phosphate-buffered saline solution. Computed tomography was used to determine the cross-section of the samples. The obtained data were used to calculate the mechanical properties of materials after degradation. The elasticity modulus for both the full and porous samples degraded in Hanks’ solution (524.53 ± 13.4 MPa) has the smallest deviation from the non-degraded reference sample (536.21 ± 22.69 MPa). Full article
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20 pages, 3635 KiB  
Article
Biopolymer-Based Films Reinforced with Green Synthesized Zinc Oxide Nanoparticles
by Johar Amin Ahmed Abdullah, Mercedes Jiménez-Rosado, Antonio Guerrero and Alberto Romero
Polymers 2022, 14(23), 5202; https://doi.org/10.3390/polym14235202 - 29 Nov 2022
Cited by 20 | Viewed by 2726
Abstract
Nowadays, biopolymer-based films are being developed as an alternative to conventional plastic-based films, mainly because they are non-toxic, flexible, inexpensive, and widely available. However, they are restricted in their applications due to several deficiencies in their properties. Accordingly, the reinforcement of these materials [...] Read more.
Nowadays, biopolymer-based films are being developed as an alternative to conventional plastic-based films, mainly because they are non-toxic, flexible, inexpensive, and widely available. However, they are restricted in their applications due to several deficiencies in their properties. Accordingly, the reinforcement of these materials with nanoparticles/nanofillers could overcome some of their shortcomings, especially those processed by green methods. Green synthesized zinc oxide nanoparticles (ZnO-NPs) are highly suggested to overcome these deficiencies. Therefore, the main aim of this work was to develop different biopolymer-based films from cellulose acetate (CA), chitosan (CH), and gelatin (GE) reinforced with ZnO-NPs prepared by casting, and to assess their different properties. The results show the improvements produced by the incorporation of ZnO-NPs (1% w/w) into the CA, CH, and GE systems. Thus, the water contact angles (WCAs) increased by about 12, 13, and 14%, while the water vapor permeability (WVP) decreased by about 14, 6, and 29%, the water solubility (WS) decreased by about 23, 6, and 5%, and the transparency (T) increased by about 19, 31, and 20% in the CA, CH, and GE systems, respectively. Furthermore, the mechanical properties were enhanced by increasing the ultimate tensile strength (UTS) (by about 39, 13, and 26%, respectively) and Young’s modulus (E) (by about 70, 34, and 63%, respectively), thereby decreasing the elongation at the break (εmax) (by about 56, 23, and 49%, respectively) and the toughness (by about 50, 4, and 30%, respectively). Lastly, the antioxidant properties were enhanced by 34, 49, and 39%, respectively. Full article
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27 pages, 7667 KiB  
Article
Tailoring and Long-Term Preservation of the Properties of PLA Composites with “Green” Plasticizers
by Marius Murariu, Yoann Paint, Oltea Murariu, Fouad Laoutid and Philippe Dubois
Polymers 2022, 14(22), 4836; https://doi.org/10.3390/polym14224836 - 10 Nov 2022
Cited by 17 | Viewed by 2769
Abstract
Concerning new polylactide (PLA) applications, the study investigates the toughening of PLA–CaSO4 β-anhydrite II (AII) composites with bio-sourced tributyl citrate (TBC). The effects of 5–20 wt.% TBC were evaluated in terms of morphology, mechanical and thermal properties, focusing on the enhancement of [...] Read more.
Concerning new polylactide (PLA) applications, the study investigates the toughening of PLA–CaSO4 β-anhydrite II (AII) composites with bio-sourced tributyl citrate (TBC). The effects of 5–20 wt.% TBC were evaluated in terms of morphology, mechanical and thermal properties, focusing on the enhancement of PLA crystallization and modification of glass transition temperature (Tg). Due to the strong plasticizing effects of TBC (even at 10%), the plasticized composites are characterized by significant decrease of Tg and rigidity, increase of ductility and impact resistance. Correlated with the amounts of plasticizer, a dramatic drop in melt viscosity is also revealed. Therefore, for applications requiring increased viscosity and enhanced melt strength (extrusion, thermoforming), the reactive modification, with up to 1% epoxy functional styrene–acrylic oligomers, was explored to enhance their rheology. Moreover, larger quantities of products were obtained by reactive extrusion (REX) and characterized to evidence their lower stiffness, enhanced ductility, and toughness. In current prospects, selected samples were tested for the extrusion of tubes (straws) and films. The migration of plasticizer was not noted (at 10% TBC), whereas the mechanical and thermal characterizations of films after two years of aging evidenced a surprising preservation of properties. Full article
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20 pages, 5653 KiB  
Article
The 3D Printability and Mechanical Properties of Polyhydroxybutyrate (PHB) as Additives in Urethane Dimethacrylate (UDMA) Blends Polymer for Medical Application
by Ahmad Adnan Abu Bakar, Muhammad Zulhilmi Zainuddin, Shahino Mah Abdullah, Nizam Tamchek, Ikhwan Syafiq Mohd Noor, Muhammad Syafiq Alauddin, Ahmad Alforidi and Mohd Ifwat Mohd Ghazali
Polymers 2022, 14(21), 4518; https://doi.org/10.3390/polym14214518 - 25 Oct 2022
Cited by 10 | Viewed by 2918
Abstract
The integration of additive manufacturing (3D printing) in the biomedical sector required material to portray a holistic characteristic in terms of printability, biocompatibility, degradability, and mechanical properties. This research aims to evaluate the 3D printability and mechanical properties of polyhydroxybutyrate (PHB) as additives [...] Read more.
The integration of additive manufacturing (3D printing) in the biomedical sector required material to portray a holistic characteristic in terms of printability, biocompatibility, degradability, and mechanical properties. This research aims to evaluate the 3D printability and mechanical properties of polyhydroxybutyrate (PHB) as additives in the urethane dimethacrylate (UDMA) based resin and its potential for medical applications. The printability of the PHB/UDMA resin blends was limited to 11 wt.% as it reached the maximum viscosity value at 2188 cP. Two-way analysis of variance (ANOVA) was also conducted to assess the significant effect of the varied PHB (wt.%) incorporation within UDMA resin, and the aging duration of 3D printed PHB/UDMA on mechanical properties in terms of tensile and impact properties. Meanwhile, the increasing crystallinity index (CI) of X-ray diffraction (XRD) in the 3D printed PHB/UDMA as the PHB loading increased, indicating that there is a strong correlation with the lower tensile and impact strength. FESEM images also proved that the agglomerations that occurred within the UDMA matrix had affected the mechanical performance of 3D printed PHB/UDMA. Nonetheless, the thermal stability of the 3D printed PHB/UDMA had only a slight deviation from the 3D printed UDMA since it had better thermal processability. Full article
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Review

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22 pages, 2360 KiB  
Review
Sustainable Development Approaches through Wooden Adhesive Joints Design
by Catarina S. P. Borges, Shahin Jalali, Panayiotis Tsokanas, Eduardo A. S. Marques, Ricardo J. C. Carbas and Lucas F. M. da Silva
Polymers 2023, 15(1), 89; https://doi.org/10.3390/polym15010089 - 26 Dec 2022
Cited by 7 | Viewed by 4578
Abstract
Over recent decades, the need to comply with environmental standards has become a concern in many industrial sectors. As a result, manufacturers have increased their use of eco-friendly, recycled, recyclable, and, overall, more sustainable materials and industrial techniques. One technique highly dependent on [...] Read more.
Over recent decades, the need to comply with environmental standards has become a concern in many industrial sectors. As a result, manufacturers have increased their use of eco-friendly, recycled, recyclable, and, overall, more sustainable materials and industrial techniques. One technique highly dependent on petroleum-based products, and at the edge of a paradigm change, is adhesive bonding. Adhesive bonding is often used to join composite materials and depends upon an adhesive to achieve the connection. However, the matrices of the composite materials and the adhesives used, as well as, in some cases, the composite fibres, are manufactured from petrochemical products. Efforts to use natural composites and adhesives are therefore ongoing. One composite that has proven to be promising is wood due to its high strength and stiffness (particularly when it is densified), formability, and durability. However, wood must be very carefully characterised since its properties can be variable, depending on the slope of the grains, irregularities (such as knots, shakes, or splits), and on the location and climate of each individual tree. Therefore, in addition to neat wood, wood composites may also be a promising option to increase sustainability, with more predictable properties. To bond wood or wooden composite substrates, bio-adhesives can be considered. These adhesives are now formulated with increasingly enhanced mechanical properties and are becoming promising alternatives at the structural application level. In this paper, wooden adhesive joints are surveyed considering bio-adhesives and wood-based substrates, taking into consideration the recent approaches to improve these base materials, accurately characterise them, and implement them in adhesive joints. Full article
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