polymers-logo

Journal Browser

Journal Browser

Environmentally Friendly Bio-Based Polymeric Materials

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Circular and Green Polymer Science".

Deadline for manuscript submissions: closed (15 December 2023) | Viewed by 21649

Special Issue Editor


E-Mail Website
Guest Editor
Research Center for Environmental Protection and Eco-Friendly Technologies, Faculty of Chemical Engineering and Biotechnologies, National University of Science and Technology Politehnica of Bucharest, Bucharest, Romania
Interests: materials science; biomaterials and nanostructured materials; biophotonics; generation of the second harmonic (SHG); generation of the third harmonic (THG); biopolymers

Special Issue Information

Dear Colleagues,

This Special Issue is devoted to environmentally friendly polymeric materials. Review articles, original papers and short communications of preliminary, but significant, results are welcome.

The aim of this Special Issue is to encourage scientists to publish their experimental and theoretical results in as much detail as possible; there is no restriction on the length of the manuscripts. The full experimental details must be provided so that the results can be reproduced.

The main topics of this Special Issue are as follows:

  • Eco-friendly materials: related results and applications;
  • Polymers of biological origin: synthesis and characterization.

Interdisciplinary and/or multidisciplinary papers are welcome.

Dr. Ana-Maria Manea-Saghin
Guest Editor

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

  • bio-based polymers
  • eco-friendly materials
  • polymers
  • materials based on biopolymers
  • natural products
  • eco-nano-technologies
  • biocomposites
  • characterization techniques

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (13 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

18 pages, 2172 KiB  
Article
Effect of Pulping Waste Liquid on the Physicochemical Properties and the Prediction Model of Wheat Straw Residue Granular Fuels
by Lanxin Xue, Guihua Yang, Zhaoyun Lin, Jinze Li, Bo He and Jiachuan Chen
Polymers 2024, 16(6), 848; https://doi.org/10.3390/polym16060848 - 19 Mar 2024
Viewed by 892
Abstract
Herein, wheat straw residue and pulping waste liquid were collected from pulping mill and mixed to prepare bio-based granular fuels by using compression molding technology, and to explore the comprehensive utilization of the industrial waste of pulping and papermaking. The effects of pulping [...] Read more.
Herein, wheat straw residue and pulping waste liquid were collected from pulping mill and mixed to prepare bio-based granular fuels by using compression molding technology, and to explore the comprehensive utilization of the industrial waste of pulping and papermaking. The effects of pulping waste liquid on granular fuel properties were analyzed systemically. Further study of the function of pulping waste liquid, cellulose and hemicellulose was used to replace wheat straw residue and avoid the interference factors. Therefore, the prediction models of granular fuels were established with influencing factors that included cellulose, hemicellulose and pulping waste liquid. The granular fuels had the best performance with 18.30% solid content of pulping waste liquid. The highest transverse compressive strength of granular fuel was 102.61 MPa, and the activation energy was 81.71 KJ·mol−1. A series of curve fitting prediction models were established to clarify the forming process of granular fuel, and it turned out that the pulping waste liquid could improve the adhesion between solid particles and increase their compression resistance. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

12 pages, 1255 KiB  
Article
Effect of Starch Plasticization on Morphological, Mechanical, Crystalline, Thermal, and Optical Behavior of Poly(butylene adipate-co-terephthalate)/Thermoplastic Starch Composite Films
by Xiaoyan He, Fuhong Zhang, Congcong Li, Weiwei Ding, Yuanyuan Jin, Lisheng Tang and Ran Huang
Polymers 2024, 16(3), 326; https://doi.org/10.3390/polym16030326 - 25 Jan 2024
Cited by 1 | Viewed by 1736
Abstract
Starches plasticized with glycerol/citric acid/stearic acid and tributyl 2-acetylcitrate (ATBC), respectively, were processed with poly (butylene adipate-Co-terephthalate (PBAT) via extrusion and a film-blown process. All the composite films were determined for morphology, mechanical, thermal stability, crystalline, and optical properties. Results show that the [...] Read more.
Starches plasticized with glycerol/citric acid/stearic acid and tributyl 2-acetylcitrate (ATBC), respectively, were processed with poly (butylene adipate-Co-terephthalate (PBAT) via extrusion and a film-blown process. All the composite films were determined for morphology, mechanical, thermal stability, crystalline, and optical properties. Results show that the most improved morphology was in the 30% glycerol plasticized PBAT/thermoplastic starch (TPS) composite films, characterized by the smallest and narrowest distribution of TPS particle sizes and a more uniform dispersion of TPS particles. However, the water absorption of PBAT/TPS composite films plasticized with glycerol surpassed that observed with ATBC as a plasticizer. Mechanical properties indicated insufficient plasticization of the starch crystal structure when using 10% ATBC, 20% ATBC, and 20% glycerol as plasticizers, leading to poor compatibility between PBAT and TPS. This resulted in stress concentration points under external forces, adversely affecting the mechanical properties of the composites. All PBAT/TPS composite films exhibited a negative impact on the initial thermal decomposition temperature compared to PBAT. Additionally, the haze value of PBAT/TPS composite films exceeded 96%, while pure PBAT had a haze value of 47.42%. Films plasticized with 10% ATBC, 20% ATBC, and 20% glycerol displayed lower transmittance values in the visible light region. The increased transmittance of films plasticized with 30% glycerol further demonstrated their superior plasticizing effect compared to other PBAT/TPS composite films. This study provides a simple and feasible method for preparing low-cost PBAT composites, and their extensions are expected to further replace general-purpose plastics in daily applications. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

19 pages, 8209 KiB  
Article
Optical Limiting Properties of DNA Biopolymer Doped with Natural Dyes
by Petronela Gheorghe, Adrian Petris and Adina Mirela Anton
Polymers 2024, 16(1), 96; https://doi.org/10.3390/polym16010096 - 28 Dec 2023
Cited by 1 | Viewed by 1010
Abstract
The high-power lasers have important implications for present and future light-based technologies; therefore, the protection measures against their high-intensity radiation are extremely important. Currently, a great deal of interest is directed towards the development of new nonlinear optical materials for passive optical limiters, [...] Read more.
The high-power lasers have important implications for present and future light-based technologies; therefore, the protection measures against their high-intensity radiation are extremely important. Currently, a great deal of interest is directed towards the development of new nonlinear optical materials for passive optical limiters, which are used to protect the human eye and sensitive optical and optoelectronic devices from laser-induced damage. Biopolymers doped with natural dyes are emerging as a new class of optical materials with interesting photosensitive properties. In this paper, the optical limiting capability of deoxyribonucleic acid bio-polymer functionalized with Turmeric natural dye has been demonstrated for the first time, to the best of our knowledge. The experimental investigation of the optical limit has been done by the Intensity-scan method in the NIR spectral domain at the important telecommunication wavelength of 1550 nm, using ultrashort laser pulses (~120 fs). Several optical properties of this natural dye are presented and discussed. The values of the optical transmittance in the linear regime, the saturation intensity of the nonlinear transmittance curves, and the coefficient of the nonlinear absorption have been determined. The influence of the DNA biopolymer and natural dye concentration on the optical limiting properties of the investigated biomaterials is reported and discussed. The photostability and thermal stability of the investigated solutions have also been evaluated by monitoring the temporal decay of the normalized absorption spectra under illumination with UVA light and heating, respectively. Our results evidence the positive influence of the DNA, which embeds Turmeric natural dye, on the optical limiting functionality itself and on the photostability and thermal stability of this novel material. The performed study reveals the potential of the investigated novel biomaterial for applications in nonlinear photonics, in particular in optical limiting. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

18 pages, 3332 KiB  
Article
The Evolution of the Intrinsic Flexural Strength of Jute Strands after a Progressive Delignification Process and Their Contribution to the Flexural Strength of PLA-Based Biocomposites
by Francisco J. Alonso-Montemayor, Francesc X. Espinach, Quim Tarrés, Manel Alcalà, Marc Delgado-Aguilar and Pere Mutjé
Polymers 2024, 16(1), 37; https://doi.org/10.3390/polym16010037 - 21 Dec 2023
Cited by 2 | Viewed by 1013
Abstract
Biocomposites from poly-(lactic acid) (PLA) and jute strands were prepared, and their flexural strength was analyzed. Jute strands were submitted to a progressive delignification process and the resulting morphology, composition, and crystallinity index were evaluated. Then, PLA biocomposites comprising 30 wt% of jute [...] Read more.
Biocomposites from poly-(lactic acid) (PLA) and jute strands were prepared, and their flexural strength was analyzed. Jute strands were submitted to a progressive delignification process and the resulting morphology, composition, and crystallinity index were evaluated. Then, PLA biocomposites comprising 30 wt% of jute strands were produced and characterized under flexural conditions. The delignification processes decreased the lignin content and progressively increased the cellulose content. All this resulted in an enhancement of the composite flexural strength. A modified rule of mixtures, and the relation between tensile and flexural properties were used to determine the intrinsic flexural strength (of the jute strands) and their correlation with their physic-chemical characteristics. Equations correlating the intrinsic flexural strength with the crystallinity index, the cellulose content, and the microfibril angle were proposed. These equations show the impact of these properties over the intrinsic properties of the fibers and can help researchers to select appropriate fibers to obtain accurate properties for the composites. Jute strands show their value as reinforcement by increasing the flexural strength of the matrix by 70% and being less expensive and more environmentally friendly than mineral reinforcements. Together with the profitability and the environmental advantages, the mechanical results suggest that these PLA biocomposites are suitable for specific products of different market sectors. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

17 pages, 3282 KiB  
Article
Utilization of Torrefied and Non-Torrefied Short Rotation Willow in Wood–Plastic Composites
by Jaka Gašper Pečnik, Mariem Zouari, Matthew Schwarzkopf and David B. DeVallance
Polymers 2023, 15(19), 3997; https://doi.org/10.3390/polym15193997 - 5 Oct 2023
Cited by 2 | Viewed by 1027
Abstract
The torrefaction process is widely used in the energy field, but the characteristics of the torrefied wood also have positive effects on the production of wood plastic composites. In this study, short-rotation shrub willow was torrefied at 225 and 300 °C and incorporated [...] Read more.
The torrefaction process is widely used in the energy field, but the characteristics of the torrefied wood also have positive effects on the production of wood plastic composites. In this study, short-rotation shrub willow was torrefied at 225 and 300 °C and incorporated into polypropylene composites filled with changing levels of weight percent (wt%) of non-torrefied and torrefied (5, 15, 25, and 40 wt%) wood. Nine different formulations were extruded for mechanical, thermal, and water absorption properties. The tensile properties of composites were not affected by any level of torrefaction, while higher flexure properties were in favor of lower wt% of torrefied wood. The slowest rate of thermal degradation was confirmed for the highest wt% of torrefied wood with a torrefaction temperature of 300 °C. In contrast, the presence of torrefied wood in composites did not show a difference in crystallization or melting temperatures. The most noticeable contribution of torrefaction temperature and wt% was found for water-absorbing properties, where the higher torrefaction temperature and largest wt% of torrefied wood in the composite resulted in decreased water uptake. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

16 pages, 2399 KiB  
Article
Particle Shedding from Cotton and Cotton-Polyester Fabrics in the Dry State and in Washes
by Tanja Pušić, Branka Vojnović, Sandra Flinčec Grgac, Mirjana Čurlin and Rajna Malinar
Polymers 2023, 15(15), 3201; https://doi.org/10.3390/polym15153201 - 27 Jul 2023
Cited by 5 | Viewed by 1398
Abstract
The influence of 3, 10 and 50 washing cycles on the properties of cotton fabric and cotton-polyester blend in plain weave, was investigated in this study. In addition to the analysis of tensile properties in weft and warp directions and thickness, the number [...] Read more.
The influence of 3, 10 and 50 washing cycles on the properties of cotton fabric and cotton-polyester blend in plain weave, was investigated in this study. In addition to the analysis of tensile properties in weft and warp directions and thickness, the number of particles produced in the dry state was also measured after 3, 10 and 50 washes. After washing, the entire effluent was analysed by determining the total suspended solids (TSS), the total solids (TS), the pH value and the conductivity. To determine the similarity of the observed wash cycles and properties of all processed samples, hierarchical cluster analysis (HCA) was performed. The fabric changes indicated by total wear in the warp direction after 50 washing cycles compared to unwashed ones amounting to 41.2% for cotton and 30.9% for cotton-polyester blend, may be attributed to the synergy of washing factors and raw material composition. Cotton fabric produced significantly more particles than cotton-polyester fabric in the dry state after the examined washing cycles in all size categories. A smaller number of released particles are in the larger size category >25 μm. The obtained TSS values confirm the degree of loading of the effluent with particulate matter from the analysed fabrics, since the detergent consists of water-soluble components. The HCA dendrograms confirmed that the release of particles during the first washing cycles is mainly determined by the structural properties of fabrics, while in the subsequent cycles the synergistic effect of chemical, mechanical and thermal effects in the interaction with the material prevailed. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

18 pages, 3421 KiB  
Article
One-Step Method for Direct Acrylation of Vegetable Oils: A Biobased Material for 3D Printing
by Cristian Mendes-Felipe, Igor Isusi, Olga Gómez-Jiménez-Aberasturi, Soraya Prieto-Fernandez, Leire Ruiz-Rubio, Marco Sangermano and José Luis Vilas-Vilela
Polymers 2023, 15(14), 3136; https://doi.org/10.3390/polym15143136 - 24 Jul 2023
Cited by 10 | Viewed by 2145
Abstract
The substitution of fossil resources by alternatives derived from biomass is a reality that is taking on a growing relevance in the chemical and energy industries. In this sense, fats, oils, and their derived products have become indispensable inputs due to their broad [...] Read more.
The substitution of fossil resources by alternatives derived from biomass is a reality that is taking on a growing relevance in the chemical and energy industries. In this sense, fats, oils, and their derived products have become indispensable inputs due to their broad functional attributes, stable price and sustainable character. Acrylated vegetable oils are considered to be very versatile materials for very broad applications (such as in adhesives, coatings or inks) since, in the presence of photoinitiators, they can be polymerized by means of UV-initiated free radical polymerizations. The usual process for the synthesis of acrylate vegetable oils consists in reacting epoxidized oils derivatives with acrylic acid. Here, the influence of different catalysts on the activity and selectivity of the process of acrylation of epoxidized soybean oil is studied. In addition, a novel one-step method for direct acrylation of vegetable oils is also explored. This new approach advantageously uses the original vegetable resource and eliminates intermediate reactions, thus being more environmentally efficient. This study offers a simple and low-cost option for synthesizing a biomass-derived monomer and studies the potential for the 3D printing of complex structures via digital light processing (DLP) 3D printing of the thus-obtained novel sustainable formulations. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Graphical abstract

18 pages, 3092 KiB  
Article
Designing Sustainable Polymer Blends: Tailoring Mechanical Properties and Degradation Behaviour in PHB/PLA/PCL Blends in a Seawater Environment
by Leonardo G. Engler, Naiara C. Farias, Janaina S. Crespo, Noel M. Gately, Ian Major, Romina Pezzoli and Declan M. Devine
Polymers 2023, 15(13), 2874; https://doi.org/10.3390/polym15132874 - 29 Jun 2023
Cited by 8 | Viewed by 2528
Abstract
Biodegradable polyesters are a popular choice for both packaging and medical device manufacture owing to their ability to break down into harmless components once they have completed their function. However, commonly used polyesters such as poly(hydroxybutyrate) (PHB), poly(lactic acid) (PLA), and polycaprolactone (PCL), [...] Read more.
Biodegradable polyesters are a popular choice for both packaging and medical device manufacture owing to their ability to break down into harmless components once they have completed their function. However, commonly used polyesters such as poly(hydroxybutyrate) (PHB), poly(lactic acid) (PLA), and polycaprolactone (PCL), while readily available and have a relatively low price compared to other biodegradable polyesters, do not meet the degradation profiles required for many applications. As such, this study aimed to determine if the mechanical and degradation properties of biodegradable polymers could be tailored by blending different polymers. The seawater degradation mechanisms were evaluated, revealing surface erosion and bulk degradation in the blends. The extent of degradation was found to be dependent on the specific chemical composition of the polymer and the blend ratio, with degradation occurring via hydrolytic, enzymatic, oxidative, or physical pathways. PLA presents the highest tensile strength (67 MPa); the addition of PHB and PCL increased the flexibility of the samples; however, the tensile strength reduced to 25.5 and 18 MPa for the blends 30/50/20 and 50/25/25, respectively. Additionally, PCL presented weight loss of up to 10 wt.% and PHB of up to 6 wt.%; the seawater degradation in the blends occurs by bulk and surface erosion. The blending process facilitated the flexibility of the blends, enabling their use in diverse industrial applications such as medical devices and packaging. The proposed methodology produced biodegradable blends with tailored properties within a seawater environment. Additionally, further tests that fully track the biodegradation process should be put in place; incorporating compatibilizers might promote the miscibility of different polymers, improving their mechanical properties and biodegradability. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

18 pages, 6539 KiB  
Article
Ecofriendly Elimination of Ni (II) Using Fabricated Nanocomposite Based on Chitosan/Silver Nanoparticles/Carbon Nanotubes
by Eid M. S. Azzam, Walaa I. Elsofany, Fahad Abdulaziz, Hind A. AlGhamdi and Abdullah Y. AL alhareth
Polymers 2023, 15(13), 2759; https://doi.org/10.3390/polym15132759 - 21 Jun 2023
Cited by 2 | Viewed by 1080
Abstract
Nickel ions are hazardous heavy metals that are non-biodegradable and can lead to allergic sensitivity and dermatitis. Nanomaterials are chosen for their effective elimination of impurities from water structures based entirely on the variety of therapy and degree of purification. The target of [...] Read more.
Nickel ions are hazardous heavy metals that are non-biodegradable and can lead to allergic sensitivity and dermatitis. Nanomaterials are chosen for their effective elimination of impurities from water structures based entirely on the variety of therapy and degree of purification. The target of this work was the combination of the properties of biopolymers such as chitosan, silver nanoparticles (SNPs), and carbon nanotubes (CNTs) in one ecofriendly compound for Ni (II) uptake from the aqueous solution. To attain this target, the endeavor was made by creating a nanocomposite based on chitosan/SNPs/CNTs. The characterization of the structure of the fabricated nanocomposite (Chit-SNPs-CNTs) was carried out using different techniques. The removal of Ni (II) was examined by studying the adsorption of Ni (II) ions onto the fabricated nanocomposite by batch adsorption using UV, XRD, XPS, and ICP techniques. Moreover, we investigated the effect of the contact time, pH of the solution, and mass of the adsorbent on the efficiency of the adsorption of Ni (II). The results show that the adsorption capacity of Ni (II) increased by increasing the contact time with a neutral pH. The maximum removal of Ni (II) ions (99.70%) was found using 0.3 g of the (Chit-SNPs-CNTs) nanocomposite. In addition, the results indicate that the fabricated nanocomposite has a high adsorption effectivity, which is associated to the function of the chitosan, SNPs, and CNTs in upgrading the adsorption efficiency. Finally, the results in the existing work indicate that the ecofriendly nanocomposite organized here gave excessive effectivity closer to the elimination of Ni (II). Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

13 pages, 966 KiB  
Article
Innovative Collagen Based Biopolymers Tested as Fertilizers for Poor Soils Amendment
by Carolina Constantin, Daniela Simina Stefan, Ana-Maria Manea-Saghin and Irina Meghea
Polymers 2023, 15(9), 2085; https://doi.org/10.3390/polym15092085 - 27 Apr 2023
Cited by 1 | Viewed by 1479
Abstract
Improving soil quality is of growing interest and, among optimal solutions, the reuse and recycling of biopolymers of pelt waste from the tannery industry have been proposed, one of them being for collagen hydrolysate with micronutrients and polymers incorporated, to be used as [...] Read more.
Improving soil quality is of growing interest and, among optimal solutions, the reuse and recycling of biopolymers of pelt waste from the tannery industry have been proposed, one of them being for collagen hydrolysate with micronutrients and polymers incorporated, to be used as fertilizers for poor soils rehabilitation. As functionalization agents, polyacrylamide, starch and dolomite were included into biopolymer matrixes in order to enhance their specific efficiency. These fertilizers were adequately characterized for their physical–chemical properties, including nutrient content, and tested on three poor soils, while a fourth sample of normal soil was chosen for comparative purposes. These soils were also characterized for their texture and physical–chemical properties in order to establish the fertility state of the soils as a function of nutrient content. In this respect, a series of agrochemical tests were developed at laboratory scale, simulating real agriculture environments in a vegetation room, where a significant plant growth in height was observed for all the agro-hydrogels with nutrients encapsulated, and multiplication of the nodosities number was observed in the case of the soybean culture. The most significant effect was obtained in the case of the fertilizer functionalized with starch. Finally, the application dose of the organic fertilizers for specific culture plants was estimated, such as field cultures (cereals, corn), field vegetables, vineyards or fruit-growing plantations. These agro-collagen fertilizers are particularly recommended for amendment of field cereals and vegetables. The novelty of this study mainly consists of the recovery and recycling of the pelt waste as efficient fertilizers after their adequate functionalization with synthetic or natural biopolymers. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

16 pages, 2722 KiB  
Article
Neodymium Recovery from the Aqueous Phase Using a Residual Material from Saccharified Banana-Rachis/Polyethylene-Glycol
by Byron Lapo, Sandra Pavón, Martin Bertau, Hary Demey, Miguel Meneses and Ana María Sastre
Polymers 2023, 15(7), 1666; https://doi.org/10.3390/polym15071666 - 27 Mar 2023
Viewed by 1399
Abstract
Neodymium (Nd) is a key rare earth element (REE) needed for the future of incoming technologies including road transport and power generation. Hereby, a sustainable adsorbent material for recovering Nd from the aqueous phase using a residue from the saccharification process is presented. [...] Read more.
Neodymium (Nd) is a key rare earth element (REE) needed for the future of incoming technologies including road transport and power generation. Hereby, a sustainable adsorbent material for recovering Nd from the aqueous phase using a residue from the saccharification process is presented. Banana rachis (BR) was treated with cellulases and polyethylene glycol (PEG) to produce fermentable sugars prior to applying the final residue (BR–PEG) as an adsorbent material. BR–PEG was characterized by scanning electron microscopy (SEM), compositional analysis, pH of zero charge (pHpzc), Fourier transform infrared analysis (FTIR) and thermogravimetric analysis (TGA). A surface response experimental design was used for obtaining the optimized adsorption conditions in terms of the pH of the aqueous phase and the particle size. With the optimal conditions, equilibrium isotherms, kinetics and adsorption–desorption cycles were performed. The optimal pH and particle size were 4.5 and 209.19 μm, respectively. BR–PEG presented equilibrium kinetics after 20 min and maximum adsorption capacities of 44.11 mg/g. In terms of reusage, BR–PEG can be efficiently reused for five adsorption–desorption cycles. BR–PEG was demonstrated to be a low-cost bioresourced alternative for recovering Nd by adsorption. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

12 pages, 1755 KiB  
Article
Influence of Chitosan and Grape Seed Extract on Thermal and Mechanical Properties of PLA Blends
by Victoria Goetjes, Claudia L. von Boyneburgk, Hans-Peter Heim and Marilia M. Horn
Polymers 2023, 15(6), 1570; https://doi.org/10.3390/polym15061570 - 22 Mar 2023
Cited by 2 | Viewed by 1831
Abstract
Blends based on polylactic acid (PLA), chitosan, and grape seed extract (GE) were prepared by extrusion and injection molding. The effect of chitosan (5% and 15% on PLA basis) and natural extract (1% on PLA basis) incorporated into the PLA host matrix was [...] Read more.
Blends based on polylactic acid (PLA), chitosan, and grape seed extract (GE) were prepared by extrusion and injection molding. The effect of chitosan (5% and 15% on PLA basis) and natural extract (1% on PLA basis) incorporated into the PLA host matrix was explored regarding the thermal and mechanical properties. GE showed antioxidant activity, as determined by the DPPH assay method. Chitosan and GE affect the degree of crystallinity up to 30% as the polysaccharide acts as a nucleating agent, while the extract reduces the mobility of PLA chains. The decomposition temperature was mainly affected by adding chitosan, with a reduction of up to 25 °C. The color of the blends was specially modified after the incorporation of both components, obtaining high values of b* and L* after the addition of chitosan, while GE switched to high values of a*. The elongation at break (EB) exhibited that the polysaccharide is mainly responsible for its reduction of around 50%. Slight differences were accessed in tensile strength and Young’s modulus, which were not statistically significant. Blends showed increased irregularities in their surface appearance, as observed by SEM analysis, corresponding to the partial miscibility of both polymers. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

Review

Jump to: Research

32 pages, 2384 KiB  
Review
Silver Bionanocomposites as Active Food Packaging: Recent Advances & Future Trends Tackling the Food Waste Crisis
by Federico Trotta, Sidonio Da Silva, Alessio Massironi, Seyedeh Fatemeh Mirpoor, Stella Lignou, Sameer Khalil Ghawi and Dimitris Charalampopoulos
Polymers 2023, 15(21), 4243; https://doi.org/10.3390/polym15214243 - 27 Oct 2023
Cited by 10 | Viewed by 2568
Abstract
Food waste is a pressing global challenge leading to over $1 trillion lost annually and contributing up to 10% of global greenhouse gas emissions. Extensive study has been directed toward the use of active biodegradable packaging materials to improve food quality, minimize plastic [...] Read more.
Food waste is a pressing global challenge leading to over $1 trillion lost annually and contributing up to 10% of global greenhouse gas emissions. Extensive study has been directed toward the use of active biodegradable packaging materials to improve food quality, minimize plastic use, and encourage sustainable packaging technology development. However, this has been achieved with limited success, which can mainly be attributed to poor material properties and high production costs. In the recent literature, the integration of silver nanoparticles (AgNPs) has shown to improve the properties of biopolymer, prompting the development of bionanocomposites. Furthermore, the antibacterial properties of AgNPs against foodborne pathogens leads towards food shelf-life improvement and provides a route towards reducing food waste. However, few reviews have analyzed AgNPs holistically throughout a portfolio of biopolymers from an industrial perspective. Hence, this review critically analyses the antibacterial, barrier, mechanical, thermal, and water resistance properties of AgNP-based bionanocomposites. These advanced materials are also discussed in terms of food packaging applications and assessed in terms of their performance in enhancing food shelf-life. Finally, the current barriers towards the commercialization of AgNP bionanocomposites are critically discussed to provide an industrial action plan towards the development of sustainable packaging materials to reduce food waste. Full article
(This article belongs to the Special Issue Environmentally Friendly Bio-Based Polymeric Materials)
Show Figures

Figure 1

Back to TopTop