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Development of Bio-Based Materials: Synthesis, Characterization and Applications

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

Deadline for manuscript submissions: closed (25 June 2022) | Viewed by 119724

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Guest Editor
Departamento de Ingeniería Química, Chemical Process and Product Technology Research Centre (Pro2TecS), Universidad de Huelva, Huelva, Spain
Interests: supercapacitors; energy storage; hypercrosslinked polymers; adsorption; biomaterials
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Departamento de Ingeniería Química, Chemical Process and Product Technology Research Centre (Pro2TecS), Universidad de Huelva, Huelva, Spain
Interests: rheology; lubricating greases; colloids; biopolymers; gels; adhesives; bio-based materials; vegetable oils; emulsions
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Departamento de Ingeniería Química, Chemical Process and Product Technology Research Centre (Pro2TecS), Universidad de Huelva, Huelva, Spain
Interests: lignocellulose; cellulose pulp; epoxidized biopolymers; bio-based materials; biolubricating grease; rheology
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Departamento de Ingeniería Química, Chemical Process and Product Technology Research Centre (Pro2TecS), Universidad de Huelva, Huelva, Spain
Interests: lignocellulosic materials; biomaterials; biopolymers; polyurethane; adhesives; rheology; vegetable oil
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Departamento de Ingeniería Química, Chemical Process and Product Technology Research Centre (Pro2TecS), Universidad de Huelva, Huelva, Spain
Interests: tannin-based materials; rigid foams; porous material characterization; non-aqueous emulsions; stability; phase change materials (PCM); rheology
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The present Special Issue deals with the need to find suitable biomaterials and procedures from which alternative products, able to imitate or even enhance the performance of currently used products, can be obtained. Thus, the development of partial or fully bio-based materials is greatly welcome. Furthermore, the search for alternative procedures that can reduce the carbon footprint or optimize both production and energy consumption is also encouraged. Special emphasis can be put into the synthesis, characterization, or/and application.

Dr. Antonio M Borrero-López
Prof. Dr. Concepción Valencia Barragán
Dr. Esperanza Cortés Triviño
Dr. Adrián Tenorio-Alfonso
Dr. Clara Delgado-Sánchez
Guest Editors

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Keywords

  • biomaterials
  • bioproduct
  • biopolymers
  • lignocellulose
  • vegetable oil
  • lignin
  • cellulose
  • hemicellulose
  • chitin
  • chitosan
  • ecofriendly procedure
  • optimization
  • biomass
  • proteins
  • polysaccharides
  • polyphenols
  • bio-sourced products
  • natural resources
  • environmentally-friendly products
  • biodegradation
  • colloids
  • emulsions

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Published Papers (30 papers)

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Editorial

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4 pages, 734 KiB  
Editorial
Development of Bio-Based Materials: Synthesis, Characterization and Applications
by Clara Delgado-Sánchez, Adrián Tenorio-Alfonso, Esperanza Cortés-Triviño, Antonio M. Borrero-López and Concepción Valencia
Polymers 2022, 14(17), 3599; https://doi.org/10.3390/polym14173599 - 31 Aug 2022
Cited by 1 | Viewed by 1836
Abstract
The need to find suitable biomaterials and procedures from alternative products able to imitate or even enhance the performance of currently used products has become an important focus of research today due to the depletion of non-renewable resources and the increasing concern related [...] Read more.
The need to find suitable biomaterials and procedures from alternative products able to imitate or even enhance the performance of currently used products has become an important focus of research today due to the depletion of non-renewable resources and the increasing concern related to climate change, sustainability and environmental preservation [...] Full article
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Research

Jump to: Editorial, Review

17 pages, 4637 KiB  
Article
Fe(III)-Rhamnoxylan—A Novel High Spin Fe(III) Octahedral Complex Having Versatile Physical and Biological Properties
by Anum Hayat, Mohammad Saeed Iqbal, Naveed Ahmad, Nabil K. Alruwaili and Atta ur Rehman
Polymers 2022, 14(20), 4290; https://doi.org/10.3390/polym14204290 - 12 Oct 2022
Cited by 1 | Viewed by 1680
Abstract
An iron (III) complex with rhamnoxylan, a hemicellulose from Salvia plebeia seeds, was synthesized and characterized by elemental analysis, spectroscopic and magnetic susceptibility measurements, thermal analysis and scanning electron microscopy. The rhamnoxylan was found to be a branched hemicellulose consisting of β-1,4-linked xylose [...] Read more.
An iron (III) complex with rhamnoxylan, a hemicellulose from Salvia plebeia seeds, was synthesized and characterized by elemental analysis, spectroscopic and magnetic susceptibility measurements, thermal analysis and scanning electron microscopy. The rhamnoxylan was found to be a branched hemicellulose consisting of β-1,4-linked xylose main chain and rhamnose attached to the chain at β-1,3 positions. The complex was found to contain 18.8% w/w iron. A high-spin octahedral geometry of Fe3+ was indicated by the electronic absorption spectrum of the complex. In other experiments, the complex exhibited good electrical and magnetic properties. In vivo efficacy, as hematinic, of the complex in induced anemia was demonstrated equivalent to that of iron protein succinylate (taken as standard) as evidenced by raised red blood cell count, hemoglobin, hematocrit and total iron in rabbit. The complex was found to be non-toxic with LD50 > 5000 mg kg−1 body weight in rabbit. Thus, iron(III)-rhamnoxylan hold the potential for application as hematinic for treatment of iron deficiency anemia. Full article
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13 pages, 3432 KiB  
Article
Effect of Bleaching and Hot-Pressing Conditions on Mechanical Properties of Compressed Wood
by Le Van Hai, Duc Hoa Pham and Jaehwan Kim
Polymers 2022, 14(14), 2901; https://doi.org/10.3390/polym14142901 - 17 Jul 2022
Cited by 7 | Viewed by 1769
Abstract
This paper reports on multiple stage bleaching and its effect on the mechanical and swelling properties of compressed wood (CW). The natural wood specimen was bleached with NaClO2 in five steps and three hot-pressing conditions. Their effects were investigated in morphologies: lignin [...] Read more.
This paper reports on multiple stage bleaching and its effect on the mechanical and swelling properties of compressed wood (CW). The natural wood specimen was bleached with NaClO2 in five steps and three hot-pressing conditions. Their effects were investigated in morphologies: lignin content, alpha-cellulose content, compression ratio, mechanical properties, swelling and, water contact angle. After compression, the wood specimens became dense and the most porous structures collapsed. The lignin content decreased as the bleaching steps progressed, and the highest alpha-cellulose content was observed at the third bleaching step. This CW showed the best mechanical properties: bending strength was 240.1 ± 35.7 MPa, and Young’s modulus was 23.08 ± 0.89 Gpa. The CW swelling decreased as the bleaching step progressed, and was associated with the density decrease and the compression ratio increase with the bleaching step. The B3 is an optimum bleaching step that accounts for the best mechanical properties, which might be associated with the highest alpha-cellulose content. Full article
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17 pages, 3365 KiB  
Article
Thermo-Responsive Shape Memory Vanillin-Based Photopolymers for Microtransfer Molding
by Justinas Jaras, Aukse Navaruckiene, Edvinas Skliutas, Jurga Jersovaite, Mangirdas Malinauskas and Jolita Ostrauskaite
Polymers 2022, 14(12), 2460; https://doi.org/10.3390/polym14122460 - 16 Jun 2022
Cited by 6 | Viewed by 2606
Abstract
Novel thermo-responsive shape-memory vanillin-based photopolymers have been developed for microtransfer molding. Different mixtures of vanillin dimethacrylate with tridecyl methacrylate and 1,3-benzenedithiol have been tested as photocurable resins. The combination of the different reaction mechanisms, thiol-acrylate photopolymerization, and acrylate homopolymerization, that were tuned by [...] Read more.
Novel thermo-responsive shape-memory vanillin-based photopolymers have been developed for microtransfer molding. Different mixtures of vanillin dimethacrylate with tridecyl methacrylate and 1,3-benzenedithiol have been tested as photocurable resins. The combination of the different reaction mechanisms, thiol-acrylate photopolymerization, and acrylate homopolymerization, that were tuned by changing the ratio of monomers, resulted in a wide range of the thermal and mechanical properties of the photopolymers obtained. All polymers demonstrated great shape-memory properties and were able to return to their primary shape after the temperature programming and maintain their temporary shape. The selected compositions weretested by the microtransfer molding technique and showed promising results. The developed thermo-responsive shape-memory bio-based photopolymers have great potential for forming microtransfered structures and devices applicable on non-flat surfaces. Full article
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10 pages, 3466 KiB  
Article
Relation between Droplet Size Distributions and Physical Stability for Zein Microfluidized Emulsions
by Jenifer Santos, Luis Alfonso Trujillo-Cayado, Francisco Carrillo, María Luisa López-Castejón and María Carmen Alfaro-Rodríguez
Polymers 2022, 14(11), 2195; https://doi.org/10.3390/polym14112195 - 28 May 2022
Cited by 13 | Viewed by 2726
Abstract
Zein, a subproduct of the food industry and a protein, possesses limited applications due to its high hydrophobic character. The objective of this research was to investigate the influence of homogenization pressure and cycles on the volumetric mean diameter (D4,3), span [...] Read more.
Zein, a subproduct of the food industry and a protein, possesses limited applications due to its high hydrophobic character. The objective of this research was to investigate the influence of homogenization pressure and cycles on the volumetric mean diameter (D4,3), span values, and Turbiscan Stability Index (TSI) using the response surface methodology for microfluidized emulsions containing zein as a unique stabilizer. Results showed that homogenization pressure seems to be the most influential parameter to obtain enhanced physical stability and droplet size distributions, with the optimum being 20,000 psi. Interestingly, the optimum number of cycles for volumetric diameter, span value, and TSI is not the same. Although a decrease of D4,3 with number of cycles is observed (optimum three cycles), this provokes an increase of span values (optimum one cycle) due to the recoalescence effect. Since physical stability is influenced by D4,3 and span, the minimum for TSI is observed at the middle level of the cycles (2 cycles). This work highlights that not only volumetric diameter, but also span value must be taken into consideration in order to obtain stable zein emulsions. In addition, this study wants to extend the limited knowledge about zein-based emulsions processed with a Microfluidizer device. Full article
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11 pages, 3269 KiB  
Article
Relating Amorphous Structure to the Tear Strength of Polylactic Acid Films
by Yutaka Kobayashi, Akira Ishigami and Hiroshi Ito
Polymers 2022, 14(10), 1965; https://doi.org/10.3390/polym14101965 - 11 May 2022
Cited by 5 | Viewed by 2284
Abstract
Compared with polyolefins that are used as single-use plastics, polylactic acid (PLA) has a lower tear strength in films. The relationship between the tear strength and the higher-order structure of films was investigated using PLA films that absorbed moisture at 30 °C and [...] Read more.
Compared with polyolefins that are used as single-use plastics, polylactic acid (PLA) has a lower tear strength in films. The relationship between the tear strength and the higher-order structure of films was investigated using PLA films that absorbed moisture at 30 °C and 95% relative humidity (RH) or that had been annealed under reduced pressure conditions. Although the mobile amorphous (MAm) amount did not change under high humidity, the film became brittle due to enthalpy relaxation. The crystallization by annealing also caused embrittlement, and the MAm amount decreased to 10%. The displacement until tearing is lowered from 2.5 to 0.5 mm in both cases. However, in situ retardation measurements revealed that there was a significant difference in the fracture morphology of the torn tip. When crystallized, the molecular chains and crystals are oriented in the tensile direction of the film, and a fragmented structure is observed in the ligament. Embrittlement due to enthalpy relaxation caused a weak orientation perpendicular to the tensile direction of the film, and cracks occurs along with this orientation. Full article
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14 pages, 4317 KiB  
Article
Amelioration of Obesity in Mice Fed a High-Fat Diet with Uronic Acid–Rich Polysaccharides Derived from Tremella fuciformis
by Chun-Hui Chiu, Kai-Chu Chiu and Li-Chan Yang
Polymers 2022, 14(8), 1514; https://doi.org/10.3390/polym14081514 - 8 Apr 2022
Cited by 9 | Viewed by 3223
Abstract
Obesity is rapidly becoming an emerging disease in developing countries due to the Westernization of societies and lifestyle changes. This study evaluated the ameliorative effect of acidic heteropolysaccharides derived from Tremella fuciformis (TFPS) on high-fat diet (HFD; 34.9% fat)-induced obesity in mice. The [...] Read more.
Obesity is rapidly becoming an emerging disease in developing countries due to the Westernization of societies and lifestyle changes. This study evaluated the ameliorative effect of acidic heteropolysaccharides derived from Tremella fuciformis (TFPS) on high-fat diet (HFD; 34.9% fat)-induced obesity in mice. The TFPS exhibited high uronic acid content and high viscosity in water. The structural characteristics of TFPS showed that average molecular weight was 679 kDa, and the monosaccharide composition was galactose, glucose, fructose, xylose, fucose, and mannose at a ratio of 1.0:6.5:10.0:18.5:30.5:67.5. In an in vivo study, HFD-induced obese C57BL/6 mice were orally given a TFPS treatment at 1 and 2 g/kg of body weight for 8 weeks. The TFPS treatment significantly reduced features of obesity in the mice, namely weight gain, feed efficiency, body fat percentage, and serum cholesterol level and increased fecal lipid content, compared with mice fed an HFD with water. In addition, TFPS exhibited the inhibition of cholesterol micelles in vitro in a concentration-dependent manner. In conclusion, the TFPS treatment ameliorated the diet-induced obesity in the mice, presumably reducing fat absorption in the intestine by interfering with viscous TFPS. Full article
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15 pages, 3412 KiB  
Article
Sequencing Biodegradable and Potentially Biobased Polyesteramide of Sebacic Acid and 3-Amino-1-propanol by MALDI TOF-TOF Tandem Mass Spectrometry
by Paola Rizzarelli, Stefania La Carta, Emanuele Francesco Mirabella, Marco Rapisarda and Giuseppe Impallomeni
Polymers 2022, 14(8), 1500; https://doi.org/10.3390/polym14081500 - 7 Apr 2022
Cited by 4 | Viewed by 2521
Abstract
Biodegradable and potentially biobased polyesteramide oligomers (PEA-Pro), obtained from melt condensation of sebacic acid and 3-amino-1-propanol, were characterized by nuclear magnetic resonance (NMR), matrix assisted laser desorption/ionization-time of flight/time of flight-mass spectrometry/mass spectrometry (MALDI-TOF/TOF-MS/MS), thermogravimetric analysis (TGA), and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). NMR [...] Read more.
Biodegradable and potentially biobased polyesteramide oligomers (PEA-Pro), obtained from melt condensation of sebacic acid and 3-amino-1-propanol, were characterized by nuclear magnetic resonance (NMR), matrix assisted laser desorption/ionization-time of flight/time of flight-mass spectrometry/mass spectrometry (MALDI-TOF/TOF-MS/MS), thermogravimetric analysis (TGA), and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). NMR analysis showed the presence of hydroxyl and amino terminal groups as well as carboxylic groups of the sebacate moiety. Hydroxyl and carboxyl termination had the same abundance, while the amine termination was 2.7-times less frequent. Information regarding the fragmentation pathways and ester/amide bond sequences was obtained by MALDI-TOF/TOF-MS/MS analysis performed on sodiated adducts of cyclic species and linear oligomers. Different end groups did not influence the observed fragmentation. Three fragmentation pathways were recognized. The β-hydrogen-transfer rearrangement, which leads to the selective scission of the –O–CH2– bonds, was the main mechanism. Abundant product ions originating from –CH2–CH2– (β–γ) bond cleavage in the sebacate moiety and less abundant ions formed by –O–CO– cleavages were also detected. TGA showed a major weight loss (74%) at 381 °C and a second degradation step (22% weight loss) at 447 °C. Py-GC/MS performed in the temperature range of 350–400 °C displayed partial similarity between the degradation products and the main fragments detected in the MALDI-TOF/TOF-MS/MS experiments. Degradation products derived from amide bonds were related to the formation of CN groups, in agreement with the literature. Full article
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13 pages, 3853 KiB  
Article
Effect of Antibacterial Peptide Microsphere Coating on the Microbial and Physicochemical Characteristics of Tricholoma matsutake during Cold Storage
by Hongli Li, Yan Feng, Peng Zhang, Mingwei Yuan and Minglong Yuan
Polymers 2022, 14(1), 208; https://doi.org/10.3390/polym14010208 - 5 Jan 2022
Cited by 6 | Viewed by 2502
Abstract
The effect of novel antimicrobial peptides (AMPs) and antimicrobial peptide microspheres (AMS) on the physicochemical and microbial quality of Tricholoma matsutake wild edible mushrooms was investigated. In the experiments, 1.0 g/L, 0.5 g/L of AMS, and 1.0 g/L AMPs were used as preservatives. [...] Read more.
The effect of novel antimicrobial peptides (AMPs) and antimicrobial peptide microspheres (AMS) on the physicochemical and microbial quality of Tricholoma matsutake wild edible mushrooms was investigated. In the experiments, 1.0 g/L, 0.5 g/L of AMS, and 1.0 g/L AMPs were used as preservatives. Mushrooms coated with 1.0 g/L and 0.5 g/L of AMS as a preservative had better physicochemical and sensory qualities than did mushrooms coated with 1.0 g/L of AMPs. In the experiment, 1.0 g/L of blank microspheres without cathelicidin-BF-30 (PLGA-1.0) and distilled water was used as the control. Samples with these two treatments had minimal changes in texture, weight loss, total bacteria count, and sensory attributes. Research results suggests that the use of AMS can maintain the quality of Tricholoma matsutake wild edible mushrooms and could extend the postharvest life to 20 d. Full article
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24 pages, 7806 KiB  
Article
Preparation and Characterization of an Injectable and Photo-Responsive Chitosan Methacrylate/Graphene Oxide Hydrogel: Potential Applications in Bone Tissue Adhesion and Repair
by Daniela N. Céspedes-Valenzuela, Santiago Sánchez-Rentería, Javier Cifuentes, Mónica Gantiva-Diaz, Julian A. Serna, Luis H. Reyes, Carlos Ostos, Christian Cifuentes-De la Portilla, Carolina Muñoz-Camargo and Juan C. Cruz
Polymers 2022, 14(1), 126; https://doi.org/10.3390/polym14010126 - 30 Dec 2021
Cited by 24 | Viewed by 4824
Abstract
As life expectancy continues to increase, the inevitable weakening and rupture of bone tissue have grown as concerns in the medical community, thus leading to the need for adhesive materials suitable for bone repair applications. However, current commercially available adhesives face certain drawbacks [...] Read more.
As life expectancy continues to increase, the inevitable weakening and rupture of bone tissue have grown as concerns in the medical community, thus leading to the need for adhesive materials suitable for bone repair applications. However, current commercially available adhesives face certain drawbacks that prevent proper tissue repair, such as low biocompatibility, poor adhesion to wet surfaces, and the need for high polymerization temperatures. This work aims to develop an injectable and photo-responsive chitosan methacrylate/graphene oxide (ChiMA/GO) adhesive nanocomposite hydrogel of high biocompatibility that is easy to apply by simple extrusion and that offers the possibility for in situ polymer and physiological temperatures. The nanocomposite was thoroughly characterized spectroscopically, microscopically, rheologically, thermally, and through mechanical, textural, and biological assays to fully evaluate its correct synthesis and functionalization and its performance under physiological conditions that mimic those observed in vivo. In addition, a finite element analysis (FEA) simulation was used to evaluate its performance in femur fractures. Results suggest the material’s potential as a bioadhesive, as it can polymerize at room temperature, shows superior stability in physiological media, and is capable of withstanding loads from body weight and movement. Moreover, the material showed remarkable biocompatibility as evidenced by low hemolytic and intermediate platelet aggregation tendencies, and high cytocompatibility when in contact with osteoblasts. The comprehensive studies presented here strongly suggest that the developed hydrogels are promising alternatives to conventional bone adhesives that might be further tested in vivo in the near future. Full article
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16 pages, 1537 KiB  
Article
Populus alba L., an Autochthonous Species of Spain: A Source for Cellulose Nanofibers by Chemical Pretreatment
by David Ibarra, Raquel Martín-Sampedro, Bernd Wicklein, Antonio M. Borrero-López, Concepción Valencia, Ana Valdehíta, José M. Navas and María E. Eugenio
Polymers 2022, 14(1), 68; https://doi.org/10.3390/polym14010068 - 25 Dec 2021
Cited by 6 | Viewed by 3111
Abstract
In order to identify new sustainable sources for producing cellulose nanofibers (CNFs), fast-growing poplar (Populus alba L.) wood was evaluated herein. For that purpose, bleached poplar kraft pulp was produced and submitted to TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical) mediated oxidation (TEMPO-ox) chemical pretreatment followed [...] Read more.
In order to identify new sustainable sources for producing cellulose nanofibers (CNFs), fast-growing poplar (Populus alba L.) wood was evaluated herein. For that purpose, bleached poplar kraft pulp was produced and submitted to TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical) mediated oxidation (TEMPO-ox) chemical pretreatment followed by microfluidization. The resulting CNFs were thoroughly characterized, including a rheological study at different pH values. Poplar CNFs showed properties comparable to eucalypt CNFs (reference material for CNFs production), showing high carboxylate content (1048 ± 128 µmol g−1), fibrillation yield (87.3% ± 8.1%), optical transmittance (83% at 700 nm) and thermal stability (up to more than 200 °C). Regarding the rheological study, whereas pH from 4 to 10 did not produce significant changes in rheological behavior, a reduction of pH down to 1 led to an order-of-magnitude increase on the viscoelastic functions. Therefore, poplar CNF shows potential in the pH-sensitive hydrogels application field. Finally, the possible ecotoxicity of poplar CNF was assessed. The decrease in cell viability was very low so that only concentrations causing a 10% cytotoxicity could be calculated for the assay detecting alterations in cell metabolism (10 µg mL−1) and plasma membrane integrity (60 µg mL−1). Full article
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14 pages, 3443 KiB  
Article
Preparation, Characterisation and Antibacterial Activity of Carvacrol Encapsulated in Gellan Gum Hydrogel
by Adila Mohamad Jaafar, Norafida Hasnu, Zulkarnain Zainal, Mas Jaffri Masarudin, Mohd Mokrish Md. Ajat, Min Min Aung and Marwah Rayung
Polymers 2021, 13(23), 4153; https://doi.org/10.3390/polym13234153 - 27 Nov 2021
Cited by 9 | Viewed by 2586
Abstract
Recently, the antibacterial properties of Carvacrol (Carv) have been significantly reported. However, due to the unstable properties of Carv under various environment conditions, research approaches tailored towards its widespread and efficient use in various antimicrobial applications are scarce. Here, we discuss progress towards [...] Read more.
Recently, the antibacterial properties of Carvacrol (Carv) have been significantly reported. However, due to the unstable properties of Carv under various environment conditions, research approaches tailored towards its widespread and efficient use in various antimicrobial applications are scarce. Here, we discuss progress towards overcoming this challenge by utilising the encapsulation of Carv in gellan gum hydrogels to form thin films (GG-Carv) containing different concentrations of Carv (0.01–0.32 M). FTIR spectrum of GG-Carv revealed that both functional groups from GG and Carv existed. The carbon, hydrogen and nitrogen elemental analysis further supported the encapsulation of Carv with the changes in the element percentage of GG-Carv. Both swelling and degradation percentage increased with time and the decreasing patterns were observed as the concentration of Carv increased. In an antibacterial study, GG-Carv exhibited significant antibacterial activity against E. coli with the clear inhibition zone of 200 mm and the detection of bacterial growth showed enhancement with continuous decline throughout the study as compared to free-standing Carv. Full article
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30 pages, 6633 KiB  
Article
An Insight into a Sustainable Removal of Bisphenol A from Aqueous Solution by Novel Palm Kernel Shell Magnetically Induced Biochar: Synthesis, Characterization, Kinetic, and Thermodynamic Studies
by Kamil Kayode Katibi, Khairul Faezah Yunos, Hasfalina Che Man, Ahmad Zaharin Aris, Mohd Zuhair Mohd Nor and Rabaah Syahidah Azis
Polymers 2021, 13(21), 3781; https://doi.org/10.3390/polym13213781 - 31 Oct 2021
Cited by 24 | Viewed by 3038
Abstract
Recently Bisphenol A (BPA) is one of the persistent trace hazardous estrogenic contaminants in the environment, that can trigger a severe threat to humans and environment even at minuscule concentrations. Thus, this work focused on the synthesis of neat and magnetic biochar (BC) [...] Read more.
Recently Bisphenol A (BPA) is one of the persistent trace hazardous estrogenic contaminants in the environment, that can trigger a severe threat to humans and environment even at minuscule concentrations. Thus, this work focused on the synthesis of neat and magnetic biochar (BC) as a sustainable and inexpensive adsorbent to remove BPA from aqueous environment. Novel magnetic biochar was efficiently synthesized by utilizing palm kernel shell, using ferric chloride and ferrous chloride as magnetic medium via chemical co-precipitation technique. In this experimental study, the influence of operating factors comprising contact time (20–240 min), pH (3.0–12.0), adsorbent dose (0.2–0.8 g), and starting concentrations of BPA (8.0–150 ppm) were studied in removing BPA during batch adsorption system using neat biochar and magnetic biochar. It was observed that the magnetically loaded BC demonstrates superior maximum removal efficiency of BPA with 94.2%, over the neat biochar. The functional groups (FTIR), Zeta potential, vibrating sample magnetometer (VSM), surface and textural properties (BET), surface morphology, and mineral constituents (FESEM/EDX), and chemical composition (XRD) of the adsorbents were examined. The experimental results demonstrated that the sorption isotherm and kinetics were suitably described by pseudo-second-order model and Freundlich model, respectively. By studying the adsorption mechanism, it was concluded that π-π electron acceptor–donor interaction (EAD), hydrophobic interaction, and hydrogen bond were the principal drives for the adsorption of BPA onto the neat BC and magnetic BC. Full article
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15 pages, 5007 KiB  
Article
Cytocompatibility of Polymethyl Methacrylate Honeycomb-like Pattern on Perfluorinated Polymer
by Klaudia Hurtuková, Veronika Juřicová, Klára Fajstavrová, Dominik Fajstavr, Nikola Slepičková Kasálková, Silvie Rimpelová, Václav Švorčík and Petr Slepička
Polymers 2021, 13(21), 3663; https://doi.org/10.3390/polym13213663 - 24 Oct 2021
Cited by 4 | Viewed by 2282
Abstract
In this study, we present a simple approach for developing a biocompatible polymer scaffold with a honeycomb-like micropattern. We aimed to combine a plasma treatment of fluorinated ethylene propylene (FEP) substrate with an improved phase separation technique. The plasma exposure served for modification [...] Read more.
In this study, we present a simple approach for developing a biocompatible polymer scaffold with a honeycomb-like micropattern. We aimed to combine a plasma treatment of fluorinated ethylene propylene (FEP) substrate with an improved phase separation technique. The plasma exposure served for modification of the polymer surface properties, such as roughness, surface chemistry, and wettability. The treated FEP substrate was applied for the growth of a honeycomb-like pattern from a solution of polymethyl methacrylate (PMMA). The properties of the pattern were strongly dependent on the conditions of plasma exposure of the FEP substrate. The physico-chemical properties of the prepared pattern, such as changes in wettability, aging, morphology, and surface chemistry, were determined. Further, we have examined the cellular response of human osteoblasts (U-2 OS) on the modified substrates. The micropattern prepared with a selected combination of surface activation and amount of PMMA for honeycomb construction showed a positive effect on U-2 OS cell adhesion and proliferation. Samples with higher PMMA content (3 and 4 g) formed more periodic hexagonal structures on the surface compared to its lower amount (1 and 2 g), which led to a significant increase in the pattern cytocompatibility compared to pristine or plasma-treated FEP. Full article
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17 pages, 5012 KiB  
Article
Development of Biodegradable Bio-Based Composite for Bone Tissue Engineering: Synthesis, Characterization and In Vitro Biocompatible Evaluation
by Muhammad Umar Aslam Khan, Saiful Izwan Abd Razak, Mohamed Nainar Mohamed Ansari, Razauden Mohamed Zulkifli, Nurliyana Ahmad Zawawi and Muhammad Arshad
Polymers 2021, 13(21), 3611; https://doi.org/10.3390/polym13213611 - 20 Oct 2021
Cited by 40 | Viewed by 3061
Abstract
Several significant advancements in the field of bone regenerative medicine have been made in recent years. However, therapeutic options, such as bone grafts, have several drawbacks. There is a need to develop an adequate bone substitute. As a result, significant bone defects/injuries pose [...] Read more.
Several significant advancements in the field of bone regenerative medicine have been made in recent years. However, therapeutic options, such as bone grafts, have several drawbacks. There is a need to develop an adequate bone substitute. As a result, significant bone defects/injuries pose a severe challenge for orthopaedic and reconstructive bone tissue. We synthesized polymeric composite material from arabinoxylan (ARX), β-glucan (BG), nano-hydroxyapatite (nHAp), graphene oxide (GO), acrylic acid (AAc) through free radical polymerization and porous scaffold fabricated using the freeze-drying technique. These fabricated porous scaffolds were then coated with chitosan solution to enhance their biological activities. The complex structure of BG, nHAp, GO was studied through various characterization and biological assays. The structural, morphological, wetting and mechanical analyses were determined using FT-IR, XRD, XPS, SEM/EXD, water contact angle and UTM. The swelling (aqueous and PBS media) and degradation (PBS media) observed their behavior in contact with body fluid. The biological activities were conducted against mouse pre-osteoblast cell lines. The result found that BGH3 has desirable morphological, structural with optimum swelling, degradation, and mechanical behavior. It was also found to be cytocompatible against MC3T3-E1 cell lines. The obtained results confirmed that the fabricated polymeric scaffolds would be a potential bone substitute to regenerate defective bone with different loading bearing applications for bone tissue engineering. Full article
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15 pages, 11194 KiB  
Article
Properties of Particleboard from Oil Palm Biomasses Bonded with Citric Acid and Tapioca Starch
by Radiah Zakaria, Paiman Bawon, Seng Hua Lee, Sabiha Salim, Wei Chen Lum, Syeed Saifulazry Osman Al-Edrus and Zawawi Ibrahim
Polymers 2021, 13(20), 3494; https://doi.org/10.3390/polym13203494 - 12 Oct 2021
Cited by 16 | Viewed by 2899
Abstract
The study investigated the effects of the addition of starch on the properties of oil palm biomass particleboard bonded with citric acid. Three kinds of oil palm biomasses were used in this study for the fabrication of particleboard, namely, oil palm frond (OPF), [...] Read more.
The study investigated the effects of the addition of starch on the properties of oil palm biomass particleboard bonded with citric acid. Three kinds of oil palm biomasses were used in this study for the fabrication of particleboard, namely, oil palm frond (OPF), oil palm trunk (OPT), and empty fruit bunch (EFB) particles. Citric acid and tapioca starch at the mixing ratios of 100:0, 87.5:12.5, and 75:25 were prepared at a 60% solid content. A 30% resin content based on the oven-dried weight of the oil palm biomass particles was used. The sprayed particles were pre-dried at 80 °C for 12 h before being hot-pressed at 180 °C and 4 MPa pressure for 10 min. The physical and mechanical properties of the particleboard were evaluated. The mixtures of citric acid and tapioca starch were characterized by thermogravimetric analysis (TGA). Thermal stability of citric acid was reduced after the addition of tapioca starch. The addition of 12.5% tapioca starch improved the bending strength of the particleboard but increased the thickness swelling slightly. All UF-bonded particleboard exhibited significantly inferior performance than that of citric-acid-bonded particleboard. Citric-acid-bonded particleboard maintained its original shape after being subjected to a cyclic-aging treatment, while the UF-bonded particleboard disintegrated half way through the treatment. The performance of EFB particleboard was significantly inferior to its OPT and OPF counterparts. Full article
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12 pages, 6835 KiB  
Article
Influence of Formate Concentration on the Rheology and Thermal Degradation of Xanthan Gum
by María José Martín-Alfonso, Javier Mauricio Loaiza, Clara Delgado-Sánchez and Francisco José Martínez-Boza
Polymers 2021, 13(19), 3378; https://doi.org/10.3390/polym13193378 - 30 Sep 2021
Cited by 4 | Viewed by 2283
Abstract
Xanthan gum solutions have gained increasing interest for their use as environmentally friendly chemicals in the oil industry. Xanthan is compatible with most concentrate brines used for controlling formation damage and fluid loss. Particularly, formate brines reinforce the ordered structure of the biopolymer [...] Read more.
Xanthan gum solutions have gained increasing interest for their use as environmentally friendly chemicals in the oil industry. Xanthan is compatible with most concentrate brines used for controlling formation damage and fluid loss. Particularly, formate brines reinforce the ordered structure of the biopolymer in solution, gel strength, and the specific gravity of the resulting fluid. In this paper, we studied the effect of thermal aging on the rheological behavior of xanthan solutions as a function of the concentration in potassium formate. Ionic strength below a threshold concentration does not prevent the degradation of the structure of xanthan after being submitted to aging at 165 °C. Aged solutions show an important loss of strength in their mechanical properties, lower pH, and higher content in furfural and hydroxymethylfurfural. Highly concentrated formate brines are necessary to maintain the strength of the rheological properties after exposure to high-temperature environments. Full article
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26 pages, 4657 KiB  
Article
Microwave Enabled Physically Cross Linked Sodium Alginate and Pectin Film and Their Application in Combination with Modified Chitosan-Curcumin Nanoparticles. A Novel Strategy for 2nd Degree Burns Wound Healing in Animals
by Hafiz Muhammad Basit, Muhammad Ali, Mian Mufarih Shah, Shefaat Ullah Shah, Abdul Wahab, Hassan A. Albarqi, Abdulsalam A. Alqahtani, Ismail A. Walbi and Nauman Rahim Khan
Polymers 2021, 13(16), 2716; https://doi.org/10.3390/polym13162716 - 13 Aug 2021
Cited by 15 | Viewed by 2889
Abstract
This study reports microwave assisted physically cross-linked sodium alginate and pectin film and their testing in combination with modified chitosan-curcumin nanoparticles for skin tissue regeneration following 2nd degree burn wound. Film was formulated by solution casting method and physically cross-linked using microwave irradiation [...] Read more.
This study reports microwave assisted physically cross-linked sodium alginate and pectin film and their testing in combination with modified chitosan-curcumin nanoparticles for skin tissue regeneration following 2nd degree burn wound. Film was formulated by solution casting method and physically cross-linked using microwave irradiation at frequency of 2450 MHz, power 750 Watt for different time intervals for optimization. The optimized formulation was analyzed for various physiochemical attributes. Afterwards, the optimized film and optimized modified chitosan-curcumin nanoparticles were tested in combination for skin regeneration potential following burn wound in vivo and skin samples extracted and tested for different attributes. The results indicated that the optimized film formulation (5 min microwave treatment) physicochemical attributes significantly enhanced addressing the properties required of a wound healing platform. The vibrational analysis indicated that the optimized film experienced significant rigidification of hydrophilic domains while the hydrophobic domains underwent significant fluidization which also resulted in significant increase in the transition temperatures and system enthalpies of both polymer moieties with microwave treatment. The combined film and nanoparticles application significantly increased protein content in the wounds which were evident from higher absorbance ratios of amide-I and amide-II (2.15 ± 0.001), significantly higher melting transition temperature and enthalpy (∆T = 167.2 ± 15.4 °C, ∆H = 510.7 ± 20.1 J/g) and higher tensile strength (14.65 ± 0.8 MPa) with significantly enhanced percent re-epithelization (99.9934 ± 2.56) in comparison to other treatments. The combined application of film and nanoparticles may prove to be a new novel treatment strategy for 2nd degree burn wound healing. Full article
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13 pages, 2286 KiB  
Article
Bioethanol Production and Alkali Pulp Processes as Sources of Anionic Lignin Surfactants
by Rodrigo Álvarez-Barajas, Antonio A. Cuadri, Francisco J. Navarro, Francisco J. Martínez-Boza and Pedro Partal
Polymers 2021, 13(16), 2703; https://doi.org/10.3390/polym13162703 - 13 Aug 2021
Cited by 1 | Viewed by 1777
Abstract
Lignin is an abundant biopolymer with potential value-added applications that depend on biomass source and fractioning method. This work explores the use as emulsifiers of three native lignin-rich product coming from industrial bioethanol production and alkali or Kraft pulping. In addition to their [...] Read more.
Lignin is an abundant biopolymer with potential value-added applications that depend on biomass source and fractioning method. This work explores the use as emulsifiers of three native lignin-rich product coming from industrial bioethanol production and alkali or Kraft pulping. In addition to their distinctive characteristics, the different molecular organization induced by emulsification pH is expected to interact in various ways at the water-oil interface of the emulsion droplets. Initially, model oil-in-water (O/W) emulsions of a silicone oil will be studied as a function of lignin source, disperse phase concentration and emulsification pH. Once stablished the effect of such variables, emulsion formulations of three potential bitumen rejuvenators (waste vegetable cooking oil, recycled lubricating oil and a 160/220 penetration range soft bitumen). Droplet size distribution, Z-potential and viscous tests conducted on model emulsions have shown that emulsification pH strongly affects stabilization ability of the lignins tested. Regarding bitumen rejuvenators, lignin emulsification capability will be affected by surfactant source, pH and, additionally, by the dispersed phase characteristics. Lower Z-potential values shown by KL at pH 9 and 11 seem to facilitate emulsification of the less polar disperse phases formed by RLUB and bitumen. In any case, lower particle size and higher yield stress values were found for both bioethanol-derived lignins emulsifying RVO and RLUB at pH 13, which are expected to exhibit a longer stability. Full article
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19 pages, 3613 KiB  
Article
Study of Mechanical Properties of PHBHV/Miscanthus Green Composites Using Combined Experimental and Micromechanical Approaches
by Thibault Lemaire, Erica Gea Rodi, Valérie Langlois, Estelle Renard and Vittorio Sansalone
Polymers 2021, 13(16), 2650; https://doi.org/10.3390/polym13162650 - 10 Aug 2021
Cited by 5 | Viewed by 2379
Abstract
In recent years the interest in the realization of green wood plastic composites (GWPC) materials has increased due to the necessity of reducing the proliferation of synthetic plastics. In this work, we study a specific class of GWPCs from its synthesis to the [...] Read more.
In recent years the interest in the realization of green wood plastic composites (GWPC) materials has increased due to the necessity of reducing the proliferation of synthetic plastics. In this work, we study a specific class of GWPCs from its synthesis to the characterization of its mechanical properties. These properties are related to the underlying microstructure using both experimental and modeling approaches. Different contents of Miscanthus giganteus fibers, at 5, 10, 20, 30 weight percent’s, were thus combined to a microbial matrix, namely poly (3-hydroxybutyrate)-co-poly(3-hydroxyvalerate) (PHBHV). The samples were manufactured by extrusion and injection molding processing. The obtained samples were then characterized by cyclic-tensile tests, pycnometer testing, differential scanning calorimetry, Fourier transform infrared spectroscopy, X-ray diffraction, and microscopy. The possible effect of the fabrication process on the fibers size is also checked. In parallel, the measured properties of the biocomposite were also estimated using a Mori–Tanaka approach to derive the effective behavior of the composite. As expected, the addition of reinforcement to the polymer matrix results in composites with higher Young moduli on the one hand, and lower failure strains and tensile strengths on the other hand (tensile modulus was increased by 100% and tensile strength decreased by 23% when reinforced with 30 wt % of Miscanthus fibers). Full article
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17 pages, 20645 KiB  
Article
Comparative Study of the Properties of Wood Flour and Wood Pellets Manufactured from Secondary Processing Mill Residues
by Geeta Pokhrel, Yousoo Han and Douglas J. Gardner
Polymers 2021, 13(15), 2487; https://doi.org/10.3390/polym13152487 - 28 Jul 2021
Cited by 10 | Viewed by 4035
Abstract
The generation of secondary processing mill residues from wood processing facilities is extensive in the United States. Wood flour can be manufactured utilizing these residues and an important application of wood flour is as a filler in the wood–plastic composites (WPCs). Scientific research [...] Read more.
The generation of secondary processing mill residues from wood processing facilities is extensive in the United States. Wood flour can be manufactured utilizing these residues and an important application of wood flour is as a filler in the wood–plastic composites (WPCs). Scientific research on wood flour production from mill residues is limited. One of the greatest costs involved in the supply chain of WPCs manufacturing is the transportation cost. Wood flour, constrained by low bulk densities, is commonly transported by truck trailers without attaining allowable weight limits. Because of this, shipping costs often exceed the material costs, consequently increasing raw material costs for WPC manufacturers and the price of finished products. A bulk density study of wood flour (190–220 kg/m3) and wood pellets (700–750 kg/m3) shows that a tractor-trailer can carry more than three times the weight of pellets compared to flour. Thus, this study focuses on exploring the utilization of mill residues from four wood species in Maine to produce raw materials for manufacturing WPCs. Two types of raw materials for the manufacture of WPCs, i.e., wood flour and wood pellets, were produced and a study of their properties was performed. At the species level, red maple 40-mesh wood flour had the highest bulk density and lowest moisture content. Spruce-fir wood flour particles were the finest (dgw of 0.18 mm). For all species, the 18–40 wood flour mesh size possessed the highest aspect ratio. Similarly, on average, wood pellets manufactured from 40-mesh particles had a lower moisture content, higher bulk density, and better durability than the pellets from unsieved wood flour. Red maple pellets had the lowest moisture content (0.12%) and the highest bulk density (738 kg/m3). The results concluded that the processing of residues into wood flour and then into pellets reduced the moisture content by 76.8% and increased the bulk density by 747%. These material property parameters are an important attempt to provide information that can facilitate the more cost-efficient transport of wood residue feedstocks over longer distances. Full article
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20 pages, 4957 KiB  
Article
The Effect of Cellulose Nanocrystal Suspension Treatment on Suspension Viscosity and Casted Film Property
by Yucheng Peng and Brian Via
Polymers 2021, 13(13), 2168; https://doi.org/10.3390/polym13132168 - 30 Jun 2021
Cited by 19 | Viewed by 3068
Abstract
Cellulose nanocrystals (CNCs) have attracted significant interest in different industrial sectors. Many applications have been developed and more are being explored. Pre-treatment of the suspension plays a critical role for different applications. In this study, different pre-treatment methods, including homogenization, ultrasonication, and mixing [...] Read more.
Cellulose nanocrystals (CNCs) have attracted significant interest in different industrial sectors. Many applications have been developed and more are being explored. Pre-treatment of the suspension plays a critical role for different applications. In this study, different pre-treatment methods, including homogenization, ultrasonication, and mixing with a magnetic stirrer were applied to a CNC suspension. After treatment, the rheological behaviors of the treated CNC suspensions were characterized using a rotational viscometer. The treated suspensions were then used to cast films for characterization by ultraviolet-visible (UV-Vis) and Fourier transform near-infrared spectroscopy (FT-NIR). All the CNC suspensions demonstrated a shear thinning phenomena. Homogenization or ultrasonication significantly decreased the suspension viscosity compared with the suspension mixed by a magnetic stirrer. The viscosity of CNC suspension changed with time after treatment and settlement of treated CNC suspensions in room conditions increased the viscosity dramatically with time. Different UV and visible light interferences were observed for the CNC films generated from suspensions treated by different methods. The degree of crystallinity of the CNC films evaluated by FT-NIR showed that the film from suspension treated by homogenization and ultrasonication has the highest degree of crystallinity. Pre-treatments of CNC suspension affected the suspension viscosities and formed film properties. Full article
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18 pages, 5447 KiB  
Article
Novel Mangosteen-Leaves-Based Marker Ink: Color Lightness, Viscosity, Optimized Composition, and Microstructural Analysis
by Mohd Salahuddin Mohd Basri, Brenda Liew Min Ren, Rosnita A. Talib, Rabitah Zakaria and Siti Hasnah Kamarudin
Polymers 2021, 13(10), 1581; https://doi.org/10.3390/polym13101581 - 14 May 2021
Cited by 6 | Viewed by 15451
Abstract
Dry mangosteen leaves are one of the raw materials used to produce marker ink. However, research using this free and abundant resource is rather limited. The less efficient one-factor-at-a-time (OFAT) approach was mostly used in past studies on plant-based marker ink. The use [...] Read more.
Dry mangosteen leaves are one of the raw materials used to produce marker ink. However, research using this free and abundant resource is rather limited. The less efficient one-factor-at-a-time (OFAT) approach was mostly used in past studies on plant-based marker ink. The use of statistical analysis and the regression coefficient model (mathematical model) was considered essential in predicting the best combination of factors in formulating mangosteen leaf-based marker ink. Ideally, ink should have maximum color lightness, minimum viscosity, and fast-drying speed. The objective of this study to study the effect of glycerol and carboxymethyl cellulose (CMC) on the color lightness and viscosity of mangosteen-leaves-based marker ink. The viscosity, color lightness, and drying properties of the ink were tested, the significant effect of glycerol and CMC (responses) on ink properties was identified and the prediction model on the optimum value of the responses was developed by using response surface methodology (RSM). The microstructure of mangosteen leaves was analyzed to study the surface morphology and cell structure during dye extraction. A low amount of glycerol used was found to increase the value of color lightness. A decrease in CMC amounts resulted in low viscosity of marker ink. The optimum formulation for the ink can be achieved when the weight percents of glycerol, benzalkonium chloride, ferrous sulphate, and CMC are set at 5, 5, 1, and 3, respectively. SEM micrographs showed the greatest amount of cell wall structure collapse on samples boiled with the lowest amount of glycerol. Full article
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Review

Jump to: Editorial, Research

40 pages, 41219 KiB  
Review
A Review of Rigid Polymeric Cellular Foams and Their Greener Tannin-Based Alternatives
by Antonio M. Borrero-López, Vincent Nicolas, Zelie Marie, Alain Celzard and Vanessa Fierro
Polymers 2022, 14(19), 3974; https://doi.org/10.3390/polym14193974 - 23 Sep 2022
Cited by 13 | Viewed by 3944
Abstract
This review focuses on the description of the main processes and materials used for the formulation of rigid polymer foams. Polyurethanes and their derivatives, as well as phenolic systems, are described, and their main components, foaming routes, end of life, and recycling are [...] Read more.
This review focuses on the description of the main processes and materials used for the formulation of rigid polymer foams. Polyurethanes and their derivatives, as well as phenolic systems, are described, and their main components, foaming routes, end of life, and recycling are considered. Due to environmental concerns and the need to find bio-based alternatives for these products, special attention is given to a recent class of polymeric foams: tannin-based foams. In addition to their formulation and foaming procedures, their main structural, thermal, mechanical, and fire resistance properties are described in detail, with emphasis on their advanced applications and recycling routes. These systems have been shown to possess very interesting properties that allow them to be considered as potential substitutes for non-renewable rigid polymeric cellular foams. Full article
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22 pages, 1953 KiB  
Review
Potential Medical Applications of Chitooligosaccharides
by Sukumaran Anil
Polymers 2022, 14(17), 3558; https://doi.org/10.3390/polym14173558 - 29 Aug 2022
Cited by 28 | Viewed by 4179
Abstract
Chitooligosaccharides, also known as chitosan oligomers or chitooligomers, are made up of chitosan with a degree of polymerization (DP) that is less than 20 and an average molecular weight (MW) that is lower than 3.9 kDa. COS can be produced through enzymatic conversions [...] Read more.
Chitooligosaccharides, also known as chitosan oligomers or chitooligomers, are made up of chitosan with a degree of polymerization (DP) that is less than 20 and an average molecular weight (MW) that is lower than 3.9 kDa. COS can be produced through enzymatic conversions using chitinases, physical and chemical applications, or a combination of these strategies. COS is of significant interest for pharmacological and medical applications due to its increased water solubility and non-toxicity, with a wide range of bioactivities, including antibacterial, anti-inflammatory, anti-obesity, neuroprotective, anticancer, and antioxidant effects. This review aims to outline the recent advances and potential applications of COS in various diseases and conditions based on the available literature, mainly from preclinical research. The prospects of further in vivo studies and translational research on COS in the medical field are highlighted. Full article
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25 pages, 3808 KiB  
Review
Recent Advances in 3D Bioprinting: A Review of Cellulose-Based Biomaterials Ink
by Wan Nazihah Liyana Wan Jusoh, Mohd Shaiful Sajab, Peer Mohamed Abdul and Hatika Kaco
Polymers 2022, 14(11), 2260; https://doi.org/10.3390/polym14112260 - 31 May 2022
Cited by 14 | Viewed by 4296
Abstract
Cellulose-based biodegradable hydrogel proves to be excellently suitable for the medical and water treatment industry based on the expressed properties such as its flexible structure and broad compatibility. Moreover, their potential to provide excellent waste management from the unutilized plant has triggered further [...] Read more.
Cellulose-based biodegradable hydrogel proves to be excellently suitable for the medical and water treatment industry based on the expressed properties such as its flexible structure and broad compatibility. Moreover, their potential to provide excellent waste management from the unutilized plant has triggered further study on the advanced biomaterial applications. To extend the use of cellulose-based hydrogel, additive manufacturing is a suitable technique for hydrogel fabrication in complex designs. Cellulose-based biomaterial ink used in 3D bioprinting can be further used for tissue engineering, drug delivery, protein study, microalgae, bacteria, and cell immobilization. This review includes a discussion on the techniques available for additive manufacturing, bio-based material, and the formation of a cellulose-based hydrogel. Full article
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17 pages, 1467 KiB  
Review
Recent Strategies for the Immobilization of Therapeutic Enzymes
by Chen-Yuan Zhu, Fei-Long Li, Ye-Wang Zhang, Rahul K. Gupta, Sanjay K. S. Patel and Jung-Kul Lee
Polymers 2022, 14(7), 1409; https://doi.org/10.3390/polym14071409 - 30 Mar 2022
Cited by 29 | Viewed by 5130
Abstract
Therapeutic enzymes play important roles in modern medicine due to their high affinity and specificity. However, it is very expensive to use them in clinical medicine because of their low stability and bioavailability. To improve the stability and effectiveness of therapeutic enzymes, immobilization [...] Read more.
Therapeutic enzymes play important roles in modern medicine due to their high affinity and specificity. However, it is very expensive to use them in clinical medicine because of their low stability and bioavailability. To improve the stability and effectiveness of therapeutic enzymes, immobilization techniques have been employed to enhance the applications of therapeutic enzymes in the past few years. Reported immobilization techniques include entrapment, adsorption, and covalent attachment. In addition, protein engineering is often used to improve enzyme properties; however, all methods present certain advantages and limitations. For carrier-bound immobilization, the delivery and release of the immobilized enzyme depend on the properties of the carrier and enzyme. In this review, we summarize the advantages and challenges of the current strategies developed to deliver therapeutic enzymes and provide a future perspective on the immobilization technologies used for therapeutic enzyme delivery. Full article
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42 pages, 3598 KiB  
Review
Lignocellulosic Materials for the Production of Biofuels, Biochemicals and Biomaterials and Applications of Lignocellulose-Based Polyurethanes: A Review
by Antonio M. Borrero-López, Concepción Valencia and José M. Franco
Polymers 2022, 14(5), 881; https://doi.org/10.3390/polym14050881 - 23 Feb 2022
Cited by 39 | Viewed by 6896
Abstract
The present review is devoted to the description of the state-of-the-art techniques and procedures concerning treatments and modifications of lignocellulosic materials in order to use them as precursors for biomaterials, biochemicals and biofuels, with particular focus on lignin and lignin-based products. Four different [...] Read more.
The present review is devoted to the description of the state-of-the-art techniques and procedures concerning treatments and modifications of lignocellulosic materials in order to use them as precursors for biomaterials, biochemicals and biofuels, with particular focus on lignin and lignin-based products. Four different main pretreatment types are outlined, i.e., thermal, mechanical, chemical and biological, with special emphasis on the biological action of fungi and bacteria. Therefore, by selecting a determined type of fungi or bacteria, some of the fractions may remain unaltered, while others may be decomposed. In this sense, the possibilities to obtain different final products are massive, depending on the type of microorganism and the biomass selected. Biofuels, biochemicals and biomaterials derived from lignocellulose are extensively described, covering those obtained from the lignocellulose as a whole, but also from the main biopolymers that comprise its structure, i.e., cellulose, hemicellulose and lignin. In addition, special attention has been paid to the formulation of bio-polyurethanes from lignocellulosic materials, focusing more specifically on their applications in the lubricant, adhesive and cushioning material fields. High-performance alternatives to petroleum-derived products have been reported, such as adhesives that substantially exceed the adhesion performance of those commercially available in different surfaces, lubricating greases with tribological behaviour superior to those in lithium and calcium soap and elastomers with excellent static and dynamic performance. Full article
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27 pages, 2536 KiB  
Review
A Comprehensive Review on Natural Fibers: Technological and Socio-Economical Aspects
by Azizatul Karimah, Muhammad Rasyidur Ridho, Sasa Sofyan Munawar, Ismadi, Yusup Amin, Ratih Damayanti, Muhammad Adly Rahandi Lubis, Asri Peni Wulandari, Nurindah, Apri Heri Iswanto, Ahmad Fudholi, Mochamad Asrofi, Euis Saedah, Nasmi Herlina Sari, Bayu Rizky Pratama, Widya Fatriasari, Deded Sarip Nawawi, Sanjay Mavinkere Rangappa and Suchart Siengchin
Polymers 2021, 13(24), 4280; https://doi.org/10.3390/polym13244280 - 7 Dec 2021
Cited by 67 | Viewed by 12978
Abstract
Asian countries have abundant resources of natural fibers, but unfortunately, they have not been optimally utilized. The facts showed that from 2014 to 2020, there was a shortfall in meeting national demand of over USD 2.75 million per year. Therefore, in order to [...] Read more.
Asian countries have abundant resources of natural fibers, but unfortunately, they have not been optimally utilized. The facts showed that from 2014 to 2020, there was a shortfall in meeting national demand of over USD 2.75 million per year. Therefore, in order to develop the utilization and improve the economic potential as well as the sustainability of natural fibers, a comprehensive review is required. The study aimed to demonstrate the availability, technological processing, and socio-economical aspects of natural fibers. Although many studies have been conducted on this material, it is necessary to revisit their potential from those perspectives to maximize their use. The renewability and biodegradability of natural fiber are part of the fascinating properties that lead to their prospective use in automotive, aerospace industries, structural and building constructions, bio packaging, textiles, biomedical applications, and military vehicles. To increase the range of applications, relevant technologies in conjunction with social approaches are very important. Hence, in the future, the utilization can be expanded in many fields by considering the basic characteristics and appropriate technologies of the natural fibers. Selecting the most prospective natural fiber for creating national products can be assisted by providing an integrated management system from a digitalized information on potential and related technological approaches. To make it happens, collaborations between stakeholders from the national R&D agency, the government as policy maker, and academic institutions to develop national bioproducts based on domestic innovation in order to move the circular economy forward are essential. Full article
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22 pages, 5054 KiB  
Review
Emergence of Polymeric Material Utilising Sustainable Radiation Curable Palm Oil-Based Products for Advanced Technology Applications
by Rida Tajau, Rosiah Rohani, Mohd Sofian Alias, Nurul Huda Mudri, Khairul Azhar Abdul Halim, Mohd Hamzah Harun, Naurah Mat Isa, Rosley Che Ismail, Sharilla Muhammad Faisal, Marina Talib, Muhammad Rawi Mohamed Zin, Izzati Izni Yusoff, Nadiah Khairul Zaman and Iqma Asyila Ilias
Polymers 2021, 13(11), 1865; https://doi.org/10.3390/polym13111865 - 4 Jun 2021
Cited by 14 | Viewed by 4596
Abstract
In countries that are rich with oil palm, the use of palm oil to produce bio-based acrylates and polyol can be the most eminent raw materials used for developing new and advanced natural polymeric materials involving radiation technique, like coating resins, nanoparticles, scaffold, [...] Read more.
In countries that are rich with oil palm, the use of palm oil to produce bio-based acrylates and polyol can be the most eminent raw materials used for developing new and advanced natural polymeric materials involving radiation technique, like coating resins, nanoparticles, scaffold, nanocomposites, and lithography for different branches of the industry. The presence of hydrocarbon chains, carbon double bonds, and ester bonds in palm oil allows it to open up the possibility of fine-tuning its unique structures in the development of novel materials. Cross-linking, reversible addition-fragmentation chain transfer (RAFT), polymerization, grafting, and degradation are among the radiation mechanisms triggered by gamma, electron beam, ultraviolet, or laser irradiation sources. These radiation techniques are widely used in the development of polymeric materials because they are considered as the most versatile, inexpensive, easy, and effective methods. Therefore, this review summarized and emphasized on several recent studies that have reported on emerging radiation processing technologies for the production of radiation curable palm oil-based polymeric materials with a promising future in certain industries and biomedical applications. This review also discusses the rich potential of biopolymeric materials for advanced technology applications. Full article
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