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1.
Int J Biol Macromol ; 279(Pt 2): 135312, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39236960

RESUMEN

Sensing motors and supercapacitors are pivotal in empowering smart systems, honing energy management, and facilitating the seamless integration of responsive electronics. Harnessing the electrochemistry of methylcellulose-polyaniline (MC/PANI) composites, this research delves into their potential applications as reactive current sensing supercapacitors with single connectivity. The electrochemical traits of pristine polyaniline (PANI) and MC/PANI composites were analyzed and assessed for their potential applications in sensors and energy storage devices. With a specific capacitance of 300Fg-1, the MC/PANI_B3 composite-based device retained 87.01 % capacitance after 2000 cycles. Besides, based on electrical energy as the sensing parameter, the composite exhibited augmented cathodic and anodic current sensitivity of 8.77 mJmA-1 and -8.86 mJmA-1, respectively. The ameliorated supercapacitor and current sensing parameters of MC/PANI_B3 are ascribed to the percolation threshold content of the conducting phase, which is endowed with optimal hydrogen bond-mediated interactions with methylcellulose (MC), thus confers an expanded chain conformation.

2.
Nanomaterials (Basel) ; 14(17)2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39269081

RESUMEN

Cellulose nanofibrils (CNFs) have theoretically ideal properties for bio-based composite applications; however, the incorporation of these materials into polymers is made challenging by the strong binding of water to CNFs and the irreversible agglomeration of CNFs during drying. Previous methods used "contact dewatering", wherein the addition of wood flour (WF) to CNFs facilitated the mechanical removal of water from the system via cold pressing, which showed potential in producing dried CNF fibrils attached to wood fibers for biocomposite applications. In this work, the viability of contact dewatering with poly(lactic) acid (PLA) powder for PLA/CNF composites was evaluated. The energy efficiency of dewatering, preservation of nanoscale CNF morphology, and mechanical properties were examined by mixing wet CNFs with pulverized PLA at various loading levels, pressing water out of the system, and compression molding and shear mixing composites for testing. The most impressive results from this dewatering method were the preservation of micron-to-nanoscale fibers with high aspect ratios in PLA-CNF composites; increased strength and modulus of 1.7% and 4.2%, respectively, compared to neat PLA; equivalent or better properties than spray-dried nanocellulose at similar loading levels; and an 11-194x reduction in drying energy compared to spray-drying CNFs.

3.
Heliyon ; 10(15): e35644, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39170263

RESUMEN

The ever-burgeoning sustainable need for humanity to produce lighter, tougher, and more cost-effective materials has led to the development of biodegradable composites. Ever since their creation, natural fiber-based composites have found themselves ubiquitous. Due to their exceptional performance, Natural fiber-reinforced composites have been predominantly used in several engineering applications. Coconut leaf sheath (CLS) is an abundantly available agro-waste that can be easily extracted from the coconut tree. This review investigates the potential of incorporating coconut sheath into polymeric matrices. Also, the effects of surface treatments, synthetic fiber hybridization, and nanofiller-modified matrices were analyzed in detail. It has been observed that surface modification of coconut sheath, hybridization with other natural or synthetic fibers, and nanofiller-modified polymeric composites exhibit better mechanical performance compared to monolithic coconut sheath-based polymeric composites. One of the key advantages of hybrid composites is that they can combine the strengths of different constituents to overcome their individual limitations. Moreover, coconut sheath-based hybrid composites enhance the composites' damage tolerance and reduce the material cost.

4.
Polymers (Basel) ; 16(15)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39125145

RESUMEN

Materials for low-permittivity and electrical insulation applications need to be re-engineered to achieve sustainable development. To address this challenge, the proposed study focused on the dielectric and mechanical optimization of 3D-printed cellulose-based composites for electrical insulation applications. Two different fillers, microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC), were used to create biocomposites and bionanocomposites, respectively, blended into a polylactic acid (PLA) matrix. The effects of infill ratio, printing temperature, and filler content on dielectric and mechanical properties were measured using an incomplete L9 (3^3) factorial design. The findings showed that the infill ratio was the most significant factor influencing the properties tested, directly attributable to the increase in material availability for polarization and mechanical performance. The second most influential factor was the filler content, increasing the polarity of the tested composites and decreasing the toughness of the biocomposites and bionanocomposites. Finally, printing temperature had no significant effect. Results for the biocomposites at a 50% infill ratio, 200 °C printing temperature, and a weight content of MCC of 15% gave a 60% higher tensile-mode stiffness than neat PLA printed under the same conditions, while exhibiting lower dielectric properties than neat PLA printed with a 100% infill ratio. These results pave the way for new lightweight materials for electrical insulation.

5.
Int J Pharm ; 663: 124541, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39089344

RESUMEN

Although the use of thermoplastic polyurethane (Tpu) nanofiber mats as wound dressings is of great interest due to their mechanical properties, they are hindered by their poor wettability and bioavailability. In this study, we aimed to improve the cellular affinity of Tpu nanofiber mats for skin disorders by incorporating extracted collagen (Col) from tendons and physically mixed with a layer of phytoceramides (Phyto) to produce TpuCol@X-Phyto mats in which the weight % of Phyto relatively to the weight of the solution was X = 0.5, 1.0, or 1.5 wt% via facile electrospinning approach. The collective observations strongly indicate the successful incorporation and retention of Phyto within the TpuCol architecture. An increase in the Phyto concentration decreased the water contact angle from 69.4° ± 3.47° to 57.9° ± 2.89°, demonstrating improvement in the hydrophilicity of Tpu and binary blend TpuCol nanofiber mats. The mechanical property of 1.0 wt% Phyto aligns with practical requirements owing to the presence of two hydroxyl groups and the amide linkage likely contributing to various hydrogen bonds, providing mechanical strength to the channel structure and a degree of rigidity essential for transmitting mechanical stress. The proliferation of human skin fibroblast (HSF) peaked significantly 100 % with TpuCol@X-Phyto mats coated for X =1.0 and 1.5 wt% of Phyto. Electrospun scaffolds with the highest Phyto content have shown the lowest degree of hemolysis, demonstrating the high level of compatibility between them and blood. The TpuCol@1.5Phyto mat also demonstrated higher efficacy in antibacterial and antioxidant activities, achieving a rate of DPPH radical scavenging of 83.3 % for this latter property. The most notable wound closure among all tested formulations was attributed to higher Phyto. Thus, the developed TpuCol@1.5Phyto nanofiber formula exhibited enhanced healing in an in vitro epidermal model.


Asunto(s)
Colágeno , Nanofibras , Poliuretanos , Nanofibras/química , Poliuretanos/química , Humanos , Colágeno/química , Enfermedades de la Piel/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/administración & dosificación , Fibroblastos/efectos de los fármacos , Antibacterianos/química , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Vendajes , Cicatrización de Heridas/efectos de los fármacos , Piel/metabolismo , Piel/efectos de los fármacos , Interacciones Hidrofóbicas e Hidrofílicas
6.
Int J Biol Macromol ; 278(Pt 4): 134695, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39151861

RESUMEN

The growing bioeconomic demand for lightweight, eco-friendly materials with functional versatility and competitive mechanical properties drives the resurgence of cellulose as a sustainable scaffold for various applications. This review comprehensively scrutinizes current progressions in cellulose functional materials (CFMs), concentrating on their structure-property connections. Significant modification methods, including cross-linking, grafting, and oxidation, are discussed together with preparation techniques categorized by cellulose sources. This review article highlights the extensive usage of modified cellulose in various industries, particularly its potential in optical and toughening applications, membrane production, and intelligent bio-based systems. Prominence is located on low-cost procedures for developing biodegradable polymers and the physical-chemical characteristics essential for biomedical applications. Furthermore, the review explores the role of cellulose derivatives in smart packaging films for food quality monitoring and deep probes into cellulose's mechanical, thermal, and structural characteristics. The multifunctional features of cellulose derivatives highlight their worth in evolving environmental and biomedical engineering applications.


Asunto(s)
Materiales Biocompatibles , Celulosa , Celulosa/química , Celulosa/análogos & derivados , Materiales Biocompatibles/química , Embalaje de Alimentos/métodos , Humanos
7.
Adv Sci (Weinh) ; : e2406311, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136053

RESUMEN

Lignin, one of the most abundant biomaterials and a large-scale industrial waste product, is a promising filler for polymers as it reduces the amount of fossil resources and is readily available. 3D printing is well-known for producing detailed polymer structures in small sizes at low waste production. Especially light-assisted 3D printing is a powerful technique for production of high-resolution structures. However, lignin acts as a very efficient absorber for UV and visible light limiting the printability of lignin composites, reducing its potential as a high-volume filler. In this work, the decolorization of lignin is presented for high-resolution 3D printing of biocomposites with lignin content up to 40 wt.%. Organosolv lignin (OSL) is decolorized by an optimized low-energy process of acetylation and subsequent UV irradiation reducing the UV absorbance by 71%. By integration of decolorized lignin into bio-based tetrahydrofurfuryl acrylate (THFA), a lignin content of 40 wt.% and a resolution of 250 µm is achieved. Due to the reinforcing properties of lignin, the stiffness and strength of the material is increased by factors of 15 and 2.3, respectively. This work paves the way for the re-use of a large amount of lignin waste for 3D printing of tough materials at high resolution.

8.
Heliyon ; 10(13): e32668, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39091929

RESUMEN

The Cameroon has two bamboo species indigenous to Africa (the alpine bamboo, Yushina alpina and the savannah bamboo, Oxytenanthera abyssinica), and one largely exotic species, Bambusa vulgaris. However, little on their physical characteristics and strength for the composites materials applications is known for these two indigenous bamboos species in Cameroon. Therefore, in this study, emphasis was laid on the alpine bamboo Y. alpina, to evaluate its potential for biocomposites applications. Y. alpina with ages ranging from 1 to 3 years, 4-5 years, and 7 years were characterized. The mechanical and physical properties of these three age ranges were compared. In the first place, the surface texture of the fibers was examined by scanning electron microscopy. Afterwards, chemical treatment was performed on the fibers with 1 % NaOH. In addition, the chemical bonds of the molecules (functional groups) were identified by Fourier transform infrared spectra (FTIR) and the thermal properties of the fibers were examined with a thermogravimetric analyzer. Furthermore, the fibers density was assessed using the Rilem protocol and a tensile testing machine was used to determine the mechanical properties of the treated fibers with 1 % of NaOH. Finally, a dynamic mechanical analysis of 7-year-old Y. alpina fibers was carry out. The results indicate that the Young's modulus of treated fibers with ages ranging from 1 to 3 years, 4-5 years, and 7 years were around 18 GPa, 10 GPa, and 14 GPa, respectively. In summary, this study underlines two primary points: (1) providing a platform for researchers to better understand the influence of age on the physical and mechanical properties of indigenous bamboo Y. alpina; and (2) providing a platform to validate suitable designs of biocomposites materials with Y. alpina.

9.
J Funct Biomater ; 15(8)2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39194665

RESUMEN

A wide range of applications using functionalized magnetic nanoparticles (MNPs) in biomedical applications, such as in biomedicine as well as in biotechnology, have been extensively expanding over the last years. Their potential is tremendous in delivery and targeting systems due to their advantages in biosubstance binding. By applying magnetic materials-based biomaterials to different organic polymers, highly advanced multifunctional bio-composites with high specificity, efficiency, and optimal bioavailability are designed and implemented in various bio-applications. In modern drug delivery, the importance of a successful therapy depends on the proper targeting of loaded bioactive components to specific sites in the body. MNPs are nanocarrier-based systems that are magnetically guided to specific regions using an external magnetic field. Therefore, MNPs are an excellent tool for different biomedical applications, in the form of imaging agents, sensors, drug delivery targets/vehicles, and diagnostic tools in managing disease therapy. A great contribution was made to improve engineering skills in surgical diagnosis, therapy, and treatment, while the advantages and applicability of MNPs have opened up a large scope of studies. This review highlights MNPs and their synthesis strategies, followed by surface functionalization techniques, which makes them promising magnetic biomaterials in biomedicine, with special emphasis on drug delivery. Mechanism of the delivery system with key factors affecting the drug delivery efficiency using MNPs are discussed, considering their toxicity and limitations as well.

10.
Int J Biol Macromol ; 279(Pt 1): 135092, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39197620

RESUMEN

In a global context marked by food insecurity, it is essential for food science and packaging technology researchers and stakeholders to ensure the availability of safe and adaptable foods with minimal environmental impact. Achieving sustainability in food packaging requires multiple approaches, including the use of natural and biodegradable materials including cellulosic fibers. The current study aimed to develop and characterize and optimized an effective biocomposite food packaging/storing materials, specifically for a popular Ethiopian flatbread called injera, made from a grain called 'Teff' (Eragrostis tef). The proposed biocomposite food storage and packaging was designed by incorporating fiber-reinforcing materials, namely false banana, also called Enset fibers (EFs), and ZnO nanoparticles (ZnO NPs) into a polylactic acid (PLA) matrix. A central composite design (CCD) approach was used to evaluate the impact of the reinforcing Enset fibers (EFs) at 5 %, 15 %, and 25 % and ZnO NPs at 0 %, 5 %, and 10 % levels. The developed functional biocomposite packaging materials were tested and characterized for various properties, including mechanical strength, water activity, antifungal activity, and migration properties. The results showed that the inclusion of ZnO NPs improved the tensile strength, migration, and barrier properties, while the reinforcing fiber enhanced mechanical and migration properties but reduced barrier properties. The combined effect of the reinforcement fibers (EFs) and ZnO NPs led to further improvements in the mechanical strength and migration properties, though no interaction effect was observed on barrier properties. The optimal solution, consisting of 6.7 % ZnO nanoparticles and 6 % Enset fibers, resulted in a highly effective packaging and storage prototype that extended the freshness of the food for over eight days.

11.
Int J Biol Macromol ; 277(Pt 1): 133852, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39025171

RESUMEN

The potential of Hylocereus polyrhizus peel (HPP) as a new eco-friendly reinforcement for thermoplastic sago starch/agar composite (TPSS/agar) was investigated. The integration of HPP into TPSS/agar composite aimed to enhance its mechanical and thermal characteristics. The study employed Fourier transform-infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), Thermogravimetric analysis (TGA), and Differential Scanning Calorimetry (DSC), as well as mechanical, physical properties and soil burial testing to analyse the composites. The results showed a favourable miscibility between the matrix and filler, while at higher concentrations of HPP, the starch granules became more visible. The tensile and impact properties of the composites improved significantly after incorporating HPP at 20 wt%, with values of 12.73 MPa and 1.87 kJ/m2, respectively. The glass transition temperature (Tg) and initial decomposition temperature (Ton) decreased with the addition of HPP. The density of the composites reduced from 1.51 ± 0.01 to 1.26 ± 0.01 g/cm3 as the HPP amount increased. The environmental properties indicated that the composites can be composted, with weight loss accelerating from 35 to 60 % and 61 to 91 % by the addition of HPP in 2- and 4-weeks' time, respectively. The study demonstrates the potential of TPSS/agar/HPP composites as eco-friendly materials for various applications.


Asunto(s)
Agar , Cactaceae , Frutas , Almidón , Agar/química , Almidón/química , Cactaceae/química , Frutas/química , Temperatura , Termogravimetría , Biodegradación Ambiental , Espectroscopía Infrarroja por Transformada de Fourier , Rastreo Diferencial de Calorimetría , Resistencia a la Tracción
12.
Int J Biol Macromol ; 276(Pt 1): 133668, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38992537

RESUMEN

This review explores the intricate wound healing process, emphasizing the critical role of dressing material selection, particularly for chronic wounds with high exudate levels. The aim is to tailor biodegradable dressings for comprehensive healing, focusing on maximizing moisture retention, a vital element for adequate recovery. Researchers are designing advanced wound dressings that enhance techno-functional and bioactive properties, minimizing healing time and ensuring cost-effective care. The study delves into wound dressing materials, highlighting carrageenan biocomposites superior attributes and potential in advancing wound care. Carrageenan's versatility in various biomedical applications demonstrates its potential for tissue repair, bone regeneration, and drug delivery. Ongoing research explores synergistic effects by combining carrageenan with other novel materials, aiming for complete biocompatibility. As innovative solutions emerge, carrageenan-based wound-healing medical devices are poised for global accessibility, addressing challenges associated with the complex wound-healing process. The exceptional physico-mechanical properties of carrageenan make it well-suited for highly exudating wounds, offering a promising avenue to revolutionize wound care through freeze-drying techniques. This thorough approach to evaluating the wound healing effectiveness of carrageenan-based films, particularly emphasizing the development potential of lyophilized films, has the potential to significantly improve the quality of life for patients receiving wound healing treatments.


Asunto(s)
Vendajes , Carragenina , Liofilización , Cicatrización de Heridas , Carragenina/química , Cicatrización de Heridas/efectos de los fármacos , Humanos , Animales , Materiales Biocompatibles/química
13.
Biomimetics (Basel) ; 9(7)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-39056834

RESUMEN

Sponges (phylum Porifera) were among the first metazoans on Earth, and represent a unique global source of highly structured and diverse biosilica that has been formed and tested over more than 800 million years of evolution. Poriferans are recognized as a unique archive of siliceous multiscaled skeletal constructs with superficial micro-ornamentation patterned by biopolymers. In the present study, spicules and skeletal frameworks of selected representatives of sponges in such classes as Demospongiae, Homoscleromorpha, and Hexactinellida were desilicified using 10% HF with the aim of isolating axial filaments, which resemble the shape and size of the original structures. These filaments were unambiguously identified in all specimens under study as F-actin, using the highly specific indicators iFluor™ 594-Phalloidin, iFluor™ 488-Phalloidin, and iFluor™ 350-Phalloidin. The identification of this kind of F-actins, termed for the first time as silactins, as specific pattern drivers in skeletal constructs of sponges opens the way to the fundamental understanding of their skeletogenesis. Examples illustrating the biomimetic potential of sophisticated poriferan biosilica patterned by silactins are presented and discussed.

14.
Biopolymers ; : e23616, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39031485

RESUMEN

Polymer composites are known for its light weight and specific mechanical characteristics. This study examines sodium hydroxide (NaOH)-treated coir fiber, an agro-leftover, stuffed in a polyester matrix with termite frass powder, a bio-leftover for possible use in light-weight structural applications. Composite samples were made using compression molding and NaOH-treated coir fiber reinforced hybrid polymer composite (TCRHPC) with 40 wt% treated coir fiber and 1, 2, 3, and 4 wt% termite frass powder. TCRHPC samples mechanical, water captivation, tribological, and thermal properties were affected by termite frass powder wt%. The TCRHPC sample with 3 wt% termite frass powder has excellent mechanical properties, which improved by tensile (41.6%), flexural (28.57%), impact (43.7%), and hardness (18.84%) properties. With perfect water captivation and low weight increases in normal water (0.017 g), seawater (0.015 g), and NaOH solution (0.010 g), the identical composite sample with thermal stability up to 238°C also reduced wear mass by 5.27%. Conversely, filler agglomeration and heterogeneous dispersion in composite sample impair thermo-mechanical characteristics of TCRHPC containing 4 wt% termite frass powder. The bonding among polyester, treated coir fiber, and termite frass powder in composites were appraised with the aid of fractographic images of TCRHPC samples. The results show that TCRHPC material suits well for support structures requiring lesser weight.

15.
Polymers (Basel) ; 16(14)2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-39065276

RESUMEN

The aim of the presented work was to functionalize a blend based on polyhydroxyalkanoate (PHA): poly(hydroxybutyrate (PHB) with poly(lactic acid) (PLA) and a mixture of three selected herb extracts, namely, Hypericum L., Urtica L. and Chelidonium L., (E), zinc oxide (ZnO) and a combined system (EZnO), produced via extrusion. Before processing with bioresin, the natural modifiers were characterized using thermal analysis, FTIR and antimicrobial tests. The results revealed interactions between the extracts and the filler, leading to higher thermal stability in EZnO than when using E alone. Moreover, the mixture of extracts exhibited antimicrobial properties toward both Gram-negative (S. aureus) as well as Gram-positive bacteria (E. coli). Modified regranulates were transformed into films by cast extrusion. The influence of the additives on thermal (DSC, TGA and OIT), mechanical, barrier (WVTR and OTR), morphological (FTIR) and optical properties was investigated. The EZnO additive had the highest impact on the mechanical, barrier (OTR and WVTR) and optical properties of the bioresin. The microbial test results revealed that PHA-EZnO exhibited higher activity than PHA-ZnO and PHA-E and also reduced the number of S. aureus, E. coli and C. albicans cells. The findings confirmed the synergistic effect between the additive components. Modified polyester films did not eliminate the phi6 bacteriophage particles completely, but they did decrease their number, confirming moderate antiviral effectiveness.

16.
Materials (Basel) ; 17(14)2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39063785

RESUMEN

The growing demand for sustainable materials has significantly increased interest in biocomposites, which are made from renewable raw materials and have excellent mechanical properties. The use of machine learning (ML) can improve our understanding of their mechanical behavior while saving costs and time. In this study, the mechanical behavior of innovative biocomposite sandwich structures under quasi-static out-of-plane compression was investigated using ML algorithms to analyze the effects of geometric variations on load-bearing capacities. A comprehensive dataset of experimental mechanical tests focusing on compression loading was employed, evaluating three ML models-generalized regression neural networks (GRNN), extreme learning machine (ELM), and support vector regression (SVR). Performance indicators such as R-squared (R2), mean absolute error (MAE), and root mean square error (RMSE) were used to compare the models. It was shown that the GRNN model with an RMSE of 0.0301, an MAE of 0.0177, and R2 of 0.9999 in the training dataset, and an RMSE of 0.0874, MAE of 0.0489, and R2 of 0.9993 in the testing set had a higher predictive accuracy. In contrast, the ELM model showed moderate performance, while the SVR model had the lowest accuracy with RMSE, MAE, and R2 values of 0.5769, 0.3782, and 0.9700 for training, and RMSE, MAE, and R2 values of 0.5980, 0.3976 and 0.9695 for testing, suggesting that it has limited effectiveness in predicting the mechanical behavior of the biocomposite structures. The nonlinear load-displacement behavior, including critical peaks and fluctuations, was effectively captured by the GRNN model for both the training and test datasets. The progressive improvement in model performance from SVR to ELM to GRNN was illustrated, highlighting the increasing complexity and capability of machine learning models in capturing detailed nonlinear relationships. The superior performance and generalization ability of the GRNN model were confirmed by the Taylor diagram and Williams plot, with the majority of testing samples falling within the applicability domain, indicating strong generalization to new, unseen data. The results demonstrate the potential of using advanced ML models to accurately predict the mechanical behavior of biocomposites, enabling more efficient and cost-effective development and optimization processes in the field of sustainable materials.

17.
Polymers (Basel) ; 16(13)2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-39000624

RESUMEN

Biopolymers from renewable materials are promising alternatives to the traditional petroleum-based plastics used today, although they face limitations in terms of performance and processability. Natural fillers have been identified as a strategic route to create sustainable composites, and natural fillers in the form of waste by-products have received particular attention. Consequently, the primary focus of this article is to offer a broad overview of recent breakthroughs in environmentally friendly Polhydroxyalkanoate (PHA) polymers and their composites. PHAs are aliphatic polyesters obtained by bacterial fermentation of sugars and fatty acids and are considered to play a key role in addressing sustainability challenges to replace traditional plastics in various industrial sectors. Moreover, the article examines the potential of biodegradable polymers and polymer composites, with a specific emphasis on natural composite materials, current trends, and future market prospects. Increased environmental concerns are driving discussions on the importance of integrating biodegradable materials with natural fillers in our daily use, emphasizing the need for clear frameworks and economic incentives to support the use of these materials. Finally, it highlights the indispensable need for ongoing research and development efforts to address environmental challenges in the polymer sector, reflecting a growing interest in sustainable materials across all industries.

18.
Sci Total Environ ; 948: 174474, 2024 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-38964407

RESUMEN

The current demand for composites reinforced with renewable fibers is greater than it has ever been. In comparison to glass fibers, natural fibers yield the advantages of lesser density and cost. Although comparable specific properties exist between glass and natural fibers, the latter shows lower strength. However, with the copper coating and chemical treatment of natural fibers, the strength of the composites can be increased nowadays. The current research investigation focuses on the life cycle assessment of the raw, chemically treated, and copper coated fiber reinforced bagasse and banana composites to compare the emissions on the environment of these samples to prove their applicability. The study includes all the processes, from the extraction of fibers to the formation of composites, i.e., from cradle to gate, and detailed inventory. The ReCiPe H midpoint method has been utilized in SimaPro software to quantify the emissions. The results indicate that the maximum global warming emission is due to the energy consumption used during the manufacturing of these composites. Electricity contribution for chemically treated and copper coated composites in global warming contribution is slightly greater than that of raw composites i.e., 73.275 % in C- BG/P, 73.06 % in Cu- BG/P, 73.65 % in C- BN/P and 74.28 % in Cu- BN/P which is comparatively higher than 63.8 % in R- BG/P and 64.97 % in R- BN/P. The next major contributions come from polylactic acid for all the three samples of bagasse fiber reinforced PLA composite and banana fiber reinforced PLA composite. The raw samples also show improved fiber strength compared to chemical and copper coated samples.

19.
Materials (Basel) ; 17(12)2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38930325

RESUMEN

This study involved the optimization of the molded pieces manufacturing process from a poly-3-hydroxybutyrate-co-3-hydroxyvalerate biocomposite containing 30% wood flour by mass. The amount of wood flour and preliminary processing parameters were determined on the basis of preliminary tests. The aim of the optimization was to find the configuration of important parameters of the injection process to obtain molded pieces of good quality, in terms of aesthetics, dimensions, and mechanical properties. The products tested for quality were dog bone specimens. The biocomposite was produced using a single-screw extruder, whereas molded pieces were made using an injection molding process. The Taguchi method was applied to optimize the injection molding parameters, which determine the products quality. Control factors were selected at three levels. The L27 orthogonal plan was used. For each set of input parameters from this plan, four processing tests were performed. The sample weight, shrinkage, elongation at break, tensile strength, and Young's modulus were selected to assess the quality of the molded parts. As a result of the research, the processing parameters of the tested biocomposite were determined, enabling the production of good-quality molded pieces. No common parameter configuration was found for different optimization criteria. Further research should focus on finding a different range of technological parameters. At the same time, it was found that the range of processing parameters of the produced biocomposite, especially processing temperature, made it possible to use it in the Wood Polymer Composites segment.

20.
Materials (Basel) ; 17(12)2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38930326

RESUMEN

The main goal of this study is the comparison of different reinforcement architectures on the low-velocity impact behavior of green composites. The study includes the comparison of unidirectional, basket weave, and twill weave flax/PLA composites, they are subjected to unidirectional tensile tests, drop-weight impact tests, and after-impact compression tests. Results show that the unidirectional composite demonstrates superior tensile strength and initial modulus due to reduced fiber crimp, while basket weave exhibits the highest energy absorption capability and strain capacity attributed to its higher fiber-weight ratio and fiber crimp. Unidirectional composite also shows a larger impacted damage area compared to basket weave and twill weave, attributed to its internal architecture. Residual compressive strength across all composites decreased by 40% compared to the reference sample. However, the reduction in stiffness after impact was different, UD/PLA composite stiffness was reduced by 30% while the reduction in BW/PLA and T/PLA composites was about 20%.

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