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1.
Int J Mol Sci ; 23(11)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35683017

RESUMO

Materials that exhibit highly nonlinear behaviour are intricate to study. This is due to their physical properties, as they possess a very large deformation. Silicone rubber is among the materials that can be classified as possessing such characteristics, despite their being soft and frequently applied in medical applications. Due to their low mechanical properties, however, it is believed that a filler addition could enhance them. This study, therefore, aims to investigate the effect of the addition of bamboo cellulosic filler to silicone rubber in terms of its compressive properties in order to quantify its material constants using the hyperelastic theory, specifically the Neo-Hookean and Mooney-Rivlin models. The specimens' compressive properties were also compared between specimens immersed in seawater and those not immersed in seawater. The findings showed that the compressive properties, stiffness, and compressive strength of the bamboo cellulosic fibre reinforced the silicone rubber biocomposites, improved with higher bamboo filler addition. Specimens immersed in seawater showed that they can withstand a compressive load of up to 83.16 kPa in comparison to specimens not immersed in seawater (up to 79.8 kPa). Using the hyperelastic constitutive models, the Mooney-Rivlin model displayed the most accurate performance curve fit with the experimental compression data with an R2 of up to 0.9999. The material constant values also revealed that the specimens immersed in seawater improved in stiffness property, as the C1 material constant values are higher than for the specimens not immersed in seawater. From these findings, this study has shown that bamboo cellulosic filler added into silicone rubber enhances the material's compressive properties and that the rubber further improves with immersion in seawater. Thus, these findings contribute significantly towards knowledge of bamboo cellulosic fibre-reinforced silicone rubber biocomposite materials.


Assuntos
Elastômeros de Silicone , Força Compressiva , Estresse Mecânico
2.
J Food Sci Technol ; 53(1): 326-36, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26787952

RESUMO

In this study, sugar palm starch (SPS) films were developed using glycerol (G), sorbitol (S) or their combination (GS) as plasticizers at the ratio of 15, 30 and 45 (wt)% using casting technique. The addition of plasticizers to SPS film-forming solutions helped to overcome the brittle and fragile nature of unplasticized SPS films. Increased plasticizer concentration resulted to an increase in film thickness, moisture content and solubility. On the contrary, density and water absorption of plasticized films decreased with increasing plasticizer concentration. Raising the plasticizer content from 15 to 45 % showed less effect on the moisture content and water absorption of S-plasticized films. Films containing glycerol and glycerol-sorbitol plasticizer (G, and GS) demonstrated higher moisture content, solubility and water absorption capacity compared to S-plasticized films. The results obtained in this study showed that plasticizer type and concentration significantly improves film properties and enhances their suitability for food packaging applications.

3.
J Food Sci Technol ; 52(10): 6445-54, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26396389

RESUMO

Biobased food packaging materials are gaining more attention owing to their intrinsic biodegradable nature and renewability. Selection of suitable biobased polymers for food packaging applications could be a tedious task with potential mistakes in choosing the best materials. In this paper, an expert system was developed using Exsys Corvid software to select suitable biobased polymer materials for packaging fruits, dry food and dairy products. If - Then rule based system was utilized to accomplish the material selection process whereas a score system was formulated to facilitate the ranking of selected materials. The expert system selected materials that satisfied all constraints and selection results were presented in suitability sequence depending on their scores. The expert system selected polylactic acid (PLA) as the most suitable material.

4.
Int J Biol Macromol ; 278(Pt 3): 134421, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39227276

RESUMO

In this study, significant improvements in mechanical properties have been seen through the efficient inclusion of Oil Palm Cellulose Nanofibrils (CNF) as nano-fillers into green polymer matrices produced from biomass with a 28 % carbon content. The goal of the research was to make green epoxy nanocomposites utilizing solution blending process with acetone as the solvent with the different CNF loadings (0.1, 0.25, and 0.5 wt%). An ultrasonic bath was used in conjunction with mechanical stirring to guarantee that CNF was effectively dispersed throughout the green epoxy. The resultant nanocomposites underwent thorough evaluation, comparing them to unfilled green epoxy and evaluating their morphological, mechanical, and thermal behavior using a variety of instruments. Field-emission scanning electron microscopy (FE-SEM) was used to validate findings, which showed that the CNF were dispersed optimally inside the nanocomposites. The thermal degradation temperature (Td) of the nanocomposites showed a marginal decrement of 0.8 % in temperatures (from 348 °C to 345 °C), between unfilled green epoxy (neat) and 0.1 wt% of CNF loading. The mechanical test results, which showed a 13.3 % improvement in hardness and a 6.45 % rise in tensile strength when compared to unfilled green epoxy, were in line with previously published research. Overall, the outcomes showed that green nanocomposites have significantly improved in performance.


Assuntos
Celulose , Nanocompostos , Nanofibras , Nanocompostos/química , Celulose/química , Nanofibras/química , Temperatura , Resinas Epóxi/química , Resistência à Tração , Química Verde/métodos , Óleo de Palmeira/química , Fenômenos Mecânicos
5.
Int J Biol Macromol ; 269(Pt 1): 132052, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704068

RESUMO

Researchers are now focusing on using the circular economy model to manufacture nanocellulose composites due to growing environmental issues related to waste management. The circular economy model offers a sustainable solution to the problem by optimizing resource efficiency and waste management by reducing waste, maintaining value over time, minimizing the use of primary resources, and creating closed loops for goods, components, and materials. With the use of the circular economy model, waste, such as industrial, agricultural, and textile waste, is used again to produce new products, which can solve waste management issues and improve resource efficiency. In order to encourage the use of circular economy ideas with a specific focus on nanocellulose composites, this review examines the concept of using circular economy, and explores ways to make nanocellulose composites from different types of waste, such as industrial, agricultural, and textile waste. Furthermore, this review investigates the application of nanocellulose composites across multiple industries. In addition, this review provides researchers useful insights of how circular economics can be applied to the development of nanocellulose composites, which have the goal of creating a flexible and environmentally friendly material that can address waste management issues and optimize resource efficiency.


Assuntos
Celulose , Celulose/química , Gerenciamento de Resíduos/métodos , Gerenciamento de Resíduos/economia , Nanocompostos/química , Nanoestruturas/química , Agricultura/economia , Agricultura/métodos
6.
Int J Biol Macromol ; 268(Pt 1): 131845, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38677695

RESUMO

Researchers have begun focusing on developing biodegradable materials, such as natural fiber/polymer composites (NFPC), since the growing of environmental concerns related to waste management. One crucial aspect that must be established in the development of these composites is their water-absorption behavior. This paper examines the water absorption (WA) behavior of NFPC, with a specific emphasis on natural fiber/polylactic acid (PLA) composites. It discusses processes and numerous aspects related to this behavior, based on recent published research. This review analyzes the influence of several factors, such as the loading of natural fiber, the combination of different natural fibers, the methods used in manufacturing, and the temperature of the water, on the WA behavior of natural fiber/PLA composites. It also explores how WA affects the properties of these composites. In addition, this review also presented techniques for improving the WA resistance of the composites. This review paper provides researchers with insights into the WA behavior of the composites, aiming to facilitate the development of a versatile and eco-friendly material that may effectively address waste disposal challenges.


Assuntos
Poliésteres , Água , Poliésteres/química , Água/química , Temperatura , Absorção Fisico-Química
7.
Int J Biol Macromol ; 255: 128121, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37984579

RESUMO

Material is an inseparable entity for humans to serve different purposes. However, synthetic polymers represent a major category of anthropogenic pollutants with detrimental impacts on natural ecosystems. This escalating environmental issue is characterized by the accumulation of non-biodegradable plastic materials, which pose serious threats to the health of our planet's ecosystem. Cellulose is becoming a focal point for many researchers due to its high availability. It has been used to serve various purposes. Recent scientific advancements have unveiled innovative prospects for the utilization of nanocellulose within the area of advanced science. This comprehensive review investigates deeply into the field of nanocellulose, explaining the methodologies employed in separating nanocellulose from cellulose. It also explains upon two intricately examined applications that emphasize the pivotal role of nanocellulose in nanocomposites. The initial instance pertains to the automotive sector, encompassing cutting-edge applications in electric vehicle (EV) batteries, while the second exemplifies the use of nanocellulose in the field of biomedical applications like otorhinolaryngology, ophthalmology, and wound dressing. This review aims to provide comprehensive information starting from the definitions, identifying the sources of the nanocellulose and its extraction, and ending with the recent applications in the emerging field such as energy storage and biomedical applications.


Assuntos
Ecossistema , Nanocompostos , Humanos , Celulose , Polímeros
8.
RSC Adv ; 14(40): 29624-29635, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39297036

RESUMO

Developing a simple and environmentally friendly method to vary the physical, mechanical, and thermal properties of cellulose films is of great importance. This study aimed to characterize 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO)-oxidized bacterial cellulose (BC) films prepared using non-pressurized hot water vapor (NPHWV) method. A wet BC-pellicle that had been oxidized with TEMPO was treated with NPHWV for 60, 120, and 240 minutes, respectively. As a control, a TEMPO-oxidized BC (TOBC) film without NPHWV was prepared. The results show that the longer NPHWV duration of the TOBC film increased the tensile and thermal properties. This film became more hydrophobic and showed lower moisture absorption, thermal conductivity and organic solvent uptake, more crystalline structure, and higher fiber density after NPHWV treatment. The acquired results provide a simple, inexpensive, and ecologically friendly method for varying TOBC film properties.

9.
Int J Biol Macromol ; 278(Pt 4): 135207, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39256123

RESUMO

The escalating need for a sustainable future has driven the advancement of renewable functional materials. Nanocellulose, derived from the abundant natural biopolymer cellulose, demonstrates noteworthy characteristics, including high surface area, crystallinity, mechanical strength, and modifiable chemistry. When combined with two-dimensional (2D) graphitic materials, nanocellulose can generate sophisticated hybrid materials with diverse applications as building blocks, carriers, scaffolds, and reinforcing constituents. This review highlights the progress of research on advanced functional materials based on the integration of nanocellulose, a versatile biopolymer with tailorable properties, and MXenes, a new class of 2D transition metal carbides/nitrides known for their excellent conductivity, mechanical strength, and large surface area. By addressing the challenges and envisioning future prospects, this review underscores the burgeoning opportunities inherent in MXene/nanocellulose composites, heralding a sustainable frontier in the field of materials science.


Assuntos
Celulose , Celulose/química , Nanoestruturas/química
10.
Polymers (Basel) ; 15(9)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37177374

RESUMO

This study examines the effects of alkaline treatment on the mechanical and thermal properties of miswak fiber-reinforced polylactic acid. The treatment was performed with three distinct concentrations of sodium hydroxide (NaOH): 1 wt %, 2 wt %, and 3 wt %. The difficulties of interaction between the surface of the fiber and the matrix, which led to this treatment, is caused by miswak fiber's hydrophilic character, which impedes its ability to bind with hydrophobic polylactic acid. FTIR, tensile, TGA, and DMA measurements were used to characterize the composite samples. A scanning electron microscope (SEM) was used to examine the microstructures of many broken samples. The treatment is not yet especially effective in enhancing interfacial bonding, as seen by the uneven tensile strength data. The effect of the treated fiber surface significantly improves the tensile strength of miswak fiber-reinforced PLA composites. Tensile strength improves by 18.01%, 6.48%, and 14.50%, respectively, for 1 wt %, 2 wt %, and 3 wt %. Only 2 wt %-treated fiber exhibits an increase of 0.7% in tensile modulus. The modulus decreases by 4.15 % at 1 wt % and by 19.7% at 3 wt %, respectively. The TGA curve for alkali-treated fiber composites demonstrates a slight increase in thermal stability when compared to untreated fiber composites at high temperatures. For DMA, the composites with surface treatment have higher storage moduli than the composite with untreated miswak fiber, especially for the PLA reinforced with 2 wt % alkali miswak fiber, proving the effectiveness of the treatment.

11.
Int J Biol Macromol ; 253(Pt 5): 127119, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37776930

RESUMO

Kenaf fiber has recently garnered exponential interest as reinforcement in composite materials across diverse industries owing to its superior mechanical attributes, ease of manufacture, and inherent biodegradability. In the discourse of this review, various methods of manufacturing kenaf/Polylactic acid (PLA) composites have been discussed meticulously, as delineated in recently published scientific literatures. This paper delves into the chemical modification of kenaf fiber, examining its consequential impact on tensile strength and thermal stability of the kenaf/PLA composites. Further, this review illuminates the role of innovative 3D printing techniques and fiber orientation in augmenting the mechanical robustness of the kenaf/PLA composites. Simultaneously, recent insightful explorations into the acoustic properties of the kenaf/PLA composites, underscoring their potential as sustainable alternative to conventional materials have been reviewed. Serving as a comprehensive repository of knowledge, this review paper holds immense value for researchers aiming to utilize the capabilities of kenaf fiber reinforced PLA composites.


Assuntos
Hibiscus , Indústrias , Estruturas Vegetais , Poliésteres
12.
Heliyon ; 9(4): e15153, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37095902

RESUMO

This paper documents the thermal and biodegradation behaviour of kenaf/cornhusk fiber reinforced corn starch-based hybrid composites film (CS/K-CH) produced by solution casting method. To develop both components as biodegradable hybrid composite, this research used corn starch as matrix, kenaf fiber and cornhusk fibre as a filler. Changes in physical structure and weight from the soil burial test were measured using Mettler Toledo digital balance ME. Films produced from physically blended corn starch reinforced kenaf biocomposites films (CS/K) biocomposite film had faster biodegradation and lost 96.18% of weight within 10 days compared with corn starch hybrid composites that only lost 83.82% of total weight. It was observed that the control film, CS/K biocomposite film was completely degraded after 10 days, meanwhile it took 12 days for hybrid composite films to be fully degrade. The thermal properties such as TGA and DTG were also measured. Addition of corn husk fiber significantly improve the film's thermal properties. Glass transition temperatures of corn starch hybrid films were significantly lowered when cornhusk compositions were increased from 0.2% wt to 0.8% wt. Importantly, the current work has demonstrated that hybrid films made of corn starch can be a suitable biodegradable material for substitute synthetic plastic.

13.
Polymers (Basel) ; 15(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36771944

RESUMO

Developing a conductive cellulose film without any metal compounds remains challenging, though in great demand. However, cellulose film prepared from bacterial cellulose (BC) powder without any metal compounds has poor tensile, physical, and electrical properties, thus limiting its application. Herein, this study aims to prepare and characterize an all-cellulose film from 2,2,6,6-Tetramethylpiperidin-1-yl)oxyl (TEMPO)-oxidized bacterial cellulose (TOBC) powders without adding metal compounds and treated by ultrasonication. TOBC powders are sonicated with various powers of 250, 500, and 750 W for 20 min without any other substance. It was proved that increasing the ultrasonication power level resulted in a significant improvement in the properties of the film. The ultrasonication of 750 W increased tensile strength by 85%, toughness by 308%, light transmittance by 542%, and electrical conductivity by 174% compared to the nonsonicated film. A light-emitting diode connected to a power source through this sonicated film was much brighter than that connected via a nonsonicated film. For the first time, this study reports the preparation of electrically conductive, transparent, strong, and bendable pure TOBC films by increasing ultrasonic power for environmentally friendly electronic devices application.

14.
Polymers (Basel) ; 14(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36145924

RESUMO

Bio and Synthetic Based Polymer Composite Materials is a newly opened Special Issue of Polymers, which aims to publish original and review papers on new scientific and applied research and make contributions to the findings and understanding of the reinforcing effects of various bio and synthetic-based polymers on the performance of polymer composites [...].

15.
Polymers (Basel) ; 14(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36080552

RESUMO

Current Progress in Biopolymer-Based Bionanocomposites and Hybrid Materials is a newly opened Special Issue of Polymers, which aims to publish original and review papers on the new scientific and applied research and make boundless contributions to the findings and understanding of the reinforcing effects of various synthetic and natural fibres on the performance of biopolymer composites [...].

16.
Int J Biol Macromol ; 213: 1-10, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35594940

RESUMO

Using the solution casting method, a novel biodegradable thermoplastic arrowroot (Maranta arundinacea) starch (TPAS) films containing arrowroot fiber (AF) at different concentrations (0, 2, 4, 6, 8, and 10 wt%) were developed and characterized in terms of thermal, antibacterial activity, water vapor permeability (WVP), biodegradability, and light transmittance properties. The TPAS/AF-10 biocomposite film revealed a higher degradation temperature (313.02 °C) than other biocomposite films, indicating better thermal stability. Furthermore, increasing AF concentration led to a significant (p < 0.05) reduction in the linear burning rate and WVP of the biocomposite films from 248.9 to 115.2 mm/min and 8.18 × 10-10 ×g. s-1.m-1. Pa-1 to 5.20 × 10-10 ×g. s-1.m-1. Pa-1, respectively. The addition of fibers in the surface structure had a significant impact on remarkable drop in opacity (91.1 to 74.1%). In addition, the incorporation of AF and control film showed an insignificant effect against three pathogenic bacteria, including Staphylococcus aureus (ATCC 43300), Escherichia coli (ATCC 25922), and Bacillus subtilis (B29). The soil burial findings demonstrated that the weight loss of TPAS/AF biocomposite films was significantly higher than TPAS film. Overall, the reinforcement of arrowroot fiber with TPAS film improved the properties of biocomposites for environmentally friendly food packaging applications.


Assuntos
Anti-Infecciosos , Marantaceae , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Fibras na Dieta , Grão Comestível , Embalagem de Alimentos , Marantaceae/química , Amido/química , Vapor
17.
Polymers (Basel) ; 14(8)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35458339

RESUMO

Biocomposite films were prepared using corn starch (CS), sorbitol as a plasticiser, and multi-scale kenaf fibre as reinforcing filler. The microstructure and the physical, tensile, and water barrier properties of corn starch reinforced with kenaf fibre were characterised and investigated. The biocomposite films were developed via the solution casting technique using 10 g of CS with 0 to 8% kenaf fibre as filler treated with 30% (w/w, starch basis) of sorbitol. The increased amount of kenaf fibre introduced contributed to improvements in film thickness, weight, and density. Conversely, slight reductions in the biocomposite films' moisture content, water absorption, and solubility rating were 9.86-5.88%, 163.13-114.68%, and 38.98-25.17%, respectively. An X-ray diffraction (XRD) test revealed that the films were amorphous and that there was no effect on the crystallinity structure of films with kenaf fibre reinforcement. Fourier transform infrared (FT-IR) and rheological analysis indicated that kenaf fibre could weaken the molecular interaction of the film matrix. Field emission scanning electron microscope (FESEM) revealed the arrangement and uniform distribution of kenaf fibre at 0.2-0.8%. The incorporation of kenaf increased the tensile strength, Young's modulus, and elongation at break until (6% wt) of fibre. With the kenaf fibre incorporation, the optimal tensile strength, Young's modulus, and elongation at break of the films reached 17.74 MPa, 1324.74 MPa, and 48.79%, respectively. Overall, the introduction of kenaf fibre as filler enhanced the physical and mechanical properties of CS films.

18.
Polymers (Basel) ; 14(3)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35160378

RESUMO

This research is driven by stringent environmental legislation requiring the consumption and use of environmentally friendly materials. In this context, this paper is concerned with the development and characterization of thermoplastic arrowroot starch (TPAS) based biocomposite films by incorporating arrowroot fiber (AF) (0-10%) into a glycerol plasticized matrix by using the solution casting method. Developed TPAS/AF composite films were investigated, such as physical, morphological (FESEM), tensile, and tear strength characteristics. The tensile and tear strengths of TPAS/AF composites were increased significantly from 4.77 to 15.22 MPa and 0.87 to 1.28 MPa, respectively, as compared to the control TPAS films, which were 2.42 MPa and 0.83 MPa, respectively, while elongation was significantly decreased from 25.57 to 6.21% compared to control TPAS film, which was 46.62%. The findings revealed that after the fiber was reinforced, the mechanical properties were enhanced, and the optimum filler content was 10%. Regardless of fiber loadings, the results of water absorption testing revealed that the composite films immersed in seawater and rainwater absorbed more water than distilled water. Overall, the results of this research focus on providing information on biopolymer composite film and revealing the great potential it has for the food packaging industry.

19.
Sci Total Environ ; 803: 149911, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34525745

RESUMO

COVID-19 global pandemic, originated from Wuhan, resulted in a massive increase in the output of polypropylene (PP)-based personal protective equipment (PPE) for healthcare workers. The continuous demand of PPE across the world caused the PP based plastic wastes accumulation. Some alternative approaches that have been practiced apart from collecting the plastic waste in the landfills are incineration approach and open burning. However, there were many drawbacks of these practices, which promote the release of chemical additives and greenhouse gases into the environment. Therefore, a proper approach in treating the plastic wastes, which introduces conversion of plastic wastes into renewable energy is paramount. Along the way of extensive research and studies, the recovery of PP plastic to fuel-like liquid oil and solid char through thermal decomposition of pyrolysis process, helps in reducing the number of PP plastic wastes and produces good quality pyrolysis liquid oil and solid char to be used in fuel applications. This paper summarizes the pyrolysis process for massively produced PP plastic wastes, type of pyrolysis used and the main pyrolysis parameters affecting the product yields. Literature studies of pyrolysis of PP plastic and several key points to optimize solid char production for PP were thoroughly elaborated in this review paper.


Assuntos
COVID-19 , Gerenciamento de Resíduos , Humanos , Pandemias , Plásticos , Polipropilenos , Pirólise , SARS-CoV-2
20.
Polymers (Basel) ; 15(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36616412

RESUMO

Biocomposite materials are essential for environmental protection, as they have the ability of substituting synthetic plastic with natural materials. This work investigated how different plasticizers (Glycerol (G), Fructose (F), Sorbitol (S), and Urea (U)) affect the morphological, mechanical, thermal, and physical characteristics of films made of wheat starch at various concentrations (0%, 15%, 25%, and 35%). Plasticizers were added to improve the flexibility and homogeneity of the wheat starch-based bioplastic. Control film exhibited high tensile strength (38.7 MPa) with low elongation (1.9%). However, films plasticized with 35% sorbitol showed the highest elongation, which was 60.7% at break. At 35% of all plasticizers, fructose showed the highest tensile strength, with 7.6 MPa. The addition of different plasticizers shows improvement in water resistance; films plasticized with glycerol had the lowest water absorption at 35% fructose (187.4%) and also showed coherent surfaces. Glycerol, sorbitol, and urea films showed a higher mass loss compared to fructose films. Fructose showed the highest performance after the analysis of the results, with low water absorption, water content, and mass loss and with high mechanical performance at 35% of fructose. SEM images show that the addition of fructose and glycerol improves the surface homogenate, while sorbitol and urea have a less compact structure with large pores.

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