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1.
Int J Biol Macromol ; : 135855, 2024 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-39317277

RESUMO

To develop technology more applicable to industrial settings, this study aimed to produce agar-based bioplastic films using extrusion followed by hot compression. The research examined various amounts of glycerol incorporation as the plasticizer, which also facilitated the flowability of the extrusion process. These variations included agar-glycerol ratios of 75:25, 70:30, 65:35, 60:40, and 55:45 (% w/w). Moreover, the films underwent thorough testing to assess their physical, mechanical, chemical, water sensitivity, surface imaging, and biodegradability properties. The results showed that increasing the amount of glycerol in the agar film matrix generally made the films more sensitive to water, resulting in greater hydrophilicity. This change was primarily owing to the increased presence of hydroxyl groups. It also affected other characteristics, such as enhancing the film's stretchability and thermal stability. Furthermore, a decrease in film density was observed, leading to reduced tensile strength and barrier properties. Moreover, the higher glycerol content improved its surface wettability and the higher agar content accelerated the film's biodegradability rate. Microstructural examination using scanning electron microscopy and chemical analysis (FTIR) revealed a homogeneous mixture of agar and glycerol produced through the extrusion process. These findings demonstrate the potential of extrusion techniques for the large-scale production of agar-based bioplastics.

2.
Int J Biol Macromol ; 279(Pt 1): 135093, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39197627

RESUMO

The hybrid composite sample based on Prosopis Juliflora (PJ) bark and ramie fibre with different length, weight percentage, and curing temperature were created for the first time in this work. Totally, 120 hybrid composite samples were tested in this study. There were five different fibre lengths: 10 mm, 15 mm, 20 mm, 25 mm, and 30 mm, weight percentages 10 %, 20 %, 30 %, 40 %, and 50 %, and different curing temperatures 80 °C, 90 °C, 100 °C, 110 °C, and 120 °C used to produce the hybrid composite samples. Due to the cross-linking ability with the epoxy matrix, the hybrid composite specimen shows high resistance up to 98 Shore D hardness. The high polarity of the epoxy matrix and the hydrogen bond strengthening effect, increased the composite sample flexural strength by 12 %. The curing temperature of 100 °C, 20 mm fibre length, and 30 % of the hybrid composite sample achieved the highest tensile strength (28.76 MPa), flexural strength (46.54 MPa), impact strength (4.5 J), and hardness strength properties (98 shore D). Thermo gravimetric analysis (TGA) revealed the composite samples initial decomposition temperature (Ti) at 98 °C, maximum decomposition temperature (Tmax) at 320 °C, and the final decomposition temperature (Tf) at 466 °C.

3.
Int J Biol Macromol ; 271(Pt 1): 132569, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38797303

RESUMO

Food packaging based on natural polymers from polysaccharides and proteins can be an alternative to replace conventional plastics. In the present study, semi-refined iota carrageenan (SRIC) and fish gelatin (FG) were used as polymer matrix film with different concentration ratios (0.5:1.5 %, 1.0:1.0 % and 1.5:0.5 % w/w) and SiO2-ZnO nanoparticles were incorporated as fillers with the same concentration in all formulas (0.5:1.5 % w/w carrageenan-fish gelatin). This study aimed to develop films for food packaging applications with desirable physical, mechanical, optical, chemical, and microbiological properties. The results showed that incorporating SiO2-ZnO nanoparticles significantly (p < 0.05) improved the films' elongation at break, UV-screening properties, and antimicrobial activity. Also, the films' thickness, degradability, and transparency significantly (p < 0.05) increased with the higher concentration of fish gelatin addition in the SRIC matrix polymer. The best formula was obtained on the SRIC-FG film at the ratio of 1.5:0.5 % w/w, which performed excellent antimicrobial activity. Thus, semi-refined iota carrageenan/fish gelatin-based biocomposite film incorporated with SiO2-ZnO nanoparticles can be potentially developed as eco-friendly and intelligent food packaging materials to resolve traditional plastic-related issues and prevent food waste.


Assuntos
Carragenina , Embalagem de Alimentos , Gelatina , Nanopartículas , Dióxido de Silício , Óxido de Zinco , Carragenina/química , Gelatina/química , Óxido de Zinco/química , Dióxido de Silício/química , Nanopartículas/química , Embalagem de Alimentos/métodos , Animais , Peixes , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia
4.
Int J Biol Macromol ; 239: 124082, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36965566

RESUMO

This study concerns a scoping and literature review of nanocarbon and its composites with details on specific propositions, including nanocarbon history, nanocarbon types, and lignocellulose nanocarbon types, properties, applications, toxicity, regulation, and business model for commercialization. The review brings novelties, comprehensively expounding on laboratory studies and industrial applications of biomass or lignocellulose materials-derived nanocarbon and its composites. Since its first discovery in the form of Buckyball in 1985, nanocarbon has brought interest to scientists and industries for applications. From the previous studies, it is discovered that many types of nanocarbon are sourced from lignocellulose materials. With their excellent properties of nanomaterials, nanocarbon has been harnessed for such as reinforcing and filler agents for nanocomposites or direct use of individual nanocarbon for specific purposes. However, the toxicological properties of nanocarbon have delivered a level of concern in its use and application. In addition, with the radically growing increase in the use of nanocarbon, policies have been enacted in several countries that rule on the use of nanocarbon. The business model for the commercialization of lignocellulose-based nanocarbon was also proposed in this study. This study can showcase the importance of both individual nanocarbon and nanocarbon-based composites for industrial implementations by considering their synthesis, properties, application, country legislations/regulations, and business model. The studies also can be the major references for researchers to partner with industries and governments in investing in lignocellulose-sourced nanocarbon potential research, development, and policies.


Assuntos
Lignina , Nanocompostos
5.
Environ Res ; 212(Pt D): 113235, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35500851

RESUMO

Indonesia has committed to restoring degraded peatlands by revegetating them with paddy plants using paludiculture systems. Nanofertilizers derived from chitosan and oil palm biomass can be used to enhance paddy growth. This study analyzed the potential growth media of chitosan nanocomposite films for paddy seeds grown in tropical peatland. Chitosan nanocomposites were synthesized by reinforcing chitosan with activated carbon nanoparticles (ACNPs), nonactivated carbon nanoparticles (n-ACNPs), and lignocellulose nanofibers (LCNFs). All carbon nanoparticles were reversibly aggregated, whereas LCNFs did not have a tendency to aggregate but were entangled. The highest specific surface area and pore volume are on EFB ACNPs, followed by OPT LCNFs and EFB n-ACNPs. Both nanocomposites' tensile strength and elastic modulus value were reduced with an average of 45.77% and 34.00%, respectively, because of the lack of nano- and micro-aggregates formation, good dispersion, and incompatibility. In a germination test, chitosan nanocomposites provided the best growth patterns for the Dendang paddy variety, whereas, in a greenhouse test, the nanocomposites had the best growth patterns for the Indragiri paddy variety. Chitosan/empty fruit bunch ACNP nanocomposites grown in a germinator had the highest growth normality (100.00%), highest maximum growth potential (100.00%), and highest height average (11.27 cm). In the greenhouse test, chitosan/oil palm trunk n-ACNPs achieved the highest growth natality (16.44%) and growth rate (65.74%). All chitosan nanocomposites had a synergetic biofertilizing effect on fungi and mycorrhiza. Chitosan nanocomposites can be used as a growth regulator for peatland paddy varieties and can accelerate peatland restoration in tropical areas.


Assuntos
Quitosana , Nanocompostos , Nanofibras , Nanopartículas , Lignina , Sementes
6.
Int J Biol Macromol ; 200: 303-326, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34999045

RESUMO

Each year, 50 to 70 million tonnes of lignin are produced worldwide as by-products from pulp industries and biorefineries through numerous processes. Nevertheless, about 98% of lignin is directly burnt to produce steam to generate energy for the pulp mills and only a handful of isolated lignin is used as a raw material for the chemical conversion and for the preparation of various substances as well as modification of lignin into nanomaterials. Thus, thanks to its complex structure, the conversion of lignin to nanolignin, attracting growing attention and generating considerable interest in the scientific community. The objective of this review is to provide a complete understanding and knowledge of the synthesis methods and functionalization of various lignin nanoparticles (LNP). The characterization of LNP such as structural, thermal, molecular weight properties together with macromolecule and quantification assessments are also reviewed. In particular, emerging applications in different areas such as UV barriers, antimicrobials, drug administration, agriculture, anticorrosives, the environment, wood protection, enzymatic immobilization and others were highlighted. In addition, future perspectives and challenges related to the development of LNP are discussed.


Assuntos
Lignina
7.
Insects ; 2(4): 462-8, 2011 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-26467825

RESUMO

A study was carried out to test sisal (Agave sisalana Perrine) fiberboards properties as building materials against Asian subterranean termite, Coptotermes gestroi (Wasmann). Evaluation was in the laboratory according to the JWPA Standard-TW-S.1-1992. To improve mechanical properties of fiberboards made from sisal fibers, the boards were overlaid by rubber veneer, betung bamboo matting or formica. Result showed that the formica-overlaid sisal fiberboards performed better than other overlaid fiberboards against C. gestroi.

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