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1.
Physiol Plant ; 176(3): e14368, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38837358

RESUMO

Biobased waste utilization is an intriguing area of research and an ecologically conscious approach. Plant-based materials can be used to render cellulose, which is an eco-friendly material that can be used in numerous aspects. In the current investigation, cellulose was extracted from the leaves of the Vachellia nilotica plant via acid hydrolysis. The application of this research is specifically directed toward the utilization of undesirable plant sources. To validate the extracted cellulose, FT-IR spectroscopy was applied. The cellulose was measured to have a density of 1.234 g/cm3. The crystallinity index (58.93%) and crystallinity size (11.56 nm) of cellulose are evaluated using X-ray diffraction spectroscopy analysis. The highest degradation temperature (320.8°C) was observed using thermogravimetry and differential scanning calorimetry curve analysis. The analysis of particle size was conducted utilizing images captured by scanning electron microscopy. Particle size of less than 30 µm was found and they exhibit non-uniform orientation. Additionally, atomic force microscopy analysis shows an improved average surface roughness (Ra), which increases the possibility of using extracted cellulose as reinforcement in biofilms.


Assuntos
Biomassa , Celulose , Folhas de Planta , Difração de Raios X , Celulose/química , Celulose/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Varredura , Microscopia de Força Atômica , Tamanho da Partícula , Hidrólise
2.
Int J Biol Macromol ; 138: 573-581, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31348971

RESUMO

The objective of this investigation is to check the suitability novel cellulosic fibre extracted from the aerial roots of Banyan tree (ARBFs) as reinforcement in fibre reinforced plastics. The Fundamental properties of ARBFs such as density, tensile strength, chemical composition, crystallinity index, crystalline size, thermal stability, maximum degradation temperature and surface roughness were studied. The chemical analysis results revealed that after the alkalization cellulose content was improved while hemi-cellulose, lignin and wax content were demised. The enhancement in the crystallinity index (76.35% from 72.47%) and crystalline size (7.74 nm from 6.28 nm) of alkali treated ARBFs were evidenced by the X-ray diffraction analysis. Thermal analysis results confirmed that maximum degradation temperature (368 °C) and kinetic activation energy (75.45 kJ/mol) of alkali treated ARBFs had increased from 358 °C and 72.65 kJ/mol respectively. The results of scanning electron microscopic and atomic force microscopic analysis exhibited that impurities and wax on the outer surface of the ARBFs were removed after the alkali treatment. All the above finding concluded that ARBFs is the appropriate material to use as a reinforcement in fibre reinforced plastics.


Assuntos
Álcalis/química , Celulose/química , Ficus/química , Raízes de Plantas/química , Árvores/química , Celulose/ultraestrutura , Análise Espectral , Resistência à Tração , Termogravimetria
3.
Carbohydr Polym ; 186: 332-343, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29455994

RESUMO

The physical, chemical, tensile, crystalline, thermal, and surface morphological properties of raw and alkali treated Coccinia Grandis.L Fibers (CGFs) were characterized for the first time in this work. The results of the chemical analysis indicate that, after alkali treatment, the cellulose content of CGFs increased whereas hemicelluloses, lignin and wax contents decreased. This directly influenced the tensile strength, crystallinity index, thermal stability and the roughness of alkali-treated CGFs. The thermal stability and activation energy of the CGFs improved from 213.4 °C to 220.6 °C and 67.02 kJ/mol to 73.43 kJ/mol, respectively, due to alkali treatment. The statistical approach, Weibull distribution was adopted to analyze the tensile properties. The improved properties of the alkali treated CGF indicate that it could be an appropriate material for reinforcement in polymer composites.


Assuntos
Celulose/química , Cucurbitaceae/química , Microscopia Eletrônica de Varredura , Polímeros/química , Resistência à Tração
4.
Carbohydr Polym ; 181: 650-658, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29254019

RESUMO

The exploration of new natural fibers in the field of polymer composites can contribute to increase the invention of natural reinforcements and expand their use in possible applications. In the present work, the physico-chemical, thermal, tensile and morphological properties of Furcraea foetida (FF) fiber are presented for the first time. Chemical analysis results shows that FF has relatively higher cellulose (68.35%) with lower hemicelluloses (11.46%) and lignin (12.32%). Structural analysis of FF was conducted by Fourier transform infrared and 13C (CP-MAS) nuclear magnetic resonance spectroscopy. X-ray diffraction (XRD) analysis evidenced that FF has crystallinity index of 52.6% with crystalline size of 28.36nmThe surface morphology of FF was investigated by scanning electron microscopy (SEM), energy dispersive X-ray micro analyzer (EDX) and atomic force microscopy (AFM). The thermogravimetric analysis (TGA) reveals thermal constancy of the fiber upto 320.5°C with the kinetic activation energy of 66.64kJ/mol, which can be used as reinforcements in thermoplastic green composite whose working temperatures is below 300°C. The FF results were compared with those of other natural fibers, and indicated as a suitable alternative source for composite manufacture.

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