scholarly journals NANOFIBRILLATED CELLULOSE, THE SMALL PROMISING FIBER: CHARACTERISTICS AND POTENTIALITIES

FLORESTA ◽  
2019 ◽  
Vol 49 (3) ◽  
pp. 411
Author(s):  
Eliane Lopes da Silva ◽  
Helena Cristina Vieira ◽  
Joielan Xipaia dos Santos ◽  
Cyro Ketzer Saul ◽  
Silvana Nisgoski ◽  
...  
Keyword(s):  
Plant Material ◽  
Crystallinity Index ◽  
Nanofibrillated Cellulose ◽  
Decomposition Temperature ◽  
Degree Of Polymerization ◽  
Nanometer Scale ◽  
Infrared Analysis ◽  
Original Material ◽  
Cellulose Pulp ◽  
Eucalyptus Pulp

Cellulose: an abundant, biodegradable and renewable plant material that is available all around the globe, from which nanofibrillated cellulose (a homogeneous suspension of fibers with nanometer-scale diameters) can be extracted. The nanofibrillated cellulose, in what concerns its range of application, may completely or partially replace other materials due to its particular physical properties. Knowing its characteristics and properties is important in understanding its behavior in various applications. In light of this remarks, the objective of this research was to extract the nanocellulose from bleached eucalyptus pulp through mechanical milling to characterize the resulting nanofibrillated cellulose and compare both. The nanofibrillated cellulose presented a very distinct appearance in relation to the original cellulose pulp when they were analysed in the same concentrations, demonstrating greater water absorption and fibrillar interweaving. The nanofibrillated material showed different responses in comparison to the original in terms of dimensions, thermal stability, crystallinity, viscosity, and degree of polymerization. The nanofibrillated cellulose displays the same chemical composition through infrared analysis and has diameters of around 21.7 nm, smaller than the cellulose diameter of 11.4 μm. The nanofibrillated cellulose also exhibits lower thermal resistance: its decomposition temperature was about 20 ºC lower than that of the original cellulose pulp, and its crystallinity index has decreased. As for viscosity and degree of polymerization, there was reduction of 25% compared to the original material. The results presented hereby indicate that the nanofibrillated cellulose has unique features in relation to the original cellulose pulp, which supports its application as an alternative to existing materials.

Effects of mechanical fibrillation time by disk grinding on the properties of cellulose nanofibrils

TAPPI Journal ◽  
2016 ◽  
Vol 15 (6) ◽  
pp. 419-423 ◽  
Author(s):  
QIANQIAN WANG ◽  
J.Y. ZHU
Keyword(s):  
Energy Input ◽  
Cellulose Nanofibrils ◽  
Crystallinity Index ◽  
Degree Of Polymerization ◽  
Optical Transparency ◽  
Structure And Properties ◽  
Eucalyptus Pulp ◽  
Mechanical Fibrillation ◽  
Cnf Films ◽  
Grinding Time

Cellulose nanofibrils (CNF) were successfully produced from a bleach kraft eucalyptus pulp by a supermasscolloider. Effects of grinding time on structure and properties of CNF and the corresponding CNF films were investigated. Grinding time was important to increase the optical transparency of CNF suspensions. The degree of polymerization (DP) and crystallinity index (CrI) of CNF decreased linearly with the increase in CNF suspension transparency. This suggests optical transparency of a CNF suspension can be used to characterize the degree of fibrillation. Specific tensile strength and Young’s modulus of the CNF films made of CNF suspension with only 0.5 h grinding were increased approximately 30% and 200%, respectively, compared with conventional handsheets prepared by valley beating to 300 Canadian Standard Freeness (CSF). Energy input was only 1.38 kWh/kg for 0.5 h grinding. Grinding beyond 0.5 h produced negligible improvement in specific tensile and specific modulus. Opacity of CNF films decreased rapidly during the first 1.5 h of fibrillation and then plateaued.

scholarly journals Extraction and characterization of nanofibrillated cellulose from yacon plant (Smallanthus sonchifolius) stem

2020 ◽  
Author(s):  
Romaildo Santos de Sousa ◽  
Alan Sulato de Andrade ◽  
Maria Lucia Masson
Keyword(s):  
Lignin Content ◽  
Crystallinity Index ◽  
Nanofibrillated Cellulose ◽  
Lower Amount ◽  
Infrared Analysis ◽  
Technical Feasibility ◽  
Smallanthus Sonchifolius ◽  
Chemical Pulp ◽  
Chemical Pulping

This study aimed to evaluate the process of cellulose extraction from yacon stem using combined pulping and bleaching processes for produce nanofibrillated cellulose (NFC). First, chemical pulping process with NaOH was applied and, subsequently, the pulp obtained was bleached. From the chemical pulp (CP) bleached, NFC was obtained by the mechanical defibrillation in a colloidal grinder. Then, chemical composition, color, and infrared analysis of the pulps was performed. The pulping process showed a lower amount of extractives and lignin content, as a low yield and an excessively dark pulp. The CP bleached with NaClO2 showed the best results increased whiteness of the pulp. A suspension of NFC with fibers of 5–60 nm in diameter, high crystallinity index, and thermal stability was obtained. The results are promising and demonstrate the technical feasibility of obtaining NFC from yacon stems waste which is ideal to apply to other materials of the industry.

scholarly journals Novel Biobased Textile Fiber from Colombian Agro-Industrial Waste Fiber

Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2640 ◽  
Author(s):  
Maria Amaya Vergara ◽  
Melissa Cortés Gómez ◽  
Maria Restrepo Restrepo ◽  
Jorge Manrique Henao ◽  
Miguel Pereira Soto ◽  
...  
Keyword(s):  
Textile Industry ◽  
Industrial Waste ◽  
Degree Of Polymerization ◽  
Cellulose Content ◽  
Short Fibers ◽  
Cellulose Pulp ◽  
Potential Applications ◽  
Fique Fibers ◽  
Regenerated Fibers ◽  
Long Fibers

Fique fibers, native to Colombia, are traditionally used for ropes and bags. In the extraction of long fibers for these purposes, the same amount of short fibers is generated; the short fibers are then discarded in the soil or in landfills. This agro-industrial waste is cellulose-rich and can be potentially developed into new biobased products. As an alternative use for these fibers, viscose regenerated fibers with potential applications in the textile industry were developed. Fique waste fibers were pulped (to produce fique cellulose pulp, FCP) using a 33 design of experiment (DOE) to adjust the variables of the whitening treatment, and DOE analysis showed that time and hydrogen peroxide concentration do not have a significant effect on non-cellulosic remotion, unlike temperature. The behavior of this pulp in the production of viscose was compared against that of commercially available wood cellulose pulp (WCP). FCP showed a suitable cellulose content with a high degree of polymerization, which makes it a viable pulp for producing discontinuous viscose rayon filaments. Both pulps showed the same performance in the production of the viscose dope and the same chemical, thermal, and mechanical behavior after being regenerated.

scholarly journals Typification of Blechnum spicant var. fallax Lange (Blechnaceae)

2017 ◽  
Vol 86 (1) ◽  
Author(s):  
Paweł Wąsowicz ◽  
Łukasz Folcik ◽  
Adam Rostański
Keyword(s):  
Plant Material ◽  
Hot Springs ◽  
Original Material ◽  
Single Plant ◽  
Blechnum Spicant

<em>Blechnum spicant</em> var. <em>fallax</em> Lange is a fern taxon endemic to Iceland where it occurs in the vicinity of hot springs on geothermally heated soils. The taxon was first described by a Danish botanist Johan Martin Christian Lange in 1880 on the basis of plant material collected by Christian Grønlund in Iceland. Because its holotype was not designated in the protologue, we examined the extant original material including illustrations from <em>Flora Danica</em> and a single plant on sheet C10021769 (deposited in C) that was the basis for the respective plate. We select this specimen as the lectotype of <em>Blechnum spicant</em> var. <em>fallax</em>.

Effects of Treatments on Cellulosic Biomass Structure in Ethanol Manufacturing: A Literature Review

2011 ◽  
Author(s):  
Qi Zhang ◽  
Pengfei Zhang ◽  
Z. J. Pei ◽  
Linda Pei
Keyword(s):  
Particle Size ◽  
Enzymatic Hydrolysis ◽  
Literature Review ◽  
Crystallinity Index ◽  
Degree Of Polymerization ◽  
Cellulosic Biomass ◽  
Experimental Investigations ◽  
Structure Parameters ◽  
Transportation Fuels ◽  
Biomass Structure

Ethanol made from cellulosic biomass is an alternative to petroleum-based liquid transportation fuels. Enzymatic hydrolysis uses enzymes to convert cellulosic biomass into sugars that are fermented into ethanol. In order to increase sugar yield, various treatments (such as biomass size reduction and pretreatment) are applied to cellulosic biomass before enzymatic hydrolysis. These treatments will alter structure parameters of cellulosic biomass, such as crystallinity index, degree of polymerization, particle size, pore volume, and specific surface area. There are currently no review papers on these structure parameters of cellulosic biomass in ethanol manufacturing. This paper reviews experimental investigations in the literature about effects of various treatments on the structure parameters of cellulosic biomass.

scholarly journals Preparation of regenerated cellulose from rice straw lignocellulosic waste and its use for reinforced paper products

TAPPI Journal ◽  
2021 ◽  
Vol 20 (7) ◽  
pp. 439-451
Author(s):  
IZHAR ALAM ◽  
JITENDRA KUMAR ◽  
CHHAYA SHARMA
Keyword(s):  
Rice Straw ◽  
Fiber Length ◽  
Water Solution ◽  
Crystallinity Index ◽  
Degree Of Polymerization ◽  
Element Content ◽  
Hydroxyl Group ◽  
Regenerated Cellulose ◽  
Lignocellulosic Waste ◽  
Thawing Process

Rice straw waste is a lignocellulosic waste produced by farmers in large quantities. In this study, regenerated cellulose (RC) from rice straw was prepared by dissolving rice straw holocellulose (HC) in NaOH/Urea/Thiourea/Water solution by the freeze-thawing process. The crystallinity index of RC was calculated at 31%, which is out of the crystallinity range of 39%–69% that has been previously suggested. The study indicated that the RC is amorphous with a low degree of polymerization (638) and higher hydroxyl group content as compared to HC. The fiber length of RC was found to be 26.7% shorter; however, the width of RC was 21.2% higher as compared to HC. Reduced kinked fiber content was observed in the fraction of RC (18.3%) as compared with HC (39.1%), and a higher curl index of fiber was observed more so in HC (10.5%) than RC (5.6%). Because of the regeneration process, the fiber length was reduced and a fines element content of about 96% was observed in RC compared to the initial fines content of HC (56.9%). Irrespective of the high fines element content of RC, the composite paper of rice straw bleached pulp and RC fibers was developed with an increase in the tensile index from 41.4 N.m/g to 71.2 N.m/g and an increase in the burst index from 4.7 kPa.m2/g to 5.3 kPa.m2/g with the addition of 5% and 15% RC, respectively. However, enhanced tear index of paper was observed up to 5% and then it declined upon further addition of RC. The study revealed that regenerated cellulose can be used as a strength additive to overcome the shortcomings of low mechanical properties in paper products.

GREEN SYNTHESIS, CHARACTERIZATION AND ANTIMICROBIAL STUDIES OF MIXED LIGAND COMPLEXES OF Co (II), Ni (II) and V(III) METALS USING SOME AMINO ACIDS AS LIGANDS

2021 ◽  
Vol 4 (4) ◽  
pp. 191-199
Author(s):  
N. S. Gwaram ◽  
A. Salisu ◽  
Muhammad Manir
Keyword(s):  
Amino Acids ◽  
Metal Complexes ◽  
Conductivity Measurement ◽  
Antimicrobial Activities ◽  
Decomposition Temperature ◽  
Infrared Analysis ◽  
Antimicrobial Studies ◽  
Mixed Ligands ◽  
Method Of Continuous Variation ◽  
Job's Method

Co (II), Ni (II) and V (III) metal complexes were synthesized mechanochemically using L-Leucine, L-Tyrosine and Creatinine as mixed ligands. The metals and the ligands were grounded using an agate mortar with a pestle. The compounds formed were characterized using their melting/decomposition temperature, solubility, magnetic susceptibility, conductivity measurement, Infrared analysis and scanning electron microscope (SEM). The Metal – ligand ratios were investigated via Job’s method of continuous variation. The shifts of bands (for instance 1693-1677 cm-1 to 1674-1607 cm-1) in C=O and the appearance of new bands in the complexes (683-669 and 713-750 cm-1 indicates the complexation. The lower conductivity measurement values (15.00 to 32.40) µS.cm-1 suggested the non-electrolytic nature of the complexes. The magnetic effective value of the metal complexes showed that all the three complexes are paramagnetic and octahedral. It was concluded that the amino acids (ligands) coordinated in a bidentate way through the nitrogen from the amino group and oxygen from carboxylate. The complexes were screened for their antimicrobial activities against two bacterial isolates (Streptococcus pneumoniae and Klebsiella pneumoniae). All the complexes exhibited good activity against the organisms

Lectotype of Solidago ×niederederi (Asteraceae) selected from a recently rediscovered original material

Phytotaxa ◽  
2020 ◽  
Vol 438 (1) ◽  
pp. 62-64
Author(s):  
KATARÍNA SKOKANOVÁ ◽  
PAVOL MEREĎA Jr. ◽  
BARBORA ŠINGLIAROVÁ ◽  
STANISLAV ŠPANIEL
Keyword(s):  
Plant Material ◽  
Herbarium Specimens ◽  
Solidago Canadensis ◽  
Original Material ◽  
Field Margins ◽  
Forest Edges ◽  
Hybrid Species ◽  
Living Material ◽  
The 19Th Century ◽  
First Time

Solidago ×niederederi Khek (1905: 22) is a hybrid between North-American S. canadensis Linnaeus (1753: 878) and European native S. virgaurea Linnaeus (1753: 880). Solidago canadensis was introduced to Europe in the 17th century (Kowarik 2003). It has spread invasively throughout Europe since the second half of the 19th century (Weber 1998), reaching, besides sites disturbed by human activity, also (semi)natural biotopes, as forest edges, abandoned meadows and field margins which are often inhabited by native S. virgaurea. Their hybrid was discovered for the first time in nature by a local schoolmaster Franz Niedereder in the area of Vorderstoder village (Austria). Niedereder sent a plant material of the assumed hybrid to Eugen Johan Khek (born in 1861, Neuhaus/Jindřichov Hradec; died in 1927, Vienna), the pharmacist and botanist who lived in Vienna since 1889 (Anonymous 1916). Khek described the hybrid species under the name S. ×niederederi in honour of his discoverer (Khek 1905). The protologue indicates that the relevant communication between Niedereder and Khek was going on between July 1900 (when they met for the first time) and February 1905 (when the hybrid’s description was published). Before its description, Khek studied the hybrid for four years and he saw a herbarium material from Niedereder as well as a living material. In the protologue, no particular herbarium specimens or illustrations had been indicated or associated with S. ×niederederi (Khek 1905).

Nanofibrillated cellulose as nanoreinforcement in Portland cement: Thermal, mechanical and microstructural properties

2016 ◽  
Vol 51 (17) ◽  
pp. 2491-2503 ◽  
Author(s):  
Roukaya Mejdoub ◽  
Halim Hammi ◽  
Joan Josep Suñol ◽  
Mohamed Khitouni ◽  
Adel M‘nif ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Cement Hydration ◽  
Coefficient Of Thermal Expansion ◽  
Nanofibrillated Cellulose ◽  
Partial Replacement ◽  
Cellulose Content ◽  
Cement Pastes ◽  
Eucalyptus Pulp ◽  
Reinforced Cement ◽  
Mechanical And Microstructural Properties

Nanofibrillated cellulose from eucalyptus pulp, produced by high-pressure homogenization, was used as cement partial replacement for cement paste at a content ranging from 0% to 0.5% by weight of cement. The effect of the content of nanofibrillated cellulose on porosity, thermal properties, compressive strength and degree of cement hydration was investigated. Results have shown an improvement in the compressive strength by more than 50% with 0.3 wt% of added nanofibrillated cellulose. The porosity was reduced by nanofibrillated cellulose addition, and the greatest result was achieved with mixture incorporating 0.3 wt% nanofibrillated cellulose. The coefficient of thermal expansion and the thermal conductivity measurements, relative to nanofibrillated cellulose-reinforced cement pastes, have pointed out the reinforcement effectiveness of nanofibrillated cellulose. The degree of cement hydration has increased with nanofibrillated cellulose content. This trend was confirmed by X-ray diffraction and Fourier Transform Infrared spectroscopy. These analyses have revealed that the presence of nanofibrillated cellulose promoted the hydration of cement, by producing more portlandite and calcium silicate gel, which is likely the main reason accounting for the strong enhancement in the compressive strength.

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