scholarly journals Ubim Fiber (Geonoma baculífera): A Less Known Brazilian Amazon Natural Fiber for Engineering Applications

2021 ◽  
Vol 14 (1) ◽  
pp. 421
Author(s):  
Belayne Zanini Marchi ◽  
Michelle Souza Oliveira ◽  
Wendell Bruno Almeida Bezerra ◽  
Talita Gama de Sousa ◽  
Verônica Scarpini Candido ◽  
...  
Keyword(s):  
Natural Fiber ◽  
Microfibril Angle ◽  
Crystallinity Index ◽  
X Ray Diffraction ◽  
Fiber Density ◽  
Engineering Applications ◽  
Synthetic Fibers ◽  
Lignocellulosic Fibers ◽  
Synthetic Materials ◽  
Promising Application

The production of synthetic materials generally uses non-renewable forms of energy, which are highly polluting. This is driving the search for natural materials that offer properties similar to synthetic ones. In particular, the use of natural lignocellulosic fibers (NLFs) has been investigated since the end of 20th century, and is emerging strongly as an alternative to replace synthetic components and reinforce composite materials for engineering applications. NLFs stand out in general as they are biodegradable, non-polluting, have comparatively less CO2 emission and are more economically viable. Furthermore, they are lighter and cheaper than synthetic fibers, and are a possible replacement as composite reinforcement with similar mechanical properties. In the present work, a less known NLF from the Amazon region, the ubim fiber (Geonoma bacculifera), was for the first time physically characterized by X-ray diffraction (XRD). Fiber density was statistically analyzed by the Weibull method. Using both the geometric method and the Archimedes’ technique, it was found that ubim fiber has one of the lowest densities, 0.70–0.73 g/cm3, for NLFs already reported in the literature. Excluding the porosity, however, the absolute density measured by pycnometry was relatively higher. In addition, the crystallinity index, of 83%, microfibril angle, of 7.42–7.49°, and ubim fiber microstructure of lumen and channel pores were also characterized by scanning electron microscopy. These preliminary results indicate a promising application of ubim fiber as eco-friendly reinforcement of civil construction composite material.

A NOVEL STUDY ON SURFACE MODIFICATION OF PALMYRA FIBERS FOR ENHANCING MECHANICAL AND THERMAL PROPERTIES

2019 ◽  
Vol 27 (02) ◽  
pp. 1950104
Author(s):  
T. RAGHAVENDRA ◽  
K. PANNEERSELVAM
Keyword(s):  
Tensile Strength ◽  
Natural Fiber ◽  
Crystallinity Index ◽  
Mechanical And Thermal Properties ◽  
X Ray Diffraction ◽  
Energy Dispersion Spectroscopy ◽  
Lignocellulosic Fibers ◽  
Degradation Temperature ◽  
Main Effect ◽  
Increasing Temperature

Natural fiber reinforcing in engineering thermoplastics (Nylon melting point around 230∘C) is challenging, due to the lower degradation temperature ([Formula: see text]C) of lignocellulosic fibers. Further, increasing temperature (beyond 200∘C) results in weakening of its mechanical properties. In this investigation, camphor soot reinforced palmyra fibers (CSRPF) are manufactured by osmosis with the help of design of experiments (DOE) and are examined for different time (4, 8 and 12[Formula: see text]h), temperature (30∘C, 40∘C and 50∘C) and camphor soot concentrations (0.5, 1.0 and 1.5[Formula: see text]wt.%) using L9 orthogonal array. The osmosis rate of modified fibers was calculated and tested for their tensile strength as the osmosis rate and tensile strength are the main objective functions. Based on DOE and taguchi-ANOVA analysis, optimal parameters were obtained through main effect plots and Anova results. Further, an optimal combination of parameters for CSRPF was characterized for thermogravimetric analysis (TGA), Fourier transform infrared radiation (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS) to inspect and compare it with neat palmyra fibers. There was considerable improvement in the CSRPF tensile strength about 84[Formula: see text]Mpa with respect to neat palmyra fibers which is 58[Formula: see text]MPa. TGA reveals the degradation temperature of neat palmyra fiber is about 225∘C and it is enhanced in case of CSRPF about 265∘C which accounts for 15% enhanced thermal stability. The crystallinity index (CI) of CSRPF was reduced marginally compared to the neat palmyra fibers. FTIR analysis showed the peak drift marginally to the left in CSRPF due to the coating of camphor soot particles. The microstructure of both neat and CSRPF are examined using SEM and EDS which shows that 93.71% carbon was present in the cross section of CSRPF compared to the neat palmyra fiber (62.58%).

scholarly journals A Review on Application of Single and Hybrid Fiber Reinforced Polymer Composites

2020 ◽  
pp. 325-327
Author(s):  
Sumesh K R ◽  
Kanthavel K ◽  
Saikrishnan G
Keyword(s):  
Polymer Composites ◽  
Polymer Matrix ◽  
Natural Fiber ◽  
Alkali Treatment ◽  
Natural Fibers ◽  
Crystallinity Index ◽  
Practical Applications ◽  
Synthetic Fibers ◽  
Reinforced Polymer ◽  
Fiber Reinforced Polymer Composites

The applications of natural fiber composites have enormously increased due to the high availability, eco-friendly nature and practical applications of the composites. In this review different fiber combinations using natural fiber and synthetic fibers have been investigated and found with interesting results. The hybrid nature of fiber reinforcement adds to the mechanical properties of polymer-based composites. The hybridization using more than one fiber reduces the surface deformations in the polymer matrix and enhanced the bonding ability of polymer composites. The alkali treatment was the effective surface treatment process for improving the cellulosic nature with good crystalline nature, good bonding ability with the polymer matrix, this adds to the properties of polymer-based composites. The crystallinity index of 43-68 % were observed in surface treated natural fibers.

Preparation and Characterization of Physical Properties of Durian Skin Fibers Biocomposite

2012 ◽  
Vol 576 ◽  
pp. 212-215 ◽  
Author(s):  
R.M. Manshor ◽  
Hazleen Anuar ◽  
Wan Busu Wan Nazri ◽  
M.I. Ahmad Fitrie
Keyword(s):  
Natural Fiber ◽  
Natural Fibers ◽  
Crystallinity Index ◽  
Average Diameter ◽  
Environmental Scanning ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lignocellulosic Fiber ◽  
The Common

Durian skin fibres (DSF) are cellulose-based fibres extracted from the durian peel. This paper present the physical behaviour, chemical structure and crystallinity of the fibres, as observed by environmental scanning electron microscope (ESEM), Fourier transform infrared (FTIR) and X-ray diffraction (XRD). The characteristic of the natural fibers produces from durian skins are similar with other types of natural fiber. The average diameter and density are 0.299 mm and 1.243 g/cm3, respectively while the crystallinity index is slightly higher than the common fibers. The properties and charecteristic of durian skin fibers are within the propertise of lignocellulosic fiber which is suitable for development of biocomposite materials.

scholarly journals Characterization of natural cellulosic fiber isolated from Malaysian Cymbopogan citratus leaves

BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 7729-7750
Author(s):  
Zatil Hafila Kamaruddin ◽  
Ridhwan Jumaidin ◽  
Ahmad Ilyas Rushdan ◽  
Mohd Zulkefli Selamat ◽  
Roziela Hanim Alamjuri
Keyword(s):  
Chemical Composition ◽  
Natural Fiber ◽  
Morphological Characteristics ◽  
Crystallinity Index ◽  
Composition Analysis ◽  
Green Composite ◽  
X Ray Diffraction ◽  
First Time ◽  
Cymbopogan Citratus

A novel natural fiber derived from the Cymbopogan citratus plant was investigated for the first time. The characterization of the C. citratus fibers was conducted, and the chemical composition and physical, thermal, mechanical, crystallinity, and morphological characteristics were studied. The chemical composition analysis of Cymbopogan citratus fiber revealed that the suggested fiber was rich in cellulose contents (37.6%). The tensile test of C. citratus fiber demonstrated the fiber’s average tensile strength of 43.81 ± 15.27 MPa and modulus of elasticity of 1.046 ± 0.33 GPa. Further analysis with X-ray diffraction (XRD) confirmed that the crystallinity index of Cymbopogan citratus fiber was 35.2%, and the crystalline size was estimated as 4.28 nm. The Cymbopogan citratus fiber’s thermal stability was investigated via thermogravimetric analysis (TGA) and observed to be thermally stable (230 °C). A morphological investigation was employed on the fiber via a scanning electron microscope (SEM). The morphological study result exhibited that the fiber had a perforated and rough surface with the lumen in the center. Thus, the findings revealed that the Cymbopogan citratus fiber was a promising potential reinforcement for thermoplastic green composite applications.

scholarly journals Characterization of a new natural fiber extracted from Corypha taliera fruit

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Taslima Ahmed Tamanna ◽  
Shah Alimuzzaman Belal ◽  
Mohammad Abul Hasan Shibly ◽  
Ayub Nabi Khan
Keyword(s):  
Tensile Strength ◽  
Natural Fiber ◽  
Natural Fibers ◽  
Morphological Characteristics ◽  
Synthetic Fiber ◽  
X Ray Diffraction ◽  
Reinforced Composite ◽  
Potential Alternative

AbstractThis study deals with the determination of new natural fibers extracted from the Corypha taliera fruit (CTF) and its characteristics were reported for the potential alternative of harmful synthetic fiber. The physical, chemical, mechanical, thermal, and morphological characteristics were investigated for CTF fibers. X-ray diffraction and chemical composition characterization ensured a higher amount of cellulose (55.1 wt%) content and crystallinity (62.5%) in the CTF fiber. The FTIR analysis ensured the different functional groups of cellulose, hemicellulose, and lignin present in the fiber. The Scherrer’s equation was used to determine crystallite size 1.45 nm. The mean diameter, specific density, and linear density of the CTF fiber were found (average) 131 μm, 0.86 g/cc, and 43 Tex, respectively. The maximum tensile strength was obtained 53.55 MPa for GL 20 mm and Young’s modulus 572.21 MPa for GL 30 mm. The required energy at break was recorded during the tensile strength experiment from the tensile strength tester and the average values for GL 20 mm and GL 30 mm are 0.05381 J and 0.08968 J, respectively. The thermal analysis ensured the thermal sustainability of CTF fiber up to 230 °C. Entirely the aforementioned outcomes ensured that the new CTF fiber is the expected reinforcement to the fiber-reinforced composite materials.

scholarly journals Chemical and Structural Characterization of Maize Stover Fractions in Aspect of Its Possible Applications

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1527
Author(s):  
Magdalena Woźniak ◽  
Izabela Ratajczak ◽  
Dawid Wojcieszak ◽  
Agnieszka Waśkiewicz ◽  
Kinga Szentner ◽  
...  
Keyword(s):  
Structural Characterization ◽  
Biogas Production ◽  
Structural Parameters ◽  
C:N Ratio ◽  
Crystallinity Index ◽  
Degree Of Crystallinity ◽  
Cellulose Content ◽  
X Ray Diffraction ◽  
Maize Stover

In the last decade, an increasingly common method of maize stover management is to use it for energy generation, including anaerobic digestion for biogas production. Therefore, the aim of this study was to provide a chemical and structural characterization of maize stover fractions and, based on these parameters, to evaluate the potential application of these fractions, including forbiogas production. In the study, maize stover fractions, including cobs, husks, leaves and stalks, were used. The biomass samples were characterized by infrared spectroscopy (FTIR), X-ray diffraction and analysis of elemental composition. Among all maize stover fractions, stalks showed the highest C:N ratio, degree of crystallinity and cellulose and lignin contents. The high crystallinity index of stalks (38%) is associated with their high cellulose content (44.87%). FTIR analysis showed that the spectrum of maize stalks is characterized by the highest intensity of bands at 1512 cm−1 and 1384 cm−1, which are the characteristic bands of lignin and cellulose. Obtained results indicate that the maize stover fraction has an influence on the chemical and structural parameters. Moreover, presented results indicate that stalks are characterized by the most favorable chemical parameters for biogas production.

scholarly journals Influence of Rigid Brazilian Natural Fiber Arrangements in Polymer Composites: Energy Absorption and Ballistic Efficiency

2021 ◽  
Vol 5 (8) ◽  
pp. 201
Author(s):  
Fabio C. Garcia Filho ◽  
Fernanda S. Luz ◽  
Michelle S. Oliveira ◽  
Wendell B. A. Bezerra ◽  
Josiane D. V. Barbosa ◽  
...  
Keyword(s):  
Polymer Composites ◽  
Energy Absorption ◽  
Natural Fiber ◽  
High Energy ◽  
Matrix Composites ◽  
Lignocellulosic Fibers ◽  
Efficiency Performance ◽  
Epoxy Matrix Composite ◽  
Polymeric Matrix Composites ◽  
Armor System

Since the mid-2000s, several studies were carried out regarding the development of ballistic resistant materials based on polymeric matrix composites reinforced with natural lignocellulosic fibers (NLFs). The results reported so far are promising and are often comparable to commonly used materials such as KevlarTM, especially when used as an intermediate layer in a multilayer armor system (MAS). However, the most suitable configuration for these polymer composites reinforced with NLFs when subjected to high strain rates still lacks investigation. This work aimed to evaluate four possible arrangements for epoxy matrix composite reinforced with a stiff Brazilian NLF, piassava fiber, regarding energy absorption, and ballistic efficiency. Performance was evaluated against the ballistic impact of high-energy 7.62 mm ammunition. Obtained results were statistically validated by means of analysis of variance (ANOVA) and Tukey’s honest test. Furthermore, the micromechanics associated with the failure of these composites were determined. Energy absorption of the same magnitude as KevlarTM and indentation depth below the limit predicted by NIJ standard were obtained for all conditions.

scholarly journals Valorization of Byproducts of Hemp Multipurpose Crop: Short Non-Aligned Bast Fibers as a Source of Nanocellulose

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4723
Author(s):  
Sara Dalle Vacche ◽  
Vijayaletchumy Karunakaran ◽  
Alessia Patrucco ◽  
Marina Zoccola ◽  
Loreleï Douard ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Thermogravimetric Analysis ◽  
Cannabis Sativa ◽  
Crystallinity Index ◽  
Residual Lignin ◽  
Chemical Pretreatment ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bast Fibers ◽  
Seed Maturity

Nanocellulose was extracted from short bast fibers, from hemp (Cannabis sativa L.) plants harvested at seed maturity, non-retted, and mechanically decorticated in a defibering apparatus, giving non-aligned fibers. A chemical pretreatment with NaOH and HCl allowed the removal of most of the non-cellulosic components of the fibers. No bleaching was performed. The chemically pretreated fibers were then refined in a beater and treated with a cellulase enzyme, followed by mechanical defibrillation in an ultrafine friction grinder. The fibers were characterized by microscopy, infrared spectroscopy, thermogravimetric analysis and X-ray diffraction after each step of the process to understand the evolution of their morphology and composition. The obtained nanocellulose suspension was composed of short nanofibrils with widths of 5–12 nm, stacks of nanofibrils with widths of 20–200 nm, and some larger fibers. The crystallinity index was found to increase from 74% for the raw fibers to 80% for the nanocellulose. The nanocellulose retained a yellowish color, indicating the presence of some residual lignin. The properties of the nanopaper prepared with the hemp nanocellulose were similar to those of nanopapers prepared with wood pulp-derived rod-like nanofibrils.

Isolation and characterization of lignocellulosic fiber from jute bast by the organic solvent degumming system: an alkali-free method

2021 ◽  
pp. 004051752110154
Author(s):  
Zhihui Qin ◽  
Shuyuan Zhao ◽  
Liu Liu ◽  
Zhaohe Shi ◽  
Longdi Cheng ◽  
...  
Keyword(s):  
National Standards ◽  
X Ray Diffraction ◽  
High Concentration ◽  
X Ray ◽  
Lignocellulosic Fibers ◽  
Lignocellulosic Fiber ◽  
Isolation And Characterization ◽  
Alkali Consumption ◽  
Scanning Electron

Degumming is the dominant method for insolating lignocellulosic fibers in textile applications. Traditional alkaline degumming (TAL), as a common method, requires a high-concentration alkali and has been a severe challenge to the environment. In the research reported here, the possibility of innovative jute degumming by organic solvents 1-2 propylene glycol and a combination of additive green oxygen (GO-OS) was studied. The results revealed that fibers could be extracted by this system (under condition of 0.9% GO-OS, 180°C, 120 min), and obtained fibers with higher breaking tenacity (7.1 cN/dtex), yield (65.7%), breaking elongation (2.87%) and residual gum (11.7%), which all meet the requirement of the relevant Chinese Textile National Standards. Notably, the required reaction time (120 min) of the GO-OS system was 180 min shorter than that of the TAL method. Furthermore, the modifications introduced by the degumming effect on physicochemical aspects were characterized and confirmed by Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray diffraction. This study provides a promising degumming method for separating jute lignocellulose without acid and alkali consumption.

Twin memory and twin amnesia in anorthoclase

2000 ◽  
Vol 64 (2) ◽  
pp. 195-200 ◽  
Author(s):  
S. A. Hayward ◽  
E. K. H. Salje
Keyword(s):  
Phase Transitions ◽  
Transition Temperature ◽  
Alkali Feldspar ◽  
Spatial Distributions ◽  
X Ray Diffraction ◽  
Alkali Cations ◽  
X Ray ◽  
Natural Minerals ◽  
Synthetic Materials ◽  
Before And After

AbstractMany natural minerals and synthetic materials display twin microstructures resulting from displacive phase transitions. These microstructures may be removed temporarily from the sample by heating above the relevant transition temperature, though the twinning generally returns on subsequent cooling.In anorthoclase, the spatial distributions of twins before and after brief annealing above TC are often identical. This property appears to be a common feature in many materials which undergo ferroelastic phase transitions, and is known as ‘twin memory’. The atomic mechanisms responsible for this twin memory may be investigated by studying the annealing regimes required to remove the memory effect; how long must a sample be annealed, and at what temperature, to induce ‘twin amnesia’.High-resolution X-ray diffraction (XRD) has been used to investigate twin memory and twin amnesia in anorthoclase. In anorthoclase, the primary constraint on twin amnesia is thermodynamic, rather than kinetic. The critical temperature to induce amnesia correlates well with the top of the (Na, K) solvus in disordered alkali feldspar. For this reason, the proposed mechanism for twin memory involves the segregation of alkali cations in thin lamellae at the twin boundaries.

Sign in / Sign up

Export Citation Format

Share Document