Effect Of Alkali Treatment Research Articles

Effect of Alkali Treatment under Ambient and Heated Conditions on the Physicochemical, Structural, Morphological, and Thermal Properties of Calamus tenuis Cane Fibers

This study explores the effect of alkali treatment at ambient (25 °C) and elevated temperatures (100 °C) on the physicochemical, structural, morphological, and thermal properties of Calamus tenuis cane fibers (CTCFs) for the first time. Our purpose is to investigate their potential use as reinforcement in polymer composites, since cane fibers are generally known for their accurate and consistent geometrical orientation. Treatment with 8% (w/v) sodium hydroxide (NaOH) is carried out at ambient temperature and at 100 °C for 4 h. Chemical analysis and Fourier transform IR spectroscopy (FTIR) indicate some removal of non-cellulosic elements from CTCFs during alkali treatment, resulting in increased surface roughness, as confirmed by using SEM micrographs. This removal of non-cellulosic elements leads to an enhancement in the density of the treated CTCFs. Untreated and treated fibers are analyzed for maximum degradation temperature, thermal stability, and kinetic activation energy (Ea) using thermogravimetric analysis (TGA). In particular, Ea was considerably diminished with treatment and temperature. X-ray diffraction (XRD) results show an improved crystallinity index (37.38% to 44.02%) and crystallite size (2.73 nm to 2.98 nm) for fibers treated with 8% NaOH at ambient temperature. In conclusion, a general benefit was achieved by treating CTCFs, though the influence of increasing temperature treatment appears controversial.

Characterization of tool-ply friction behavior for treated jute/PLA biocomposite prepregs in thermoforming

This paper investigates the tool-ply friction behavior of woven jute fabric reinforced poly-lactic acid (jute/PLA) biocomposite in thermoforming. A home-made pull-through friction testing device was developed to characterize the tool-ply friction behavior of the jute/PLA prepreg at elevated temperature. The effects of alkali treatment, fiber orientation, normal force and slipping velocity were studied. The results suggested a strong relationship between the tool-ply friction behavior and the woven and fiber structures. In addition, a quantitative definition of the tool-ply friction behavior was achieved by introducing the characteristic stress and friction coefficient. These findings indicated a hydrodynamic lubrication of tool-ply friction. This work provides a beneficial complement to the understanding of the thermoforming process of jute/PLA biocomposites.

Optimization of the novel jute retting process to enhance the fiber quality for textile applications

This study introduces an innovative chemical retting approach, systematically optimized via Grey relational analysis, to achieve jute fibers that exhibit desirable characteristics of softness, high tensile strength, and suitability for spinning, with a particular focus on their application in the apparel industry. In this study, the effect of alkali treatment (alkali concentration, temperature and duration of retting) on jute fiber's chemical composition and mechanical characteristics was investigated. Jute fibers were treated at three concentrations (5 %, 10 %, 15 %) of alkali, at three different temperature (30 °C, 60 °C, & 90 °C) and for three different retting duration (12 h, 24 h, & 36 h). The surface morphology and crystallinity of fibers were analyzed using optical microscopy, X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The fiber linear density and mechanical characteristics were also tested. The multi-response optimization of all the factors and the responses was investigated using the Grey relational analysis. The results showed that the fiber surface morphology and crystallinity increase with an increase in alkali concentration, retting time, and temperature. Chemical retting treatment also improved the fiber linear density and tensile strength. The finest fibers which were obtained in this research had a linear density of 2.18 Tex with a tenacity of 53.02 cN/tex and elongation of 4.54 %. The spinnable jute fibers were achieved after this treatment with excellent characteristics.

The effect of alkali treatment on the mechanical properties of date seed particulates waste polypropylene filled composites

Date seeds collected as waste were reduced to 63 µm particles and treated with NaOH (aq) at 1, 3, 5, 7 and 10 %. The extent of chemical modification was assessed using FTIR analysis. The waste polypropylene (wPP)/date seed particles (DSP) composites filled with untreated and treated particles at 20 % filler loadings were fabricated using compounding and compression moulding techniques by means of two rolls mill. Tensile, flexural, impact tests and hardness (HV) were conducted and evaluated. Subsequently, a morphological study of the fractured surface of the composites was achieved using SEM. The application of alkali treatment enhanced various properties of the composites at the optimal concentration of 10 % w/v. Specifically, the tensile strength, flexural strength, elongation at break, impact strength, and hardness were improved, resulting in values of 28.86 MPa, 140 MPa, 172.5 %, 0.92 J/m², and 23.8 Hv, respectively. While tensile and flexural moduli showed a decrease with increasing alkali concentration. The SEM of the fractured surface of the treated composite revealed a better dispersion of filler particles within the matrix with no cluster seen compared to the untreated.

Preparation and properties of PVC composites filled with walnut shell powder hybrid attapulgite

AbstractIn order to reveal the effect of alkali treatment of walnut shell (WS) powder and attapulgite (ATP) hybrid filling on the properties of WS/polyvinyl chloride (PVC) composites, and to compare the effects of different reinforcement methods, WS/PVC composites were prepared by single screw melt extrusion. Furthermore, analysis was conducted on the chemical composition, thermal stability, microstructure, and physical, mechanical and wear resistance properties of composites. The results showed that ATP hybrid can enhance the performance of WPC more effectively than alkali treatment, unmodified WS blended with ATP composites have the best physical, mechanical properties, abrasive wear resistance, as well as lower water absorption, compared with the untreated, the tensile strength, bending strength and impact strength increased by 24%, 8%, and 21%, respectively. In addition, the composites of ATP hybrid alkali treated WS have the best thermal stability, and its pyrolysis residue is 15.64% higher than untreated composites. The study found that ATP have a larger potential to enhance the properties of composites than alkali treatment.Highlights Chemical treatment and inorganic mineral particle filling were used to enhance the properties of the WS/PVC composites. The experimental results showed that attapulgite can maximize the properties of the composites without alkali treatment. This means that attapulgite filling is a more effective and environmentally friendly and simple method to enhance the properties of composites than alkali treatment. The wear failure modes of the composites are mainly micro‐indentation and micro‐cutting.

Elastic transparent lignocellulose bioplastics from corncob waste: positive effects of alkali treatment without bleaching process

Elastic transparent lignocellulose bioplastics from corncob waste: positive effects of alkali treatment without bleaching process

Effect of alkali treatment on properties of Palmyra palm tree primary flower leaf stalk fiber–reinforced polymer composites

Effect of alkali treatment on properties of Palmyra palm tree primary flower leaf stalk fiber–reinforced polymer composites

ANALISIS PENGARUH VARIASI WAKTU PERLAKUAN ALKALI TERHADAP KEKUATAN IMPACT KOMPOSIT POLYESTER YANG DIPERKUAT SERAT BAMBU

This study aimed to determine the effect of alkali treatment on the impact strength and fracture pattern of bamboo fiber reinforced polyester composites. This composite consisted of polyester resin as a matrix and bamboo fiber as a filler or reinforcement. The alkaline treatment time used was 5% NaOH from 1 hour to 4 hours and to determine the microscopic image of the fracture pattern of the impact test specimen. This study used an experimental method with the dependent variable being the impact strength and microscopic images of the fracture pattern, and the independent variable was the alkali treatment time 1 hour, 2 hours, 3 hours and 4 hours. Specimens were printed using the hand lay-up method. The impact strength was known by performing consecutive tests based on ASTM D 6110-04. Based on the results of the impact test, it showed that the impact strength increased until the alkaline treatment 2 hours ago and decreased at 3 hours, and 4 hours. The highest impact strength was shown in the alkaline treatment of bamboo fiber rope 2 hours with an impact strength value of 1373.89 J/M2. The examination of the microscopic image of the fracture pattern obtained the best fracture in 2 hours alkali treatment with a brittle fracture mechanism.

INVESTIGATION INTERFACIAL SHEAR STRENGTH AND MECHANICAL PROPERTIS OF ALKALI TREATED HONEY PINEAPPLE FIBER/ MICROCRYSTALLINE CELLULOSE COMPOSITE

The research objective was investigate the effect of alkali treatment on thermal stability, interfacial shear strength, mechanical properties and waterabsorption in composite of honey pineapple fiber (HPF). HPF was not given and treated by soaking in a mixture of 6% wt sodium hydroxide. Mixing between Unsaturated Polyester (UPRs) and Microcrystalline Cellulose (MCC) applied the Taguchi test with 5% MCC, 250 RPm, 40 oC temperature, and 30 minutes. The composites were mold using the vacuum infusion method and curing at 60 o C for 120 minutes. Interfacial shear strength test showed 9 hours of immersion, gave strength of 3.49 MPa, an increase of 37.39%. Tensile strength increased by 30.4%,the flexural strength of the composite increased by 51.08%. The results of the SEM test showed the fiber untreated was still smooth and there were several interface gaps. The water absorption test showed that the untreated fiber had a higher absorption rate.

Effect of alkali treatment on wear behaviour of walnut shell reinforced bio-composites

In this study, the tribological behaviour of composites reinforced with walnut shells (0 % to 10 % at 2 % interval) has been investigated. The pin-on-disc machine is used us to observe the impact of walnut shell addition on the wear properties of the composite. An increase in walnut shell content is associated with diminished wear resistance. Inadequate adhesion among the fibre and the matrix was also identified as the cause of this wear strength degradation in testing results. Pre-treatment of walnut shell with sodium hydroxide increases wear resistance by strengthening matrix adherence to fibre. Different normal loads (from 6 N to 48 N), sliding velocities of 100 cm/s, and sliding distances (SD) of 0 to 2000 m were all considered in the experiments. The findings revealed that operation settings and filler reinforcement have an important impact on the wear behaviour of composite containing walnut shell filler. In comparison to dry and hot contact, the specific wear rate (SWR) is nearly 7 to 8 times lesser in wet conditions. Additionally, equated to a composite with a higher filler loading, the performance of one with a lesser loading of walnut shell filler was superior in terms of wear.

Effect of alkali treatment on novel natural fiber extracted from palmyra palm primary flower leaf stalk for polymer composite applications

Effect of alkali treatment on novel natural fiber extracted from palmyra palm primary flower leaf stalk for polymer composite applications

Effect of Alkali Treatment and Fibre Composition on the Performance of Pineapple Leaf Fiber-Polyvinyl Alcohol Composites

This paper studied the properties of composites based on polyvinyl alcohol reinforced with pineapple leaf fibres (PALF/PVA). The surface of pineapple leaf fibres (PALF) has been previously treated with 6% sodium hydroxide solution. The influence of fibre loading and fibre surface treatment were examined. Analysis by Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) displayed physico-chemical changes on treated PALF/PVA composites compared to untreated PALF/PVA composites. The results from thermogravimetric analysis (TGA) showed that the introduction of untreated PALF into the composites enhanced the thermal stability of the composites. Progressive improvement of thermal stability was discovered by associating treated PALF with the composites. The treated PALF composites produced also improved mechanical properties with increasing fibre content. Differential scanning calorimetric (DSC) analyses showed no significant changes in melting temperatures upon incorporating untreated PALF into the PALF/PVA composites. The best improvement in tensile strength value was obtained for treated PALF composite having 3 wt% of fibre loading, with enhancements of about 11% and 54%, compared to untreated PALF composites and plain PVA matrix, respectively.

Effect of alkali treatment on novel natural fiber extracted from the stem of Lankaran acacia for polymer composite applications

Effect of alkali treatment on novel natural fiber extracted from the stem of Lankaran acacia for polymer composite applications

Effect of Alkali Treatment and Particle Size on Sound Absorption Coefficient of Particleboards Made from Oil Palm Frond

This study uses an experimental approach to illustrate the significance of particle size and alkali-treated on the sound absorption coefficient of oil palm frond (OPF) particleboard. Two variables were investigated: Particle size and one hour of NaOH treatment of oil palm frond. The particleboard was manufactured based on OPF material with 10% urea-formaldehyde as the binder and 1% NHCl4 as the hardener. The mixing of OPF with UF was pressed under hot-pressing of 9 tons at 140°C for 5 minutes to obtain OPF particleboard. 100 mm and 29 mm diameter of OPF particleboard were fabricated with three different particle sizes in the constant density of 0.4 g/cm3 and thickness of 10mm. Three particle sizes were fine, medium, and coarse particle sizes with a diameter of 0.2-0.6, 1-2, 2.4-4.8 mm, respectively. The SAC was determined using a two-microphone impedance tube following ASTM E 1050 at frequencies 50 to 6400 Hz. The single rate number, noise reduction coefficient (NRC), the mean of arithmetical values for the SAC at four-octave bands frequency (250, 500, 1000, and 2000), was determined. The data from experimental and calculation were obtained and investigated.

Effect of alkali treatment on cotton/bamboo fibres for application as a reinforcement material

The current study focuses on the creation of epoxy composites with cotton/bamboo woven fabric reinforcement. The effect of alkali treatment with varying (1, 2, and 3 wt.%) of NaOH on mechanical characteristics such as tensile, impact, flexural, compression, and interlaminar shear stress is explored and compared to those of the untreated cotton/bamboo fabric. The composites were made using a compression moulding process with four different fibre loadings (30, 35, 40, 45, and 50 wt.%). The mechanical characteristics of the composites were studied and their structure was evaluated by using a scanning electron microscope (SEM). The cotton/bamboo/epoxy composite with 2 wt.% NaOH at 45 wt.% fibre loading was found to have better mechanical properties when compared to the others.

Effect of alkali treatment on the friction coefficient of single coconut fiber

Effect of alkali treatment on the friction coefficient of single coconut fiber

Effects of alkali treatment on structural and functional properties of chickpea protein isolate and its interaction with gallic acid: To improve the physicochemical stability of water–in–oil emulsions

To expand the application of chickpea protein isolate (CPI) in water–in–oil (W/O) emulsion systems and to address its limitations in inhibiting lipid oxidation in W/O emulsions, alkali treatment was used to enhance the functional properties of CPI and to promote its combination with gallic acid (GA). The results showed a slight increase in the antioxidant activity of CPI upon pH 11 treatment, which was attributed to the exposure of sulfhydryl groups (3.39 μmol/g). The interfacial activity of CPI treated with pH 11 was enhanced (e.g., interfacial tension of 1.72 mN/m and interfacial adsorption of 93.20%). In addition, the alkali treatment promoted the covalent binding of CPI and GA, especially under mild alkaline conditions (pH 9, the binding equivalent was 13.12 mg/g protein). The results of amino acid and intrinsic fluorescence spectrum indicated that the binding sites for CPI and GA might include Met, Glu, His, Lys, Arg and Trp residues. The combination of CPI and GA further changed the structural and functional properties of CPI. When alkali–treated CPI and CPI–GA combinations were added to emulsions, the increase in physical stability was attributed to a reduction in droplet size and an increase in ζ–potential. In terms of chemical stability, the higher interfacial activity and the higher GA binding equivalent of CPI contributed to the higher accumulation of GA at the droplet interface. This ultimately improved the chemical stability of the W/O emulsion (57.03% and 61.34% reduction in primary and secondary oxidation products respectively). This work provides guidance on the application of interfacial engineering to modify proteins with high interfacial and low antioxidant activity and to improve the physicochemical stability of W/O emulsions.

The Effect of Alkali Treatment on the Cellulose Extracted from Rice Husk as Potential Resources of Biomass

Over the last few decades, the use of agro by-products as a biopolymer for various applications has attracted significant interest of researchers. Rice husk (RH) is one of the agro by-products produced abundantly worldwide and a great deal of studies in extracting and utilizing silica from RH have been reported but scarcely for its cellulose components. A specific study on the utilization of cellulose extracted from RH for the electrospinning process also remains unreported. Chemical pre-treatment seems to be the most crucial step which improves the elimination of the cementing components and exposing the cellulose for further applications. This study aimed to explore the potential of RH as a source of raw material to produce cellulose nanofiber. The cellulose was extracted by acid pre-treatment, alkaline treatment at varying sodium hydroxide (NaOH) concentrations, followed by bleaching treatment with sodium hypochlorite for complete removal of the amorphous region. The resulting cellulose was characterized and the main properties (morphology and sizes) of the extracted cellulose were made using scanning electron microscopy (SEM). The findings revealed the almost complete removal of the noncellulosic components for the subsequent production of electrospun cellulose nanofibers. Therefore, the output of the cellulose from this underutilized agro-waste has commercial application potential that can add value and be further utilized for the electrospinning process.

The Effect of Alkali Treatment on the Crystallinity, Thermal Stability, and Surface Roughness of Bamboo Fibers

The Effect of Alkali Treatment on the Crystallinity, Thermal Stability, and Surface Roughness of Bamboo Fibers

Effect of alkali treatment on novel natural fiber extracted from Himalayacalamus falconeri culms for polymer composite applications

Effect of alkali treatment on novel natural fiber extracted from Himalayacalamus falconeri culms for polymer composite applications