Alkali Treatment Conditions Research Articles

Regulation of Osteogenic and Angiogenic Markers in Alkali Treated Titanium for Hard Tissue Engineering Applications.

Titanium (Ti) and Ti alloys are of great interest in bone and dental tissue engineering applications due to their biocompatibility, corrosion resistance, and close mechanical properties to natural bone. However, the formation of fibrous tissue prevents osteointegration and results in implant loosening. Thus, physical and chemical methods are used to improve the surface properties of Ti. This study aimed to understand the role of alkali treatment conditions, including alkali medium concentration, temperature, rotation speed, and post-heat treatment. Our results showed that alkali treatment using 5 and 10 molar sodium hydroxide solution allows the formation of web-like microstructure. However, a higher concentration of 15 molar resulted in cracks along the surface. Interaction between the human fetal osteoblast cells (hfOBs) and Ti samples showed that heat treatment is necessary for increased cellular proliferation, which was not significantly different at later time points compared to the polished Ti. Alkali heat treatment did not induce inflammatory reactions at later time points. It showed an increase in vascular endothelial growth factor, osteoprotegerin/nuclear factor kappa-В ligand ratio, and osteocalcin expression, which is evidence for accelerated osteoblast cell maturation and bone remodeling in surface-modified samples. Together, these data show that alkali treatment using 5 or 10 molar of NaOH followed by heat treatment may have therapeutic effect and assist with bone tissue integration with Ti implant.

Optimization of Alkali Treatment Conditions of Ramie Fabrics Using Box–Behnken Method

Ramie is a widely used plant fiber for making textiles and reinforcement in biodegradable composites. Pretreating cellulosic fibers with alkali before producing composites is increasingly used to enhance adhesion with polymeric resin. In this work, response surface methodology (RSM) based on the Box-Behnken technique was utilized to investigate the impact of independent variables on ramie fabric characteristics and determine the optimal treatment condition. The impact of alkali concentration, treatment time, and temperature on the breaking load and elongation at break of woven ramie fabrics were evaluated using Design-Expert software, which established the design matrix and analyzed the experimental data employing numerical and graphical optimization methods. Moreover, the impact of alkali treatment conditions on the surface morphology, structural change of ramie fabrics, and thermal properties was investigated. Based on the analysis of variance (ANOVA) results, the suggested quadratic models can adequately predict the breaking load and elongation at break of the ramie woven fabrics within the range of conditions applied in this investigation. The RSM revealed that an alkali concentration of 6.12%, a treatment time of 30 min, and a temperature of 39.13°C resulted in an optimum treatment condition with a breaking load of 518.28 N and elongation at break of 23.36%.

Treatment of As(III)-contaminated food waste using alkali treatment and its potential application for methylene blue removal from aqueous solutions

Conventional methods for managing food waste become ineffective when the waste is contaminated with toxic chemicals due to the risk of further contamination. To address this issue, this study proposes an alkali pre-treatment approach to decontaminate processed food waste containing As(III) and repurpose it as an adsorbent for treating wastewater. The study investigates the effects of different alkali treatment conditions, (concentration, treatment time, and temperature), on the decontamination of As(III) and its impact on the adsorption behavior of methylene blue. Experimental results demonstrate that treating the material with 0.8 M NaOH at 60 °C for 4 h effectively eliminates As(III), achieving a remarkable removal rate of 99.8 %. Characterization results revealed that the alkali-treated material exhibits desirable properties, including increased carboxylation, improved thermal stability, reduced crystallinity, and a significantly enlarged specific surface area (66.03 %) compared to the original contaminated food waste. The alkali-treated waste demonstrates good adsorption capacity towards methylene blue, with a maximum adsorption capacity of 534.6 mg/g achieved at pH 8.0, 40 g/L adsorbent dose, 10 h shaking time, and 20 °C. The Temkin (R2 = 0.978) and intraparticle diffusion models effectively describe the adsorption data. Notably, the adsorbent demonstrates excellent reusability, as it can be utilized for at least 4 cycles of adsorption-desorption without a significant reduction in methylene blue removal efficiency (only a 5.2 % decrease), highlighting its practical potential. The results strongly indicate that alkali pre-treatment represents a simple and efficient method for eliminating As contamination from food waste while concurrently producing an effective adsorbent for removing dyes from aqueous solutions.

Quantitative Extraction of p-Coumaric Acid and Ferulic Acid in Different Gramineous Materials and Structural Changes of Residual Alkali Lignin

Ferulic acid (FA) and p-coumaric acid (pCA) in bagasse, wheat straw, corn straw, and corncob were extracted by alkaline hydrolysis and characterized by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). It was found that the FA and most of the pCA in gramineous biomass could be dissociated and released after being treated with 1 M NaOH at 100°C for 4 h. The yields of pCA/FA in bagasse, wheat straw, corn straw, and corncob determined by GC-FID are 39.8/11.5, 13.7/11.0, 28.0/11.0, and 35.1/14.5 mg/g, respectively. The raw materials and the treated solid residues were characterized by gel-state 2D Heteronuclear Single Quantum Coherence Nuclear Magnetic Resonance (2D HSQC NMR). It was found that only a small amount of lignin was detected in the residue after alkali treatment, indicating that the alkali treatment conditions can effectively cleave the FA and pCA. Additionally, the lignin in the alkali solution was recovered and characterized by 2D HSQC NMR. The FA was not able to be detected by NMR, whereas a small amount of pCA remained in the alkali lignin. This study reveals the structural change of residual lignins during the quantitative isolation of FA and pCA, which is essential for the selective isolation of pCA/FA and valorization of residual alkali lignin.

Alkali pre-treatment of jute yarns for reinforcement in epoxy composites

In this study, alkali treatment of jute yarns of different counts has been carried out for their subsequent application as reinforcing material in composite. The alkali treatment conditions have been optimised to improve the interaction between fibrous material and matrix. It is observed that the responses of different yarns are different. Other than the types of fibre, the structure of yarn has significant influence on the responses. The maximum tenacity is obtained at a lower alkali concentration for the lower count (4 lb/spyndle) and at a higher alkali concentration for the highest count (12 lb/spyndle). While for the medium counts of 6 lb/spyndle, 8lb/spyndle, and 10 lb/spyndle, maximum tenacity is obtained at 10% NaOH concentration. XRD, FTIR, and SEM studies authenticate the partial delignification of the jute yarn and increase in the crystallinity after the alkali treatment.

Influence of glucan on physicochemical and rheology properties of chitin nanofibers prepared from Shiitake stipes

Procedures for chitin nanofibers extraction from mushroom significantly modify their structure and physicochemical properties, through disintegration and surface oxidation of glucan residue, as well as surface deacetylation of chitin. Here, four kinds of chitin-glucan nanofibers (CGNF) were isolated form Shiitake stipes via different alkali treatment conditions, wherein glucan content ranged from 6.4 % to 46.8 %. Observations with transmission electron microscopy showed that CGNFs possessed average widths with 5.1 ± 1.2 to 7.1 ± 1.5 nm. The glucan showed a negative effect on the crystal index and thermal stability of CGNFs. A strong positive correlation was observed between glucan residues and zeta potential value. The phenomenon about the increase of viscosity, yield stress and elastic modulus upon glucan decrease was discussed. Overall, the residual glucan offers fungi-derived chitin nanomaterials a diversity of material properties and tuning its content is a feasible approach for customize nano chitin fibers used in nutraceutical and food industry.

Alkali-mediated dissolution-recrystallization strategy for in situ construction of a BiVO4/Bi25VO40 heterojunction with promoted interfacial charge transfer: Formation mechanism and photocatalytic tetracycline degradation studies

Constructing a heterojunction between semiconductors with identical elements constitutes an intimate contact that can greatly accelerate the charge carrier transfer and separation. Herein, a novel BiVO4/Bi25VO40 heterojunction was designed by the in situ conversion of pre-prepared BiVO4 in alkaline conditions. We investigated the formation process of BiVO4/Bi25VO40 heterojunctions by XRD structural refinement, Raman spectra, morphology characterization, and density functional theory calculations, and found that heterojunction formation occurred through a dissolution–recrystallization process, in which monoclinic BiVO4 decahedrons were first etched by alkali solution on the preferential {0 1 0} face and then transformed into cubic Bi25VO40. By adjusting the alkali treatment conditions, the phase composition of the heterojunction can be precisely modulated with BiVO4 decreasing and Bi25VO40 increasing in content as the synthesis time was extended. Benefiting from the in situ conversion strategy and matched band structure, the intimate type II heterojunction with close interfacial contact was formed between BiVO4 and Bi25VO40, leading to facilitated charge transfer with spatial separation of carriers and significantly enhanced photocatalytic performance in the probe reaction of tetracycline (TC) degradation. The active species responsible for TC removal were explored by radical trapping tests and ESR spectra, and the photodegradation pathways were proposed on the basis of HPLC-MS. This work provides deeper insight on the rational design of highly efficient semiconductor photocatalysts by precise regulation of the crystal growth process for solar energy conversion.

Cellulose Fibre from Schinus molle and Its Characterization

The exploitation of biomass represents a major environmental challenge related to the protection of the environment and the progressive exhaust of fossil resources. In this perspective, the main objective of this work is the extraction and the characterization of natural lignocellulosic fibers from the Schinus molle. The cellulose fibre extraction was investigated employing conditions of alkali treatment. After the alkaline steps, a bleaching treatment was done and let to a yield about 45% pure cellulose. The identification of the chemical composition of Schinus molle reveals that this raw material contains a high level of biopolymers with a cellulose rate of 53.2%. Extracted cellulose fibers have been characterized by several techniques such as scanning electron microscopy, Fourier transform infrared, X-ray diffraction, Morfi, and by the determination of their degree of polymerization. FT-IR results confirm the purity of the cellulosic fibers, and XRD analysis reveals that the crystallinity increases after the delignification and bleaching treatments.

Alkali pretreatment effects on acid leaching recovery of rare earth elements from coal waste of the Western Kentucky No. 13 and Fire Clay seams

The recovery of rare earth elements (REEs) from the Western Kentucky No. 13 and Fire Clay coal wastes was enhanced by alkali pretreatment with concentrated NaOH solutions. The enhancements in the recovery of light REEs (LREEs) are more significant than those of heavy REEs (HREEs). For example, after treating with 5 M NaOH at 90 °C, the recovery of LREEs from the Western Kentucky No. 13 coal waste increased from 26% to 71%, while the recovery of HREEs only increased from 29% to 41%. Based on mineralogical studies through scanning electron microscopy-energy dispersive X-ray spectroscopy and X-ray diffraction analyses, two mechanisms were proposed to explain the positive effect of alkali pretreatment: (1) decomposition of rare earth minerals (primarily crandallite-group minerals) during the alkali pretreatment, and (2) liberation of encapsulated REE-bearing particles due to the enhanced dissolution of clay minerals. The more significant enhancements in the recovery of LREEs were explained by the fact that the REEs comprised in the crandallite-group minerals were mainly LREEs. Compared with zircon, monazite, and xenotime, alkali pretreatment with 5 M NaOH led to a more significant decomposition of crandallite-group minerals. In order to further increase the recovery of REEs, particularly HREEs, harsher alkali treatment conditions are required.

Effect of Different Pretreatment of Birch Sawdust on the Production of Active Polysaccharides by Inonotus obliquus Under Submerged Fermentation and Its Structural Mechanism.

This study examined the effects of different pretreatments of birch sawdust on the production and activity of polysaccharides by Inonotus obliquus, and in order to explore the mechanism, structural characterization and analysis were carried out. The result clearly indicated that alkali treatment, ozone treatment, and alkali combined with ozone treatment of birch sawdust could be all helpful for the production of active polysaccharide by I. obliquus. Among four pretreatment groups, birch sawdust treated with alkali showed the highest increase in the exo-polysaccharide content (39.90%) and the inhibition rate of α-glucosidase (80.78%) within 11 days by the mycelium of I. obliquus through deep fermentation, in comparison to water-washed birch sawdust. Through a single-factor analysis and orthogonal experimental design, the optimum alkali treatment condition was as follows: NaOH concentration 1%, temperature 60 °C, and time 3 h. Moreover, the structural characteristics of pretreated birch sawdust with the optimum alkali treatment condition before and after fermentation by the mycelium of I. obliquus was performed by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electronic microscopy. The results showed that alkali treatment destroyed the lignin structure of birch sawdust, exposed the cellulose in the amorphous area, reduced the crystallinity of lignocellulose, and damaged the surface structure of birch sawdust, which had a further damage and a greater degradation degree of birch sawdust after fermentation, indicating that alkali pretreatment was beneficial for utilization of birch sawdust by I. obliquus.

Effect of varied fiber alkali treatments on the tensile strength of Ampelocissus cavicaulis reinforced polyester composites: Prediction, optimization, uncertainty and sensitivity analysis

Studies on modeling and optimization of alkali treatment, investigation of experimental uncertainty and sensitivity analysis of alkali treatment factors of natural fibers are important to effective natural fiber reinforced polymer composite development. In this contribution, response surface methodology (RSM) was employed to investigate and optimize the effect of varied treatment factors (sodium hydroxide concentration (NaOH) and soaking time (ST)) of the alkali treatment of Ampelocissus cavicaulis natural fiber (ACNF) on the tensile strength (TS) of alkali treated ACNF reinforced polyester composite. RSM and multi gene genetic programming (MGGP) were comparatively employed to model the alkali treatment. The best model was applied in Oracle Crystal Ball (OCB) to investigate the uncertainty of the treatment results and sensitivity of the treatment factors. Results showed that increased NaOH and ST increased the TS of the alkali treated ACNF reinforced polyester composite up to 28.3500 MPa before TS decreased. The coefficient of determination (R 2 ) and root mean square error (RMSE) of RSM model were 0.8920 and 0.6528 while that of MGGP were 0.9144 and 0.5812. The optimum alkali treatment established by RSM was 6.23% of NaOH at 41.99 h of ST to give a TS of 28.1800 MPa with a desirability of 0.9700. The TS of the validated optimum alkali treatment condition was 28.2200 MPa. The certainty of the experimental results was 71.2580%. TS was 13.8000% sensitive to NaOH and 86.2000% sensitive to ST. This work is useful for effective polymer composite materials production to reduce the enormous material and energy losses that usually accompany the process. • RSM study on the effect of fiber alkali treatment on tensile property of reinforced polymer composite. • RSM modeling and optimization of the effect of fiber alkali treatment on tensile property of reinforced polymer composite. • RSM and MGGP comparative modeling of the effect of natural fiber alkali treatment on tensile property of reinforced composite. • Sensitivity analysis of the effect of fiber alkali treatment on the tensile property of reinforced polymer composites.

Deacidification of Microalgal Oil with Alkaline Microcrystalline Cellulose.

Microalgal oil is considered a promising candidate for edible oils. However, investigation of the refining processes of microalgal oil has been limited, especially deacidification. In this work, microcrystalline cellulose (MCC) was pretreated using different methods and utilized for the first time in the deacidification of microalgal oil. Detection results from FTIR and XRD indicated alkali pretreatment had a significant effect on the structure of MCC. Some inter- and intramolecular hydrogen bonds in AMCC (alkali-pretreated MCC) were destroyed, and crystallinity index of cellulose decreased, which increased its adsorption capacity and the reaction of OH groups with free fatty acids. Some NaOH was adsorbed into AMCC through cellulose swelling, which also contributed to deacidification. The interaction with oil was also improved with many cracks and voids on the surface of AMCC. AMCC could reduce the acid value to about 2mgKOH/g. Comparatively, original MCC and MCC pretreated with microwave or ultrasound did not exhibit the ability to deacidify. Furthermore, the conditions of alkali treatment were optimized. Treatment with 20% NaOH for 20min was optimal. Compared with other adsorbents, such as sodium silicate and chitosan treated with alkali and resin, only AMCC could effectively reduce acid value while maintaining high lipid recovery. Therefore, AMCC was considered a better adsorbent for the deacidification of microalgal oil.

Surface modification of nanotubular anodized Ti–7.5Mo alloy using NaOH treatment for biomedical application

In this study, NaOH/heat treated nanotube layers formed on anodized Ti–7.5Mo were subjected to a variety of alkali treatment conditions to obtain improved apatite forming ability. The as-fabricated nanotubes formed on Ti–7.5Mo by anodization at 10 V in NH4F/NaCl electrolyte were amorphous. After 3 h of heat treatment at 450°C, these nanotubes crystallized into the anatase phase. The heat-treated nanotube arrays were mainly composed of TiO2, MoO2, MoO3, and Mo2O5. However, the intensity of the Mo 3d spectra in the Ti–7.5Mo surface was indiscernible after 5 M of NaOH treatment; the peak assigned to Na was detected after the alkali treatment. Anodized Ti–7.5Mo is more bioactive and has a nanoscale porous network structure when it is chemically treated with a NaOH solution. These properties are absent on anodized surfaces that are not NaOH treated. After the 5 M NaOH-treated Ti–7.5Mo specimen was soaked in simulated body fluid for 6 h or less, nano-sized apatite particles completely covered the entire porous network surface. After immersion in simulated body fluid for 14 days, the thickness of the Ca-P layer on the anodized and either 0.5 or 5 M NaOH-treated Ti–7.5Mo surface was about 418 nm and 439 nm, respectively. However, the thickness of the Ca-P layer on the anodized Ti–7.5Mo surface that was not subjected to alkali-treatment was approximately 415 nm. The preliminary in vitro cell culturing results showed that the anodized and NaOH- and heat-treated Ti–7.5Mo alloys not only had good biocompatibility, but also supported cell adhesion.

DEVELOPMENT OF TECHNOLOGY FOR PRODUCTION OF DISSOLVING WOOD PULP

The work is devoted to the study of possibility and expediency of ECF bleaching for semi-chemical pulp with production of dissolving pulp, which is very popular in Russia and in the world. Production of dissolving wood pulp is important to replace cotton pulp obtained from imported raw materials.
 The conditions of bleaching and alkali treatment of sulfite pulp are investigated. CA dissolving pulp grade P was produced. To this end, new environmentally reliable short bleaching and alkali treatment schemes of sulfite pulp have been developed using only two oxidizing reagents: hydrogen peroxide and sodium chlorite. The bleaching schemes are based on the ECF technology developed earlier by the authors.
 Bleached dissolving pulp CA grade P was obtained according to all proposed schemes, including the shortened scheme Pa–E–Ch1–HAT–Ch2–A; pulp with increased yield was obtained due to good selectivity of the used chemicals under the developed conditions of delignification and bleaching, which contributes to the economy of wood. The possibility of obtaining pulp for viscose according to the above scheme is also shown.
 The results of studies have shown the possibility of obtaining wood pulp CA grade P from these raw materials by TCF technology with the use for delignification and bleaching (after alkali treatment) of hydrogen peroxide in an acidic and traditional alkaline medium, respectively.

Structural Features of Lignin Fractionated From Industrial Furfural Residue Using Alkaline Cooking Technology and Its Antioxidant Performance

： For furfural industry, industrial furfural residue as the solid waste was generated from the production of furfural, and is rich in cellulose and lignin with a certain degree of degradation because of strong acid (H2SO4) as catalyst. In this work, alkali cooking technology was applied to extract lignin from industrial furfural residue to explore the new route of industrial application. The effect of different alkali treatment conditions on the chemical structure of lignin was studied. And the effects of different alkali treatment conditions on the composition and chemical structure of the residue were studied by NREL, 13 C NMR and ATR. The results showed that obtained lignin contained abundant guaiacyl (G), syringyl (S) and p-hydroxyphenyl (H) structural units, among which G-type lignin structural units accounted for the main proportion. The extracted lignin samples were rich in hydroxyl, and the highest content of hydroxyl was 4.02 mM/g under the condition of alkali cooking (135 ℃-0.35 M). Oxidize resistance test showed obtained lignin samples had high inhibition effect on DPPH. Moreover, the relative content of cellulose in the solid residue decreased and the relative content of lignin increased significantly because of the lignin-like substance formation by partial degradation and carbonization of cellulose under high-severity cooking treatment. This alkali cooking technology was suitable for extracting lignin from furfural residue without significant change in lignin structure, which have the promising application as potential antioxidants in food and cosmetics.

Tensile Properties of Single Cellulosic Bamboo Fiber (Gigantochloa Scortechinii) Using Response Surface Methodology

ABSTRACT Gigantochloa scortechinii is one of the most well-known bamboo species in Malaysia because of its advantageous physical, morphological and strength properties. This study presented the effect of alkali treatment conditions of single cellulosic bamboo strips fiber following tensile test and optimized the parameters through response surface methodology based on central composite design. Bamboo strips fiber was treated under various alkali concentrations of 2, 4, 6 and 8 wt.% and soaking times of 1, 3, 6, 12, 18 and 24 h. Results showed that the optimum tensile strength at 4 wt.% alkali concentration and 12 h soaking time was improved by 28% compared with water retting condition. The design-Expert software was used to optimize the tensile properties of single cellulosic bamboo strips fiber. The effect of two independent variables, namely, alkali concentration and soaking time, on the optimized tensile properties of a single cellulosic bamboo strips fiber was investigated. Results showed acceptable R2 and high R2 Adj correlation coefficients for tensile strength, reaching 0.6926 and 0.9575, respectively. The high R2 and R2 Adj correlation coefficients for tensile modulus reached 0.9376 and 0.8931, respectively. Overall results showed that the confirmatory experiments show that the error between predicted and actual values does not exceed 5%. thus, the model can be effectively used to predict tensile properties.

Potential of alkali treated cornhusk film as reinforcement for epoxy laminate composites

This work is aimed to explore the potential of cornhusk film (CHF) as reinforcement in the epoxy matrix. The novelty of this work is to develop a laminate composite using alkali treated cornhusk film as it is for reinforcement. Previous reported researches based on cornhusk are primarily focused on production of ethanol from the bio waste or studies related to extraction of fibres from the cornhusk and its subsequent use as the reinforcing agent in composites. Importance of the present work also includes optimization of alkali treatment conditions of CHF in order to achieve better CHF-epoxy interphase and the respective composite properties. Characterization of CHF is carried out by XRD, FTIR, SEM and mechanical properties. Increase in crystallinity and reduction in crystal size of CHF is observed after alkali treatment. XRD and FTIR results reveal that treated CHF is Iβ (monoclinic) dominant cellulose. FTIR spectra and SEM images confirm the partial delignification of CHF after alkali treatment. SEM of the fractured surface of composite exhibits improved interphase between matrix and reinforcement. DMA test shows promising result for CHF reinforced composites.

The Effect of Extraction Conditions on Chemical and Thermal Characteristics of Kappa-Carrageenan Extracted fromHypnea bryoides

Hypnea bryoidescollected from the Arabian Sea on the southern coast of Oman was investigated forκ-carrageenan optimal extraction conditions. The effects of different conditions of alkali treatment (4, 6, and 8% w/v NaOH), temperatures (70, 75, and 80°C), and time (2, 2.75, 3.5 hours) on carrageenan yield and chemical and thermal properties were evaluated. Yield was significantly affected by alkaline concentration and temperature, with highest value of 26.74 ± 5.01%. Molecular weights of the extracted carrageenan were significantly reduced by increased temperatures and ranged from 5.95 ± 0.49 × 105 Da to 13.90 ± 0.14 × 105. FTIR showed that samples under all extraction conditions were similar and confirmed the presence ofκ-carrageenan with no traces ofμ-precursor. Sulfate content was also significantly reduced by alkaline concentration (from 4% to 6%) and ranged from 7.62 ± 5.52% to 17.02 ± 0.14. Thermal properties showed more sensitivity towards temperature and alkaline strength parameter than time. In addition, melting and gelling temperatures were significantly correlated with the molecular weight, but not sulfate content. In conclusion, mild extraction conditions were found to be more efficient in introducing the intended structural modification while getting the highest yield and quality.

Alkali extraction of rice residue protein isolates: Effects of alkali treatment conditions on lysinoalanine formation and structural characterization of lysinoalanine-containing protein

The influence of alkali extraction conditions on the formation of lysinoalanine (LAL) and the structural characterization of lysinoalanine-containing protein in rice residue protein isolates (RRPI) were explored in this study. It was found that LAL content increased from 0.256 to 13.079 g/kg as NaOH concentration increased from 0.03 to 0.09 M and then decreased to 1.541 g/kg at 0.13 M NaOH. The extraction temperature and time were found to have a positive correlation with LAL content. The highest LAL content (25.679 g/kg) was observed with alkali extraction using 0.09 M NaOH at 75 °C for 120 min. The comparative structural analysis results showed that alkali treatment could degrade cystine, lysine, threonine and arginine to generate LAL; increasing alkali content would cause variations in secondary structure and micropore appearance on the surface of lysinoalanine-containing protein, whereas increasing alkali treatment temperature and time could enlarge the surface particle size of the protein.

Optimization of Alkali Treatment Condition on Tensile Properties of Kenaf Reinforced Polyester Composite Using Response Surface Method

The interface bonding from the chemical treatment of the reinforced fibers can be seen as a great factor for mechanical properties on fiber composite. The alkali treatment serves as a method to increases the surface roughness that resulting in better mechanical interlocking and increases the amount of cellulose exposed on the fiber surface. The optimize condition of the alkali treatment on the tensile strength were investigated using response surface method (RSM). The kenaf fiber are treated with different concentration of alkali treatment, soaking time and temperature. The fiber composite was tested using ASTM D638 tensile test to determine the tensile strength. The highest average reading of kenaf reinforced composite is 26.37MPa from the highest percentage of volume fraction which is 25%. The Analysis of variance (ANOVA) was conducted using full quadratic term at the beginning of response surface methodology analysis work. From the response surface plot, the optimum composite tensile strength by setting the immersion temperature ranging at 30°C to 80°C and alkali concentration of 6% setting. The values of experimental tensile strength can be used on light weight constructional applications, auto-industrial, and many customary products.