Journal Articles
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Item Morphological and thermal properties of maize fiber composites(Korean Fiber Society, 2012) Saravana Bavan, D.; Mohan Kumar, G.C.Maize stalk has become one of the major sources of fibers from the agricultural residues. Use of these fibers as a reinforcement in the polymer is described in this paper. The present work is focused on establishing the properties such as physical, chemical, morphological structure and thermal properties of maize stalk fiber using different characterization techniques. Simple hand layup method was followed for processing the composite material. Chemical treatments of fibers were carried out to study the interaction of fibers with the matrix. The results revealed that maize fibers can also be used as a traditional fiber as reinforcement in a natural fiber reinforced composite materials. © 2012 The Korean Fiber Society and Springer Science+Business Media Dordrecht.Item Tensile, impact, and vibration properties of coconut sheath/sisal hybrid composites: Effect of stacking sequence(SAGE Publications Ltd, 2014) Krishnasamy, K.S.; Siva, I.; Nagarajan, N.; Jeyaraj, P.; Winowlin Jappes, J.W.This work addresses the tensile, impact, and free vibration properties of sisal/coconut sheath fiber hybrid-reinforced unsaturated polyester composites. The hybrid composites are fabricated using a compression molding technique with varying stacking sequences under as-received or chemically treated conditions. The chemical treatments (alkali and tri-chloro vinyl silane) have shown better performance than untreated composites. Furthermore, the silane-treated composite shows enhanced static mechanical and free vibration properties for all stacking sequences relative to the other two cases. From the experimental results, the silane-treated coconut sheath/sisal/coconut sheath hybrid stack is found to be an optimum stacking sequence for better properties. Further, an encouraging damping factor value is also observed for the optimum stacking sequence. The failure mechanism of interfacial de-bonding between the fibers and the matrix is analyzed with the aid of scanning electron microscopy. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.Item Mechanical characterization of natural fiber intra-ply fabric polymer composites: Influence of chemical modifications(SAGE Publications Ltd info@sagepub.co.uk, 2017) RAJESH, M.; Jeyaraj, P.The influence of surface treatment (alkali, potassium permanganate, benzoyl chloride and silane) on the mechanical, dynamic mechanical and free vibration properties of intra-ply hybrid banana/jute woven fabric composite has been analyzed. Intra-ply woven fabrics are fabricated by keeping banana yarn in weft direction and jute yarn in warp direction of a basket-type woven fabric. Results reveal that the enhancement of tensile and flexural strengths of the composite due to the chemical treatment is marginal, except for the benzoyl chloride treatment. However, the chemical treatment results in better impact strength compared to the untreated composite. Tensile, flexural and impact strengths of the benzoyl chloride treatment increase by 10%, 30% and 50%, respectively, compared to untreated composite. It is evident from Fourier Transform-Infrared Spectra that benzoyl chloride treatment effectively removes the hemicellulose and lignin content. It is observed that benzoyl chloride and alkali treatment improves the dynamic mechanical characteristics. Experimental modal analysis carried out on intra-ply fabric composites reveals that benzoyl chloride treatment increases the natural frequency significantly compared to the untreated composite. © 2017, © The Author(s) 2017.Item Influence of particulate surface treatment on physical, mechanical, thermal, and dielectric behavior of epoxy/hexagonal boron nitride composites(John Wiley and Sons Inc. cs-journals@wiley.com, 2020) Agrawal, A.; Chandraker, S.Physical, mechanical, thermal, and dielectric behavior of surface modified hexagonal boron nitride (hBN) in epoxy matrix was investigated in this paper. Effective treatment of microsize boron nitride involved silane coupling agent, (?-aminopropyl)triethoxysilane such that the coating resulted from the treatment amounted to 2% of the weight of silane coupling agent of the treated BN. The present work revealed that the chemical treatment of BN surface could effectively enhance the adhesion between matrix and filler material. The dispersion and wettability of the BN powder in epoxy matrix after surface treatment were improved. These imparted improved physical and excellent mechanical and thermal properties to the developed material. The experimental study on thermal properties of fabricated composites indicated that incorporation of modified particles exhibits improved glass transition temperature. As filler loading increases, coefficient of thermal expansion of composite decreases which further decreases when treated filler were used. Further, appreciable improvement in thermal conductivity is obtained when treated hBN is used in place of untreated one. The dielectric properties are investigated for wide frequency range and filler content and found to be increased with hBN content and decrease with frequency enhancement. Furthermore, mechanical properties of such composites were also largely enhanced when treated fillers were used. With modified properties, the presently developed material is suitable for microelectronic applications. © 2019 Society of Plastics EngineersItem Reprocessed waste sunflower cooking oil as quenchant for heat treatment(Elsevier Ltd, 2020) Prathviraj, M.P.; Samuel, A.; Prabhu, K.N.The growing concern to minimize the use of petroleum derived mineral oil in heat treatment industries has led to the search for alternative eco-friendly quenchants. Although vegetable oils seem to be a viable option, the higher cost and inferior thermal and oxidation stability have limited their application in the heat treatment industry. The reuse of waste cooking oils for industrial heat treatment would not only make quenchants cost-efficient but also environment friendly. In this study, the cooling performance of waste sunflower cooking oil was assessed and compared with that of unused sunflower cooking and mineral oils. The waste sunflower oil was made suitable for quenching by cleaning and chemical treatment. The experiment to assess the suitability of reprocessed oil for quenching was conducted using an Inconel 600 standard probe according to ISO 9950 and ASTM D 6200 standards. The thermal history acquired while quenching of the probe was used to estimate the surface heat flux transients. The results indicated that the chemically treated waste sunflower cooking oil had a higher cooling performance than that of unused sunflower and the mineral oils. A good agreement was found between the heat flux transients and hardness data obtained with the quenched AISI 4140 steel probe. The simulation of temperature and hardness distribution indicated more uniformity along the length of the probe indicating more uniform cooling with chemically treated waste sunflower cooking oil. © 2020 Elsevier LtdItem Evaluation of Enzymatic and Chemical Treatments to Produce Oxalate Depleted Starch from a Novel Variety of Colocasia esculenta Grown in Joida, India(John Wiley and Sons Inc, 2022) Kizhakedathil, M.P.J.; Belur, P.D.; Wongsagonsup, R.; Suphantharika, M.; Agoo, E.M.G.; Janairo, J.I.B.This research aimed to study granular and molecular structures, physicochemical, and functional properties of the starch extracted from a novel, dasheen type of taro conserved, and cultivated by several generations of Kunabi tribes of Joida, Karnataka, India. Further, an enzymatic (oxalate oxidase) and chemical (phosphoric acid) treatment processes are evaluated for reducing total oxalate content in the starch extracted from the taro flour. The total oxalate content of the taro flour is found to be 2344 mg 100 g−1, and the starch yield is about 45% in all the methods. The oxalate oxidase (OxO) and phosphoric acid treatment reduced the total oxalate content by 98.37% and 98.03%, respectively. The residual oxalate content in the resultant starch is within the threshold limit (71 mg 100 g−1). The study of characteristic properties of enzyme-treated (ET), phosphoric acid-treated (PT), and native starch (NT) revealed minor changes in ET and PT compared to NT. © 2021 Wiley-VCH GmbHItem Compressive Characterization of Date Palm Leaf Fiber(Taylor and Francis Ltd., 2022) Nanda, J.; Das, S.N.; Mohapatra, A.In this present work, the surface of date palm leaf fiber has been modified by means of different chemical treatments. The thermal, morphological, mechanical, and water absorption characteristics of DPL fibers were investigated. The effect of the surface modifications of the DPL fibers was envisioned through the SEM micrographs, which shows the existence of voids and rough surfaces because of the elimination of lignin, wax, and pectin from the fiber. FTIR spectroscopy of DPL fibers was done, to check the effects of surface modifications on the fiber composition. XRD analysis confirms the improvement in crystallinity index of the surface-modified DPL fibers. The thermogravimetric analysis confirms augmentation in the thermal stability and tensile strength of the surface-modified fibers. The water absorptivity test conforms the reduction in the water absorption of the DPL fiber after surface modification. Furthermore, the DSC curve shows the temperature range for the moisture vaporization from fibers, fiber degradation, and the formation of char.key words-Natural fiber,Composite,Date palm leaf fiber,XRD,SEM,FTIR. © 2021 Taylor & Francis.Item Bearing ratio behaviour of sisal geotextile reinforced fly ash overlying clay(Taylor and Francis Ltd., 2025) Jena, S.; Khatri, V.N.; Nainegali, L.The paper examines the bearing ratio behaviour of sisal geotextile reinforced fly ash over clay. It also evaluates the effects of alkali treatment and emulsion coating of the geotextile on the bearing ratio at optimal placement depths. Results show that using one, two, and three layers of untreated geotextile increased the CBR by 19.6%, 55%, and 78% at different placement depths (1.5B, 1B, and 0.5B), where B is the plunger diameter. Alkali-treated and emulsion-coated geotextiles increased the CBR by 24.6% and 15.6%, respectively. However, soaking reduced the CBR by 76.6%, with the greatest decrease observed in triple-reinforced alkali-treated samples. Punching tests and morphological analyses supported the study outcomes. A numerical study of a pavement section, based on the experimental results, recommends sisal geotextile for rural roads using load equivalency factors and the structural number approach. © 2025 Informa UK Limited, trading as Taylor & Francis Group.