Faculty Publications

Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736

Publications by NITK Faculty

Browse

Search Results

Now showing 1 - 4 of 4
  • Item
    Interparticle interactions and lacunarity of mechano-chemically activated fly ash
    (Elsevier, 2015) Patil, A.G.; Shanmugharaj, A.M.; Anandhan, S.
    A class F fly ash was subjected to high-energy ball milling-induced mechano-chemical activation aided by a surfactant. The resultant nanostructured fly ash was characterized by various techniques. X-ray fluorescence results showed that the amount of iron oxide was reduced from 4.39% to 2.75% after pre-treatment of fly ash by magnetic separation. Ethyl acetate as the milling medium, a ball to powder ratio of 12:1 and 2wt% of surfactant reduced the average particle size of fly ash to 329nm and led to a specific surface area of 8.73m2/g. The decrease in crystallite size of mechano-chemically activated fly ash was confirmed from a reduction in peak intensity with a broadened amorphous phase by X-ray diffraction studies. X-ray photoelectron spectroscopic characterization illustrated that peak area of major elements (O, Si and Al) increased after milling. Morphological and FTIR studies revealed that the smooth and inert surface of the fly ash was converted to a rough and more reactive one after mechano-chemical activation. The surface modification of fly ash with the surfactant was determined from FTIR spectroscopy. Also, a fractal approach was used to characterize the lacunarity of the agglomerates in the nanostructured fly ash. © 2014 Elsevier B.V.
  • Item
    Influence of planetary ball milling parameters on the mechano-chemical activation of fly ash
    (Elsevier, 2015) Patil, A.G.; Anandhan, S.
    This study illustrates the design of statistical analysis by Taguchi methodology to obtain nanostructured fly ash by planetary ball milling. An orthogonal array and analysis of variance were employed to analyze the effect of milling parameters. A class-F fly ash was subjected to planetary ball milling induced mechano-chemical activation aided by a surfactant. Ball milling parameters, such as ball-to-powder weight ratio, type and quantity of surfactant and type of medium were varied as guided by the Taguchi design. The nanostructured fly ash was characterized by dynamic light scattering, BET surface area analysis, X-ray diffraction, FTIR spectroscopy, scanning electron microscopy, field emission scanning electron microscopy and transmission electron microscopy. The ball-to-powder weight ratio and the surfactant type are the major influencing factors on lower crystallite size and average particle size and higher specific surface area. The surface modification of fly ash was confirmed by FTIR spectroscopy. The nano fly ash produced by this method has a wide application potential in polymer industries as reinforcement in composites. © 2015 Elsevier B.V.
  • Item
    Nanostructured Fly Ash as Reinforcement in a Plastomer-Based Composite: A New Strategy in Value Addition to Thermal Power Station Fly Ash
    (Springer Netherlands, 2016) Patil, A.G.; Mahendran, A.; Anandhan, S.
    Class-F fly ash (FA) from a coal-fired thermal power station was subjected to high energy ball milling-induced mechanochemical activation aided by a surfactant. Subsequently, ethylene-octene copolymer/mechanochemically activated FA (EOC/MCA-FA) composites were prepared by solution casting. The surface modification of FA was confirmed from contact angle measurements and FTIR spectroscopy, which accounts for a good interaction between MCA-FA and the polymer matrix. X-ray diffraction reveals that the crystallite size of quartz phase present in FA got reduced, while the relative lattice strain on it increased during milling. Morphological studies revealed that interfacial adhesion between the polymer and MCA-FA is good and this accounts for the improvement in mechanical properties of the composites even at the minimum filler loading. Flame retardance of the matrix polymer is improved by the addition of either fresh FA or MCA-FA. The results imply that FA is a valuable reinforcing filler for ethylene-octene copolymer and its mechanochemical activation is an effective strategy for its future use. © 2014, Springer Science+Business Media Dordrecht.
  • Item
    Characterization of composites based on biodegradable poly(vinyl alcohol) and nanostructured fly ash with an emphasis on polymer-filler interaction
    (SAGE Publications Ltd info@sagepub.co.uk, 2016) Patil, A.G.; SelvaKumar, M.; Anandhan, S.
    A thermal power station fly ash (FA) was mechanochemically activated by high-energy ball milling that yielded nanostructured FA. This nanostructured FA was incorporated into biodegradable poly(vinyl alcohol) (PVA) matrix by solution mixing and ultrasonication. Transmission electron micrographs revealed that the smooth spherical particles of FA were changed into irregular and rough ones; in addition, the particle size of FA was reduced to a few hundred nanometers, and its specific surface area value increased after the high-energy milling process. All these factors, in turn, led to a thermodynamically favorable interaction between the mechanochemically activated FA and PVA as evidenced by Fourier transform infrared spectroscopy. The incorporation of a very small amount of the nanostructured FA led to an increase in crystallinity of the polymer matrix. The glass transition temperature of the PVA matrix increased by about 18°C when 5 wt% of the nanostructured FA was used as the reinforcement. © The Author(s) 2014.