Faculty Publications

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    Modeling and optimization of thermally excited carbon black and polymer composite actuator
    (Elsevier Ltd, 2020) Hiremath, H.; Kulkarni, S.M.
    As of late, actuators in view carbon black, carbon nanotube and graphene were shown in the extraordinary potential application in the field of drug delivery system, relay switches, robotics, energy harvesting and so on. Now a day electro-thermal and photo-thermal driven actuator based on polymer composite show larger actuation compare to the traditional thermal actuator. Though, the impact of structural dimensions and material parameters on the actuator execution ought to be investigated further. Since it is a critical point in the design and fabrications of the high-performance actuator In the present work, finite element (FE) analysis is adopted to simulate the thermally driven bilayer actuator and investigated the performance based on carbon black and polymer composite. Thus, the computational method is carried out to design and optimize the geometry and material parameters such as thickness, the coefficient of thermal expansion and so on. FE simulation results demonstrate that each layer thickness of the actuator has an important role in curvature deformation. A maximum curvature is obtained of 8.9 m-1 by simulation, which is a decent expected value in light of the geometry and material. Furthermore, a larger change in temperature and CTE between two layers additionally predicts the more prominent bending curvature. Consequently, this investigation is relied upon to give a theoretical baseline to plan and fabrication of CB based thermal actuator for a greater actuation performance. © 2018 Elsevier Ltd.
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    Analytical solutions using a higher order refined computational model with 12 degrees of freedom for the free vibration analysis of antisymmetric angle-ply plates
    (2008) Swaminathan, K.; Patil, S.S.
    Analytical formulations and solutions to the natural frequency analysis of simply supported antisymmetric angle-ply composite and sandwich plates hitherto not reported in the literature based on a higher order refined computational model with 12 degrees of freedom already reported in the literature are presented. The theoretical model presented herein incorporates laminate deformations which account for the effects of transverse shear deformation, transverse normal strain/stress and a nonlinear variation of in-plane displacements with respect to the thickness coordinate thus modelling the warping of transverse cross sections more accurately and eliminating the need for shear correction coefficients. In addition, another higher order computational model with five degrees of freedom already available in the literature is also considered for comparison. The equations of motion are obtained using Hamilton's principle. Solutions are obtained in closed-form using Navier's technique by solving the eigenvalue equation. Plates with varying slenderness ratios, number of layers, degrees of anisotropy, edge ratios and thickness of core to thickness of face sheet ratios are considered for analysis. Numerical results with real properties using above two computational models are presented and compared for the free vibration analysis of multilayer antisymmetric angle-ply composite and sandwich plates, which will serve as a benchmark for future investigations. © 2007 Elsevier Ltd. All rights reserved.
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    New manufacturing process of carbon-carbon composites and their mechanical properties
    (2011) Naik, P.S.; Surendranathan
    This paper presents the synthesizing of carbon-carbon (CC) composites by preformed yarn (PY) method, by varying the percentage of carbon fiber volume. The PY used is carbon fiber bundle surrounded by coke and pitch which is enclosed in nylon-6. Three types of samples with fiber weight fractions of 30%, 40% and 50% respectively, are fabricated and tested. In each case, the PY is chopped and filled into a die of required shape and hot pressed at 600°C to get the carbonized composite. To obtain the graphitic structure, the specimen is heat treated at 1800°C followed by soaking for two hours. Further, one cycle pitch impregnation is done by hot isostatic pressing, to eliminate the voids. The characteristics such as hardness, compressive strength and creep, are studied. It is observed that, as the carbon fiber percentage increases the properties also improved, provided sintering is done at fairly higher temperatures. The superiority of the new class of CC composites made by the proposed PY technique over those obtained by the conventional methods is also demonstrated. © 2011 CAFET-INNOVA TECHNICAL SOCIETY.
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    Role of nickel filler on friction and dry sliding wear behavior of bismaleimide nanocomposite
    (2011) Kurahatti, R.V.; Surendranathan, A.O.; Srivastava, S.; Singh, N.; Ramesh Kumar, A.V.; Kori, S.A.
    Nano-sized metal particles filled polymer composites are finding numerous tribological applications in recent years. In the present work, the matrix properties were investigated by introducing nickel (Ni) nanoparticles (60-100 nm, weight fractions of 0.5-10 %) into a bismaleimide (BMI) resin. The influence of these particles on the microhardness, friction and dry sliding wear behavior were measured using microhardness tester, pin-ondisc wear set up. The experimental results indicated that the coefficient of friction and the specific wear rate (SWR) of BMI resin can be reduced at rather low weight fraction of Ni particles. The lowest SWR of 9 ×10 -6 mm 3/Nm (i.e. 50% lower than the value of neat BMI) was observed for the nanocomposite with Ni weight fraction of 1%. The incorporation of Ni particles leads to an increased hardness of BMI and the wear performance of the composites shows good correlation with the hardness. The results have been supplemented with scanning electron micrographs to help understand the possible wear mechanisms. © 2011 CAFET-INNOVA TECHNICAL SOCIETY.
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    Synthesis, characterization and desalination study of novel PSAB and mPSAB blend membranes with Polysulfone (PSf)
    (2012) Padaki, M.; Isloor, A.M.; A.F., A.F.; Abdullah, M.S.
    The present paper describes the synthesis of poly sulphonyl amino benzamide (PSAB) and methyalated poly sulphonyl amino benzamide (mPSAB) polymer, using terephthalic acid chloride and substituted 4-amino-1-benzensulphonmide in N-methyl-. 2-pyrrolidone. Polymers were characterized by FT-IR, NMR and GPC. Polysulfone composite membranes were prepared using these novel poymers by DIPS (Diffusion Induced Phase Seperation) method. These composite membranes are useful for water purification with special emphasis on sea water desalination. Newly prepared membranes were studied for salt rejection, water flux, molecular weight cut off by PEG solution, effect of the pH on water swelling and salt rejection and flux decline was also studied. 30 to 70% of the salt rejection was observed in all membranes. Effect of the dilution on salt rejection was studied using different concentration of NaCl solution varying from 1000. ppm to 3500. ppm. All the membranes showed 80% rejection for PEG having 1000. Da molecular weight. Contact angle and water swelling was measured to determine hydrophilicity of the membrane. Water swelling and salt rejection in different pH was also studied. © 2012 Elsevier B.V.
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    Preparation and characterization of sulfonated polysulfone and N-phthloyl chitosan blend composite cation-exchange membrane for desalination
    (2012) Padaki, M.; Isloor, A.M.; Wanichapichart, P.; A.F., A.F.
    Sulfonated polysulfone (sPSf) was prepared and used as a polymer matrix for cation-exchange membranes (CEM). The sulfonation reaction was carried out at room temperature and the degree of sulfonation was calculated by titration method. Blend composite membranes were prepared using different ratios of sPSf and modified chitosan (CS). Membrane properties were studied in terms of water flux, water swelling ratio, molecular weight cut off (MWCO), ion-exchange capacity (IEC) and contact angle measurement. Charge on the membrane was confirmed by ionic diffusion potential (DP). It was observed that, DP increased with the increase in the concentration of sPSf. The membrane sPSf:CS 60:40 showed 1000Da MWCO, 14.6mV diffusion potential (DP) and 0.083mM/g of IEC. Similarly sPSf:CS 90:10 showed 10,000Da MWCO, 71.7mV diffusion potential (DP) and 0.176mM/g of IEC. Moreover, membrane sPSf:CS 60:40 showed 93%, 89% and 69% for MgSO 4, Na 2SO 4 and NaCl rejection respectively. © 2012 Elsevier B.V.
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    Preparation and characterization of PPEES/chitosan composite nanofiltration membrane
    (2013) Shenvi, S.S.; Abdul Rashid, S.A.; A.F., A.F.; Kassim, M.A.; Isloor, A.M.
    Composite membrane having chitosan (CH) as the active layer supported on Poly(1,4-phenylene ether ether sulfone) (PPEES) membrane was synthesized in the current study. The chitosan layer was crosslinked by glutaraldehyde in two different concentrations. The scanning electron microscopic images and hydraulic permeability coefficient revealed the ultrafiltration (UF) nature of the neat PPEES membrane. This was used as a new support material for the casting of chitosan layer in order to get composite membranes. The composite nature of the PPEES/CH membranes was confirmed by FESEM and DSC analysis. The Infrared spectroscopy results confirmed the crosslinking of the chitosan surface by glutaraldehyde (GA). The changes in the hydrophobic nature of the PPEES membrane surface due to deposition of chitosan active layer followed by crosslinking were studied by their contact angle measurement and water flux study. From our studies, PPEES has proved to be a good support membrane for preparation of composite membranes. Increase in GA concentration increased the salt rejection of the membrane up to 34% for NaCl and 53% for MgSO4 on one hand with a simultaneous decrease in the flux values. The hydraulic permeability coefficient values confirmed that the prepared membranes are in nanofiltration range. © 2012 Elsevier B.V.
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    Preparation and characterization study of PPEES/chitosan composite membrane crosslinked with tripolyphosphate
    (Elsevier, 2014) Shenvi, S.; A.F., A.F.; Isloor, A.M.
    A novel composite membrane was prepared using chitosan (CH) as the active layer supported on a Poly(1,4-phenylene ether ether sulfone) (PPEES) membrane. The chitosan layer was ionically cross linked with sodium tripolyphosphate (TPP). The composite nature of PPEES/CH membranes was confirmed by Scanning Electron Microscopy (SEM). Infrared (IR) spectroscopy results and SEM-EDX analysis confirmed the crosslinking of chitosan surface with TPP. The membranes exhibited higher crosslinking density in acidic media than in basic media. The changes in the hydrophobic nature of PPEES membrane surface due to deposition of chitosan active layer followed by crosslinking were studied by their contact angle measurement, water flux and water uptake studies. The membranes showed rejection up to 55% and 21% towards MgSO4 and NaCl respectively at pH=5 and a flux recovery ratio of 73%. © 2014 Elsevier B.V.
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    Preparation and characterization of novel PSf/PVP/PANI-nanofiber nanocomposite hollow fiber ultrafiltration membranes and their possible applications for hazardous dye rejection
    (Elsevier, 2015) Kajekar, A.J.; Dodamani, B.M.; Isloor, A.M.; Zulhairun, A.K.; Cheer, N.B.; A.F., A.F.; Shilton, S.J.
    In the present study, PANI (polyaniline)-nanofibers were synthesized by interfacial polymerization technique, dispersed in n-Methyl-2-Pyrrolidone (NMP) solvent and blended with PVP (Polyvinylpyrrolidone)/PSf (Polysulfone) for preparing the novel hollow fiber membrane by dry-wet spinning technique. The newly prepared nanocomposite ultrafiltration hollow fiber membrane is characterized by Scanning Electron Microscope (SEM), Contact Angle, Zeta Potential and Differential Scanning Calorimeter (DSC). Filtration studies are conducted to measure the membrane pure water flux (PWF), rejection of hazardous dye (Reactive Red 120) and fouling resistance. The maximum rejections are obtained for M 0.5 membrane with 99.25% rejection of RR120 hazardous dye at 2. bar pressure. The pure water flux, percentage rejection, antifouling property and thermal resistance increased with an increase in PANI-nanofiber concentration. The contact angle of the membrane decreased with increasing PANI-nanofiber concentration, which indicated increased hydrophilicity of the new membranes. © 2015 Elsevier B.V.
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    Performance enhancement of polysulfone ultrafiltration membrane using TiO2 nanofibers
    (Taylor and Francis Inc. 325 Chestnut St, Suite 800 Philadelphia PA 19106, 2016) Nair, A.K.; Shalin, P.M.; JagadeeshBabu, P.E.
    Titanium dioxide nanofibers were synthesized via alkaline hydrothermal method using TiO2 nanopowder. The hydrothermal method was optimized by studying the operating variables to obtain nanosized TiO2 fibers. These nanofibers were used to make composite polysulfone ultrafiltration membranes along with polyethylene glycol as pore forming agent. The obtained samples were characterized using scanning electron microscope, X-ray diffraction, and attenuated total reflectance infrared spectroscopy. Contact angle measurements were used to estimate hydrophilicity of the membrane. Performance of the membrane was analyzed using pure water flux studies and antifouling studies with bovine serum albumin as the standard protein for rejection. The composite membranes exhibited better performance in both permeability and antifouling property. © 2015 Balaban Desalination Publications. All rights reserved.