Research Publications (Engineering and Built Environment)
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Item Urea-phenol-formaldehyde micro capsules containing linseed oil for self-healing anti corrosive coating applications(VBRI Press, 2016) Patil, Deepak; Rane, Ajay Vasudeo; Kanny, Krishnan; Abitha, V.K.; Sabnis, AnaghaNovel self-repairing Urea-Phenol-Formaldehyde (UPF) microcapsules containing linseed oil were prepared via in-situ polymerization in an oil-in-water emulsion. The main purpose of encapsulation is to control the release of linseed oil, when external conditions such as mechanical stress or energy cause microcapsules to break. These controlled release mechanisms of linseed oil make them suitable for application in self-healing coatings. Chemical structure analyses of microcapsules were studied by Fourier transform infrared spectroscopy (FTIR), optical microscopy and scanning electron microscopy for their structural & morphological illustrations. Controllable particle sizes were determined under optical microscope and as well using particle size analyzer. To determine the healing efficiency, the microcapsules, were incorporated in the epoxy coatings in varying proportions. The effects of the same on anti-corrosion performance was carried out in 5% NaCl aqueous solution (ASTM B117) and Decreasing trend of pencil hardness, scratch hardness, Impact resistance with the increase in concentration of microcapsules was observed. Chemical resistance could also be attributed to the presence of aromatic structures in epoxy which impart chemical stability. Secondary hydroxyl moiety in epoxy chain forms hydrogen bonding with the metal substrate that would contribute to good adhesive forces. Epoxy coatings incorporated with microcapsules showed better corrosion resistance than neat epoxy coating, where neat epoxy coating showed rust and spreading of rust observed on tested panel. Mechanical properties decreased on incorporating microcapsules into epoxy matrix, hence development of mechanical properties without effecting the corrosion properties shall be studied further. Copyright © 2016 VBRI Press.Item Studies on dynamic ageing conditions for Life Cycle Prediction of tyre tread(Journal of Materials and Environment Science, 2016) Abitha, V. K.; Rane, Ajay Vasudeo; Kanny, Krishnan; Thomas, SabuRubber material properties and useful life estimation are very important in design procedure to assure the safety and reliability of tire. The Tire tread compound undergo various stringent condition during its application like strain, temperature etc. In general Arrhenius techniques have been used to predict the life of rubber component using static ageing technique. But such techniques shall not reveal actual use of the application. An attempt has been made to simulate thermal ageing along with dynamic condition in order to match with actual application. Testing equipment has been designed and fabricated to suit this requirement of dynamic ageing of dumbbell specimens which closely matches with the real application. Study also deals with determining the changes in physical properties of tire rubber vulcanizates under different dynamic heat ageing condition and thereby predicting life of component. Mixing was carried out in open mill and compounded rubber was vulcanized by compression molding at 160°C based as per rheometric studies. Physico-mechanical and other properties were determined as per requirement for tread rubber compounds. Morphological studies of the fracture samples were done using SEM to study the changes if any, in the micro structure failure. Accelerated heat aging tests under dynamic condition were carried out to predict the life of tire rubber vulcanizates using Arrhenius technique which predicted the life of rubber vulcanizates of 17.01 days for threshold value and activation energy found to be 197.56kJ/mol.Item Resin infusion analysis of nanoclay filled glass fiber laminates(Elsevier, 2013-11-13) Kanny, Krishnan; Mohan, T. P.This paper focuses on the resin flow characteristics of nanoclay filled glass fiber laminates processed by Vacuum Assisted Resin Infusion Molding (VARIM). Laminates with varying quantities of nanoclays (0–5 wt.%) were prepared and the effect of these nanoclays on the epoxy resin flow characteristics was studied. It was found that the flow rate of resin continuously decreased as nanoclay content continuously increased. The reduction in the flow rate was attributed to the rate of change of curing and the subse-quent change in viscosity of the nanoclay filled resin. Analysis of infusion process by Darcy’s law show that the permeability of the fiber decreased in the nanoclay filled resin system. Nanoclay filled laminates show improved static and dynamic mechanical properties than that of unfilled resin composites.Item Dynamic response of nanocomposite laminates during low, medium and high velocity impact loading(DEStech Publications, 2015-11) Balaganesan, G.; Velmurugan, R.; Kanny, KrishnanThe composite laminates are subjected to impact loading in various conditions with different energy levels. The energy levels are varied by varying mass and speed of the striking mass. The conditions are low velocity of impact with heavy mass, light mass projectile with medium and high velocity of impact. The impact due to bullet is considered as light mass with high velocity of impact. Dynamic response of nanocomposite laminates in drop mass test and projectile impact is studied for low velocity impact. The acceleration and time duration of vibration are found experimentally for the glass/epoxy laminates with and without nano fillers. The values of peak acceleration and period of vibration are compared for the laminates of different thicknesses and percentage of filler dispersion. The damping factor values are predicted for low velocity impact loading by logarithmic decrement method and by FFT spectrum analysis for medium and high velocity impact.Item Infrared heating assisted thermoforming of polypropylene clay nanocomposites(Springer-Verlag, 2014-06-18) Mohan, T. P.; Kanny, KrishnanThe objective of this work is to study the influence of nanoclay addition in PP sheet during infrared (IR) heating assisted thermoforming process. The effect of nanoclay on viscoelastic, friction and dimensional characteristics during sheet forming was examined. The result indicated that the nanoclay addition improves the sagging (sagging depth and sagging disintegration) and plugging (plug depth and friction) properties during sheet forming. The plugging properties of nanoclay filled PP sheet resulted in the improved physical characteristics (minimal change in thickness (Δt) and % di-mensional elongation) when compared with unfilled PP sheet. The nanoclay filled formed PP sheet resulted in improved tensile and dynamic mechanical properties when compared with unfilled formed PP sheet