Dr. Rajeev Mehta
Contact No.: 91175 2393440
Dr. Rajeev Mehta is Professor of Chemical Engineering, at Thapar Institute of Engineering & Technology, Patiala, India. Dr. Mehta was appointed in 2000 to Thapar Institute of Engineering & Technology as an Assistant Professor (Reader) in the Department of Chemical Engineering. Here he brought rich research experience in the area of polymers from an earlier stint of about three years at Wright Patterson Air Force Base in Dayton, Ohio, USA as a scientist, and a 1 ½ years stint at SRI, Delhi, India. Also, the research training received at Virginia Tech, USA during his Master’s thesis work also broadened his horrizons.
At Thapar Institute of Engineering & Technology, Dr. Mehta forayed into many new research areas including synthesis, processing of thermosets, and modeling and simulation in Polymers. He is regarded as an authority in the area of polymer nanocomposites after having worked with nanocomposites of Polylactic acid, Polyurethanes, Epoxy fibre reinforced composites, microwave in-situ processing, etc. He also worked in the area of chemical sequestration of carbon dioxide into high value polycarbonates. He has completed seven research projects in 10 years (2007 to 2017). He has 58 peer-reviewed international publications and two encyclopaedia chapters to his credit, and has guided 9 PhD students (two more have submitted their theses) and twenty seven M.Tech students. His current H index is 14, according to google scholar, and the number of citations stands at 821.
His contribution to the study of polymers has been recognized by many awards including a recent award given for the “Best Innovative Young Researcher” at the 4th International Conference on Nanoscience and Nanotechnology (ICONN 2017) at SRM University. The conference was held during 9-11 August 2017 and attracted delegates numbering above 1100 with active participation from Japan, Taiwan, and Australia etc. Earlier in 2015, his research work, in the category of Research in the Field of Polymer Science & Technology for the Innovation in “Chemical Fixation of Carbon dioxide and Propylene Oxide to Poly (Propylene Carbonate) and Cyclic Carbonate” was selected as Joint Runners up (from 47 entries from all over the country) for 5th National Award for Technology Innovation in Petrochemicals & Downstream Plastics Processing Industry, given by Ministry of Fertilizers and Chemicals. Also, recently he was a award winner of the 3rd FICCI Higher Education Excellence in the category of Enabling Research (November 2016) representing Thapar Institute of Engineering & Technology.
Very recently, Dr. Mehta has tried to foray into the interesting world of Enterpreneurship. Towards this, Thapar Institute of Engineering & Technology facilatated a one-month training program on entrepreneurship at University of Groningen, The Netherlands, from 25th Feb to 28th March 2017. Here, Dr. Mehta team won the third prize in the Venture lab weekend at Groningen, The Netherlands, organized by University of Groningen Center for Entrepreneurship.
Project Title: SYNTHESIS OF POLY (LACTIC ACID) USING NEW CATALYSTS AND ITS KINETICS STUDY USING MODELING AND SIMULATION
From May 2007 To December 2010
SummaryPolylactic acid (PLA) has been synthesized with a molecular weight above the one-lac mark at a laboratory scale using three initiators, namely stannous octoate, zinc stearate and dibutyltindimethoxide. Also, a lewis base namely triphenylphosphine has been used as co-initiator with these initiators. Molecular weight has been increased from thousands to several ten thousands g mol-1, when triphenylphosphine was used as co-initiator. The maximum molecular weight of PLA is observed when the Mo/Io ratio is 2568. The effect of dispersion of the initiator plays a very important role in polymerization. A simple and reliable model has been presented for the polymerization of lactide to PLA. The model enables numerical solution of rate equations for initiation, propagation, and termination steps. It is easily extendable to more complex polymerization mechanisms. The simulation can be done in conjunction with the experimental data to yield individual rate constants. It is possible to obtain unique values for various rate constants using Mn versus time and polydispersity data. Accurate rate constants can be predicted using appropriate and reproducible rate data. This methodology offers greater opportunity for capturing high, non-equilibrium polymer yield through appropriately timed termination of the polymerization reaction.
Funding AgencyNaval Research Board (DRDO)
Project Title: BATCH STUDIES FOR SIMULTANEOUS REMOVAL OF COPPER, NICKEL AND ZINC METAL IONS BY BULK LIQUID MEMBRANE TECHNIQUE
From March 2008 To December 2009
SummaryThe experimental values for predicting and analyzing Cu, Ni and Zn extraction from an aqueous solution using commercial Di-2-Ethylhexyl phosphoric acid as extractant has been presented. In the present approach simultaneous reactions of Cu, Ni and Zn complexes with acidic internal reagent, considering reaction irreversibility, is more realistic.
Funding AgencyThapar Institute of Engineering & Technology
Project Title: PREPARATION AND CHARACTERIZATION OF POLYMER/CERAMIC FIBRE AND CELLULOSE COMPOSITE PAPER FOR ELECTRICAL INSULATION
From November 2011 To August 2013
SummaryA composite paper is made by blending electrical grade Kraft with polymeric fibers and binders, to basically get high thermal stability and thus longer working life. The strength of cellulose paper increased by addition of binder but if the quantity of binder is increased beyond a certain limit then tensile strength is decreased. The addition of binder increase the tensile as well as burst strength but increase in fiber decreases the dielectric constant, so more amount of fiber has to be added. The best results are obtained when we use 90% Kraft pulp and 5% PVOH granules, in the absence of fiber, tensile strength of 26 Mpa is achieved which is 33% greater than the base paper. Addition of sufficient amount of synthetic fiber results in an increase in tensile strength without disrupting the sheet structure to a point where tear strength is decreased.
Funding AgencyCrompton Greaves, Mumbai
Project Title: SYNTHESIS OF POLYCARBONATES FROM CARBON DIOXIDE AND PROPYLENE OXIDE
From March 2012 To March 2014
SummaryPreparation of various ligand metal complexes as catalysts and their application in the chemical fixation of propylene oxide and CO2. Various types of co-catalyst were also used in the reactions. Based on the nucleophilic activity, some catalysts were found to be selective for poly(propylene carbonate) [PPC] formation while some were found to be active only for cyclic carbonate formation. Additionally, a comprehensive study on the effects of parameters like monomer to catalyst ratio, catalyst/co-catalyst ratio, stirring rate and reaction conditions like temperature and pressure of CO2 on the molecular weight, yield and selectivity of PPC over propylene carbonate was conducted.
Funding AgencyAICTE (RPS)
Project Title: MICROWAVE ASSISTED POLYMERIZATION OF LACTIC ACID AND POLYLACTIC ACID NANOPARTICLES
From January 2013 To January 2014
SummaryPoly (lactic acid) and PLA/clay nanocomposites were successfully synthesised in a monomode microwave reactor using stannous octoate as an initiator. The yield percentage of PLA increases up to 15-20 mins and subsequently the polymerization product undergoes degradation. The highest molar mass obtained is 6.7 104 for [Mo]/[Io] = 5069. A marked effect of concentration has also been seen on the molar mass determination by GPC. The marked effect of clay percentage loading has been seen on the polymerization yield of PLA/clay nanocomposites. The increase in d-spacing was analyzed by XRD. The exfoliation morphology was obtained which was confirmed by TEM. An excellent compatibility of clay with PLA matrix was confirmed by SEM. The application of microwave irradiation accelerates the polymerization process of PLA and help to form the exfoliated structure of PLA/clay nanocomposites. Microwave assisted in-situ polymerization was proved to be an efficient, cost saving and environmentally friendly benign for the preparation of PLA/clay nanocomposites.
Project Title: PROCESSING AND CHARACTERIZATION OF FIBER REINFORCED POLYMER NANOCOMPOSITES AND THEIR DEGRADATION IN MARINE ENVIRONMENTS
From November 2012 To February 2016
Longterm preservation is a challenging task for anything that resides in an exposed environment and this isespecially true for ships in the marine environment. Hence, the ship hulls need to be manufactured/coated with anti corrosion, sturdy and flexible material with increased life length of the ship. The material suitable for ship hullsrequires high strength to weight ratio, flexibility and high impact strength. Invention of composite materials hasbeen a blessing as it has the ability to handle worse conditions such as extreme temperature, pressure and differentsalt water concentrations while still exhibiting extended service life as compared to conventional materials. Duringour laboratory experiments, we have been able to develop a polymer nanocomposite that can reduce the seawater absorption without the use of any harmful chemicals instead, it makes the water molecules follow a torturouspath, by the presence of carbon nanotubes (CNTs), thus enhancing the durability, strength and longevity of the shiphulls. The approach has now been tested in the laboratory with simulated seawater, and further investigations are currently underway. Additionally, the CNT modified GFRPs have an excellent strength to weight ratio, loweredcenter of gravity, reduced maintenance cost etc. Overall, the present study reports an improved polymer composite material that barricades water diffusion and also proposes a damage monitoring methodology that is non invasive, effective, non contact, in situ and provides real time data of the material degradation during hygrothermal aging.
Also a novel method of silanization, wherein clay minerals have been nano-dispersed in solvent, which increased grafting of silane coupling agents on clay minerals. The incorporation of silane treated clays in epoxy matrix at only 2 phr, led to significant improvement in tensile and flexural properties of glass fiber reinforced nanocomposites because of exfoliation and improved adhesion of clay with epoxy. The hygrothermal resistance is also improved, and thus this would be of immense use to our Navy.
Funding AgencyNaval Research Board (DRDO)
Project Title: STUDIES ON STF – NANOCLAY BASED COMPOSITES FOR PERSONAL ARMOUR SYSTEMS
From May 2014 To November 2017
Shear thickening fluids (STF) are colloidal dispersion of particles in polymer materials with a unique combination of properties and are well known for their ability to absorb large impact in a reversible manner along with reduced weight. For shear thickening properties, the attractive forces (depletion and hydrodynamic forces) should be higher than repulsive forces (electrostatic and polymer stabilization forces) at high shear rates. Modifications of conventional STF with improve elasticity and stability can be used to develop STF to be used for improved or new applications. There are several approaches that can be used to modify the properties of existing STF. Two typical approaches for this can be distinguished. The first approach involve modifying the hydrodynamic forces by adding high aspect ratio clay particles and the second approach involves modifying the particle-solvent interaction and depletion forces by blending solvent with other solvents with a specific chemical functionality such as addition of high viscosity solvents. Such STF combine the material properties of the additives. Current trends towards nanoparticles and viscoelastic polymers make performance of STF increasingly relevant.
Funding AgencyARMREB (DRDO)
SCI - 45
Non-SCI - 10
Conference Papers & Presentation - 50
Contributed Chapters (Encyclopedia) - 02
Patent (Applied) - 01
Dr. Rajeev Mehta is a Chemical Engineer with a BTech degree from IIT Delhi, MS from Virginia Tech, USA and PhD from Thapar Institute of Engineering & Technology. His area of specialization is Polymers. He has been working in the area of polymers for more than twenty five years encompassing the processing, characterization, synthesis and modeling and simulation of polymers. The sub-areas include: Liquid crystalline copolyesters of HBA/PET, Molecular composite blends based on PBZT, Graphitic foams from mesophase pitch, Synthesis of perfluoro ether oil, Pultrusion of polyester + glass fibers composite, Modeling and Simulation of PLA polymerization, Polymer Nanocomposites, Synthesis of PLA using new catalysts, Modeling and Simulation of solar PV and thermal based power plant in India, Polymer-Ceramic composites, Microwave processing of polymers, Biodegradable polymer composites, Effect of radiation on PLGA, Nano-reinforced epoxy FRP, Improved impact strength nano-reinforced FRP, Cellulose paper blended with fibres, Polymer nanocomposites for dye removal, etc. He has 58 peer-reviewed international publications and two encyclopaedia chapters to his credit, and has guided 9 PhD students (two more have submitted their theses) and twenty seven M.Tech students. His current H index is 14, according to google scholar, and the number of citations stands at 821.