Dr Sweta Shukla
@kiet.edu
Assistant Professor
Kiet Group of Institutions
RESEARCH INTERESTS
polymers material science
Scopus Publications
Scopus Publications
Vipin Kumar, Renu Kumari, Dhirendra Kumar Sharma, Sweta Shukla, Akansha Agrwal, and V. K. Sachan
Wiley
Deepika Gaur, Sunita Sharma, Aditya Sharma, Dhirendra Kumar Sharma, and Sweta Shukla
Springer Science and Business Media LLC
This study describes the mechanism of interfacial interaction of the MgO layer with TiO 2 films and demonstrates the modification in optical and photovoltaic properties of MgO/TiO 2 /ITO heterostructures. X-ray diffraction, field emission scanning electron microscopy (FESEM), UV-visible spectroscopy, and x-ray absorption near-edge structure (XANES) at O K-edge, Mg K-edge, and Ti K-edge have been employed to characterize the MgO/TiO 2 /ITO heterostructures. The photovoltaic properties of heterostructures are studied using a solar simulator. FESEM results confirmed the spherical shape of MgO and TiO 2 nanoparticles. Hybridization among the frontier orbitals of O, Mg, and Ti and the presence of Mg 2+ and Ti 4+ ions are confirmed by XANES studies. Assimilation of the MgO layer on TiO 2 film resulted in a significant enhancement in the absorbance characteristics. The MgO film, deposited with maximum spin-coating speed 5000 rpm, exhibited the highest fill factor (FF=0.78), high short-circuit current ( I sc = 12.20 mA/cm 2 ), and open-circuit voltage ( V oc = 0.93 V). The mechanism of high FF in MgO/TiO 2 /ITO structures has been discussed by considering the transparency and electron scavenging from the heterostructures.
Dhirendra Kumar Sharma, Mayora Varshney, Sweta Shukla, Kapil Kumar Sharma, Vipin Kumar, and Anuradha Sharma
Elsevier BV
Sweta Shukla
SAGE Publications
The kinetics of emulsion polymerization of monomers methyl methacrylate (MMA)/ n-butyl methacrylate (BMA) was studied to investigate the effect of cross-linkable monomer poly(propylene glycol diacrylate) (PPGDA). The results showed that by the incorporation of PPGDA rate constant of reaction decreased. Fourier transform infrared spectroscopy and scanning electron microscope were used to characterize the synthesized polymers. The thermal analysis of samples was done by differential scanning calorimetry, and the results were compared by the previous studies with MMA/ n-butyl acrylate (BA) and MMA/2-ethylhexyl acrylate (EHA). The glass transition temperature ( T g) values show that the latexes prepared using BA and EHA as comonomer was suitable for binder purpose, but in the present study the T g is not suitable in case of BMA as higher acrylate comonomer. That may be due to more cross-linking in MMA-BMA-PPGDA. The results conclude that the BA and EHA can be used as the binder, but the use of BMA is limited for the binder in coating applications.
Renu Kumari, Dhirendra K. Sharma, Kapil Sharma, Sweta Shukla, and Vipin Kumar
Elsevier BV
Dhirendra Kumar Sharma, Sweta Shukla, Kapil Kumar Sharma, and Vipin Kumar
Elsevier BV
Sweta Shukla and Dhirendra Kumar Sharma
Elsevier BV
Sweta Shukla
Elsevier BV
Sweta Shukla and JSP Rai
SAGE Publications
Research in the area of coatings focuses primarily on the mechanism for the formation of film on different substrates. Because of environmental hazards related to solvent evaporation and its cost, the ambient cured waterborne systems are emerging as one of the better option for achieving superior properties in high performance applications. The properties like adhesion, gloss, hardness, water resistance, and so on may also get affected by incorporating higher acrylate in the formation of copolymers based on methyl methacrylate (MMA). The swelling behavior of any polymer network depends upon the nature of the polymer, polymer solvent compatibility, and degree of cross-linking. The swelling kinetics of emulsion polymerization of monomers MMA/butyl acrylate was studied to investigate the effect of cross-linkable monomer polypropylene glycol diacrylate (PPGDA). The prepared latex was coated on glass panels and cured at appropriate temperature. According to diffusion-controlled mechanism, the diffusion coefficient for these films varied with degree of cross-linking of the films. From the above discussed swelling behavior of different polymer films, it has been observed that PPGDA content improved the water resistivity of films. This may be due to the cross-linking nature of PPGDA molecule, which increased the cross-link density of the films.
Sweta Shukla and J.S.P. Rai
John Wiley & Sons, Inc.
Sweta Shukla and J. S. P. Rai
SAGE Publications
Aqueous emulsions used as binders in solvent-free paint formulations have to cope with the challenge to guarantee an excellent film formation and appearance as well as good properties. One strategy to fulfill these contradictory requirements is the employment of pure poly(acrylate) resins synthesized by emulsion polymerization. Kinetic studies involving free radical emulsion polymerization of methyl methacrylate (MMA)- co- n-butyl acrylate (BA) are carried out, so that the effect of BA on polymerization of MMA can be interpreted. In this study, the effect of emulsifier and initiator on the kinetics of polymerization was studied. The polymers were characterized using different analytical tools. The surface tension and contact angle of latexes were also measured by varying the concentration of monomer feed ratios. The results indicated that the incorporation of comonomer enhances the properties of coating formulation of polyacrylates.
Sweta Shukla and J. S. P. Rai
Springer Science and Business Media LLC
A recently developed successful approach to achieve the balanced properties involves the copolymerization of film forming monomers like acrylate and methacrylates with crosslinkable monomers. The crosslinker used in the copolymerization of acrylates are basically compound with at least two non-conjugated ethylenic double bonds in their molecule. The kinetics of esterification of multifunctional monomers were investigated using poly(propylene glycol) diacrylates. The effect of methyl group on reaction kinetics was investigated. The diacrylate / dimethacrylate based on polypropylene glycol (molecular weight 400) were synthesized by reacting with acrylic / methacrylic acid in presence of a catalyst. The decrease in acid value and the presence of prominent peak, –C = O stretching, at 1,731 cm−1 showed the formation of diacrylate and dimethacrylate. The value of rate constant for PPGDA at all temperatures were higher than that for PPGDA, indicating that the reactivity of PPG towards acrylic acid is more than methacrylic acid.