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Papers by Satyendra Mishra

Research paper thumbnail of Comparative study of the mechanical and flame-retarding properties of polybutadiene rubber filled with nanoparticles and fly ash

Journal of Applied Polymer Science, 2005

A comparative study was performed of fly ash and nano-CaCO3 as fillers in polybutadiene rubber wi... more A comparative study was performed of fly ash and nano-CaCO3 as fillers in polybutadiene rubber with 0, 4, 8 and 12% fly ash and nano-CaCO3. Uniform sheets were prepared of well-compounded rubber. Nano-CaCO3 was synthesized by in situ deposition. The CaCO3 nanoparticles as reinforcing agents improved the tensile strength more than 50% than fly ash, and the toughness and hardness also increased significantly. Up to a 75% reduction in flammability and a 100% improvement in the tear strength were observed with nano-CaCO3.© 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 6–9, 2005

Research paper thumbnail of Preparation, Characterization and Properties of Poly(vinyl chloride)/CaSO4 Nanocomposites

Polymer-plastics Technology and Engineering, 2009

A N-rich Zr–N film with Th3P4 structure (denoted as c-Zr3N4) was grown on Si and glass substrate ... more A N-rich Zr–N film with Th3P4 structure (denoted as c-Zr3N4) was grown on Si and glass substrate by radio frequency (rf) magnetron sputtering technique with high pure Zr as target and high pure N2 as sputtering gas. The crystal structure and composition of the c-Zr3N4 was characterized by X-ray diffractometry, transmission electron microscopy and X-ray photoelectron spectroscopy. The lattice constant

Research paper thumbnail of Studies on characterization of nano CaCO3 prepared by thein situ deposition technique and its application in PP-nano CaCO3 composites

Journal of Polymer Science Part B-polymer Physics, 2005

The elegant approach of in situ deposition technique was used for the synthesis of nano CaCO3. th... more The elegant approach of in situ deposition technique was used for the synthesis of nano CaCO3. the nanosize of particles was confirmed by the X-ray diffraction (XRD) technique. Differential scanning calorimetry (DSC) was used for determination of the enthalpy. The nano CaCO3 polypropylene (PP) composites were prepared by taking 2 and 10 wt % of different nanosizes (21–39 nm) of CaCO3. Conversion of the α phase to β was observed in the case of 2 wt % of a 30-nm sized amount of CaCO3 in a PP composite. The decrement in ΔH and percent crystallinity, as well as the increment in melt temperature were recorded for 6 wt % nano CaCO3 with a decrease in nanosize from 39 to 21 nm. The increment in tensile strength with an increase in the amount of nano CaCO3 was observed, and the lower particle size showed greater improvement. The improvement in thermal and mechanical properties is because of the formation of a greater number of small spherulites uniformly present in the PP matrix. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 107–113, 2004

Research paper thumbnail of Mechanical and flame-retarding properties of styrene–butadiene rubber filled with nano-CaCO3 as a filler and linseed oil as an extender

Journal of Applied Polymer Science, 2005

A nanosize CaCO3 filler was synthesized by an in situ deposition technique, and its size was conf... more A nanosize CaCO3 filler was synthesized by an in situ deposition technique, and its size was confirmed by X-ray diffraction. CaCO3 was prepared in three different sizes (21, 15, and 9 nm). Styrene–butadiene rubber (SBR) was filled with 2–10 wt % nano-CaCO3 with 2% linseed oil as an extender. Nano-CaCO3–SBR rubber composites were compounded on a two-roll mill and molded on a compression-molding machine. Properties such as the specific gravity, swelling index, hardness, tensile strength, abrasion resistance, modulus at 300% elongation, flame retardancy, and elongation at break were measured. Because of the reduction in the nanosize of CaCO3, drastic improvements in the mechanical properties were found. The size of 9 nm showed the highest increase in the tensile strength (3.89 MPa) in comparison with commercial CaCO3 and the two other sizes of nano-CaCO3 up to an 8 wt % loading in SBR. The elongation at break also increased up to 824% for the 9-nm size in comparison with commercial CaCO3 and the two other sizes of nano-CaCO3. Also, these results were compared with nano-CaCO3-filled SBR without linseed oil as an extender. The modulus at 300% elongation, hardness, specific gravity, and flame-retarding properties increased with a reduction in the nanosize with linseed oil as an extender, which helped with the uniform dispersion of nano-CaCO3 in the rubber matrix. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2563–2571, 2005

Research paper thumbnail of Comparative Study on Improvement in Mechanical and Flame Retarding Properties of Epoxy-CaCO3 Nano and Commercial Composites

Polymer-plastics Technology and Engineering, 2005

... PTE-200048299 S. Mishra a , Shirish Sonawane a & Vishal Chitodkar a pages 463-473. ... Th... more ... PTE-200048299 S. Mishra a , Shirish Sonawane a & Vishal Chitodkar a pages 463-473. ... The introduction of Montmorillonite (MNT) clay and its properties were studied by different authors [1] 1. Forenes , TD ; Yoon , PJ ; Keskkula , H. ; Paul , DR Polymer 2001 , 42 , 9929 . ...

Research paper thumbnail of Effect of nano-Mg(OH)2 on the mechanical and flame-retarding properties of polypropylene composites

Journal of Applied Polymer Science, 2004

Nano-Mg(OH)2 was synthesized with an in situ deposition technique, and its size was confirmed by ... more Nano-Mg(OH)2 was synthesized with an in situ deposition technique, and its size was confirmed by X-ray diffraction. A polypropylene–Mg(OH)2 composite was prepared by melt-extrusion processing. The addition of a small quantity of a nanofiller (up to 10 wt %) increased Young's modulus up to 433% with respect to the modulus of virgin polypropylene. The addition of up to 4 wt % Mg(OH)2 produced the maximum increase, and a further decrease in the tensile strength was observed with an increase in the concentration of nano-Mg(OH)2. Increases in the hardness and other properties were due to higher nucleation and the intercalation of polymer chains in the nanolayer galleries. The flame-retarding property was demonstrated by the rate of burning. The time required to burn the nanofilled composite was greater than the time required for virgin polypropylene. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 116–122, 2004

Research paper thumbnail of Effect of nanosize CaSO4 and Ca3(PO4)2 particles on the rheological behavior of polypropylene and its simulation with a mathematical model

Journal of Applied Polymer Science, 2006

Nanosize CaSO4 and Ca3(PO4)2 fillers were synthesized with an in situ deposition technique, and t... more Nanosize CaSO4 and Ca3(PO4)2 fillers were synthesized with an in situ deposition technique, and their sizes were confirmed by X-ray diffraction. CaSO4 was prepared in 12- and 22-nm sizes, and Ca3(PO4)2 was prepared in 13- and 24-nm sizes. Experimental variables, such as torque, shear viscosity, shear stress, and shear rate, of the nanofilled polypropylene (PP) composites were measured with torque rheometry and melt flow index (MFI) measurements. Torque versus time, shear viscosity versus weight percentage, and MFI versus weight percentage were plotted to investigate the rheological behavior of the nanofilled composites. The Cross–Williamson (CW) model was simulated with the MATLAB simulation package to study the thinning behavior of the PP composites. The experimental results show a decrease in the shear viscosity with increasing weight percentage of filler. Shear thinning in the molten PP composites was comparatively greater with decreasing nanosize of CaSO4 and Ca3(PO4)2. This kind of behavior was confirmed by the N parameter as determined from the CW model. The simulation of experimental data also showed similar trends as the theoretical data. At a certain stage, a violation of theoretical data was observed. This was because of practical limitations of the equation, as the equation does not include consideration of the physical situation of chain entanglements. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4190–4196, 2006

Research paper thumbnail of Comparative study of the mechanical and flame-retarding properties of polybutadiene rubber filled with nanoparticles and fly ash

Journal of Applied Polymer Science, 2005

A comparative study was performed of fly ash and nano-CaCO3 as fillers in polybutadiene rubber wi... more A comparative study was performed of fly ash and nano-CaCO3 as fillers in polybutadiene rubber with 0, 4, 8 and 12% fly ash and nano-CaCO3. Uniform sheets were prepared of well-compounded rubber. Nano-CaCO3 was synthesized by in situ deposition. The CaCO3 nanoparticles as reinforcing agents improved the tensile strength more than 50% than fly ash, and the toughness and hardness also increased significantly. Up to a 75% reduction in flammability and a 100% improvement in the tear strength were observed with nano-CaCO3.© 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 6–9, 2005

Research paper thumbnail of Preparation, Characterization and Properties of Poly(vinyl chloride)/CaSO4 Nanocomposites

Polymer-plastics Technology and Engineering, 2009

A N-rich Zr–N film with Th3P4 structure (denoted as c-Zr3N4) was grown on Si and glass substrate ... more A N-rich Zr–N film with Th3P4 structure (denoted as c-Zr3N4) was grown on Si and glass substrate by radio frequency (rf) magnetron sputtering technique with high pure Zr as target and high pure N2 as sputtering gas. The crystal structure and composition of the c-Zr3N4 was characterized by X-ray diffractometry, transmission electron microscopy and X-ray photoelectron spectroscopy. The lattice constant

Research paper thumbnail of Studies on characterization of nano CaCO3 prepared by thein situ deposition technique and its application in PP-nano CaCO3 composites

Journal of Polymer Science Part B-polymer Physics, 2005

The elegant approach of in situ deposition technique was used for the synthesis of nano CaCO3. th... more The elegant approach of in situ deposition technique was used for the synthesis of nano CaCO3. the nanosize of particles was confirmed by the X-ray diffraction (XRD) technique. Differential scanning calorimetry (DSC) was used for determination of the enthalpy. The nano CaCO3 polypropylene (PP) composites were prepared by taking 2 and 10 wt % of different nanosizes (21–39 nm) of CaCO3. Conversion of the α phase to β was observed in the case of 2 wt % of a 30-nm sized amount of CaCO3 in a PP composite. The decrement in ΔH and percent crystallinity, as well as the increment in melt temperature were recorded for 6 wt % nano CaCO3 with a decrease in nanosize from 39 to 21 nm. The increment in tensile strength with an increase in the amount of nano CaCO3 was observed, and the lower particle size showed greater improvement. The improvement in thermal and mechanical properties is because of the formation of a greater number of small spherulites uniformly present in the PP matrix. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 107–113, 2004

Research paper thumbnail of Mechanical and flame-retarding properties of styrene–butadiene rubber filled with nano-CaCO3 as a filler and linseed oil as an extender

Journal of Applied Polymer Science, 2005

A nanosize CaCO3 filler was synthesized by an in situ deposition technique, and its size was conf... more A nanosize CaCO3 filler was synthesized by an in situ deposition technique, and its size was confirmed by X-ray diffraction. CaCO3 was prepared in three different sizes (21, 15, and 9 nm). Styrene–butadiene rubber (SBR) was filled with 2–10 wt % nano-CaCO3 with 2% linseed oil as an extender. Nano-CaCO3–SBR rubber composites were compounded on a two-roll mill and molded on a compression-molding machine. Properties such as the specific gravity, swelling index, hardness, tensile strength, abrasion resistance, modulus at 300% elongation, flame retardancy, and elongation at break were measured. Because of the reduction in the nanosize of CaCO3, drastic improvements in the mechanical properties were found. The size of 9 nm showed the highest increase in the tensile strength (3.89 MPa) in comparison with commercial CaCO3 and the two other sizes of nano-CaCO3 up to an 8 wt % loading in SBR. The elongation at break also increased up to 824% for the 9-nm size in comparison with commercial CaCO3 and the two other sizes of nano-CaCO3. Also, these results were compared with nano-CaCO3-filled SBR without linseed oil as an extender. The modulus at 300% elongation, hardness, specific gravity, and flame-retarding properties increased with a reduction in the nanosize with linseed oil as an extender, which helped with the uniform dispersion of nano-CaCO3 in the rubber matrix. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2563–2571, 2005

Research paper thumbnail of Comparative Study on Improvement in Mechanical and Flame Retarding Properties of Epoxy-CaCO3 Nano and Commercial Composites

Polymer-plastics Technology and Engineering, 2005

... PTE-200048299 S. Mishra a , Shirish Sonawane a & Vishal Chitodkar a pages 463-473. ... Th... more ... PTE-200048299 S. Mishra a , Shirish Sonawane a & Vishal Chitodkar a pages 463-473. ... The introduction of Montmorillonite (MNT) clay and its properties were studied by different authors [1] 1. Forenes , TD ; Yoon , PJ ; Keskkula , H. ; Paul , DR Polymer 2001 , 42 , 9929 . ...

Research paper thumbnail of Effect of nano-Mg(OH)2 on the mechanical and flame-retarding properties of polypropylene composites

Journal of Applied Polymer Science, 2004

Nano-Mg(OH)2 was synthesized with an in situ deposition technique, and its size was confirmed by ... more Nano-Mg(OH)2 was synthesized with an in situ deposition technique, and its size was confirmed by X-ray diffraction. A polypropylene–Mg(OH)2 composite was prepared by melt-extrusion processing. The addition of a small quantity of a nanofiller (up to 10 wt %) increased Young's modulus up to 433% with respect to the modulus of virgin polypropylene. The addition of up to 4 wt % Mg(OH)2 produced the maximum increase, and a further decrease in the tensile strength was observed with an increase in the concentration of nano-Mg(OH)2. Increases in the hardness and other properties were due to higher nucleation and the intercalation of polymer chains in the nanolayer galleries. The flame-retarding property was demonstrated by the rate of burning. The time required to burn the nanofilled composite was greater than the time required for virgin polypropylene. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 116–122, 2004

Research paper thumbnail of Effect of nanosize CaSO4 and Ca3(PO4)2 particles on the rheological behavior of polypropylene and its simulation with a mathematical model

Journal of Applied Polymer Science, 2006

Nanosize CaSO4 and Ca3(PO4)2 fillers were synthesized with an in situ deposition technique, and t... more Nanosize CaSO4 and Ca3(PO4)2 fillers were synthesized with an in situ deposition technique, and their sizes were confirmed by X-ray diffraction. CaSO4 was prepared in 12- and 22-nm sizes, and Ca3(PO4)2 was prepared in 13- and 24-nm sizes. Experimental variables, such as torque, shear viscosity, shear stress, and shear rate, of the nanofilled polypropylene (PP) composites were measured with torque rheometry and melt flow index (MFI) measurements. Torque versus time, shear viscosity versus weight percentage, and MFI versus weight percentage were plotted to investigate the rheological behavior of the nanofilled composites. The Cross–Williamson (CW) model was simulated with the MATLAB simulation package to study the thinning behavior of the PP composites. The experimental results show a decrease in the shear viscosity with increasing weight percentage of filler. Shear thinning in the molten PP composites was comparatively greater with decreasing nanosize of CaSO4 and Ca3(PO4)2. This kind of behavior was confirmed by the N parameter as determined from the CW model. The simulation of experimental data also showed similar trends as the theoretical data. At a certain stage, a violation of theoretical data was observed. This was because of practical limitations of the equation, as the equation does not include consideration of the physical situation of chain entanglements. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4190–4196, 2006