Viraj Bhingardive - Academia.edu (original) (raw)
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Papers by Viraj Bhingardive
RSC Adv., 2015
Various Ni x Co 1Àx alloys (with x varying from 0-60 wt%, Ni: nickel, Co: cobalt) were prepared b... more Various Ni x Co 1Àx alloys (with x varying from 0-60 wt%, Ni: nickel, Co: cobalt) were prepared by vacuum arc melting and mixed with polyvinylidene fluoride (PVDF) to design lightweight, flexible and corrosion resistant materials that can attenuate electromagnetic radiation. The saturation magnetization scaled with the fraction of Co in the alloy. Two key properties such as high-magnetic permeability and high-electrical conductivity were targeted. While the former was achieved using a Ni-Co alloy, multiwalled carbon nanotubes (CNTs) in the composites accomplished the latter. A unique approach was adopted to prepare the composites wherein PVDF powder along with CNTs and Ni-Co flakes were made into a paste, using a solvent, followed by hot pressing. Interestingly, CNTs facilitated in uniform dispersion of the Ni-Co alloy in PVDF, as manifested from synergistic improvement in the electrical conductivity. A significant improvement in the shielding effectiveness (41 dB, >99.99% attenuation) was achieved with the addition of 50 wt% of Ni 40 Co 60 alloy and 3 wt% CNTs. Intriguingly, due to the unique processing technique adopted here, the flexibility of the composites was retained and more interestingly, the composites were resistant to corrosion as compared to only Ni-Co alloy. Fig. 2 (a) Preparation of PVDF/CNT/Ni-Co composite (b) XRD pattern for PVDF/CNTs-Ni-Co composite (c) hysteresis loop for PVDF/Ni 40 Co 60 and PVDF/CNT/Ni 40 Co 60 composite. 35912 | RSC Adv., 2015, 5, 35909-35916 This journal is
Construction of ultrathin multilayer polymer nanocomposite films by precise layer-by-layer (LbL) ... more Construction of ultrathin multilayer polymer nanocomposite films by precise layer-by-layer (LbL) architectural assembly with tailor-made properties has been achieved here to block incoming EM radiation. To accomplish this, Mn (manganese)–ferrite nanoparticles were synthesized and incorporated in a thermoplastic matrix (PVDF, poly-vinylidene fluoride) along with conductive MWNTs (PNTMn–Fe) by a facile solution blending process. These nanocomposite films were used as outer layers of the LbL assembly. In order to scavenge the transmitted radiation through PNTMn–Fe layers, PVDF films sandwiched with a Ni (nickel)-deposited woven carbon fiber (CF) mat (PCF@NiP), designed using a facile electroless deposition technique. These layers were used as inner layers of the LbL assembly. The different layers were then stacked and hot pressed into a composite structure. This ultrathin (0.60 mm) multilayer architecture showed an extraordinary (52 dB at 18 GHz) shielding effectiveness and thereby promises a smart approach to accomplish a lightweight, high performance , EMI shielding material.
RSC Adv., 2015
Various Ni x Co 1Àx alloys (with x varying from 0-60 wt%, Ni: nickel, Co: cobalt) were prepared b... more Various Ni x Co 1Àx alloys (with x varying from 0-60 wt%, Ni: nickel, Co: cobalt) were prepared by vacuum arc melting and mixed with polyvinylidene fluoride (PVDF) to design lightweight, flexible and corrosion resistant materials that can attenuate electromagnetic radiation. The saturation magnetization scaled with the fraction of Co in the alloy. Two key properties such as high-magnetic permeability and high-electrical conductivity were targeted. While the former was achieved using a Ni-Co alloy, multiwalled carbon nanotubes (CNTs) in the composites accomplished the latter. A unique approach was adopted to prepare the composites wherein PVDF powder along with CNTs and Ni-Co flakes were made into a paste, using a solvent, followed by hot pressing. Interestingly, CNTs facilitated in uniform dispersion of the Ni-Co alloy in PVDF, as manifested from synergistic improvement in the electrical conductivity. A significant improvement in the shielding effectiveness (41 dB, >99.99% attenuation) was achieved with the addition of 50 wt% of Ni 40 Co 60 alloy and 3 wt% CNTs. Intriguingly, due to the unique processing technique adopted here, the flexibility of the composites was retained and more interestingly, the composites were resistant to corrosion as compared to only Ni-Co alloy. Fig. 2 (a) Preparation of PVDF/CNT/Ni-Co composite (b) XRD pattern for PVDF/CNTs-Ni-Co composite (c) hysteresis loop for PVDF/Ni 40 Co 60 and PVDF/CNT/Ni 40 Co 60 composite. 35912 | RSC Adv., 2015, 5, 35909-35916 This journal is
Construction of ultrathin multilayer polymer nanocomposite films by precise layer-by-layer (LbL) ... more Construction of ultrathin multilayer polymer nanocomposite films by precise layer-by-layer (LbL) architectural assembly with tailor-made properties has been achieved here to block incoming EM radiation. To accomplish this, Mn (manganese)–ferrite nanoparticles were synthesized and incorporated in a thermoplastic matrix (PVDF, poly-vinylidene fluoride) along with conductive MWNTs (PNTMn–Fe) by a facile solution blending process. These nanocomposite films were used as outer layers of the LbL assembly. In order to scavenge the transmitted radiation through PNTMn–Fe layers, PVDF films sandwiched with a Ni (nickel)-deposited woven carbon fiber (CF) mat (PCF@NiP), designed using a facile electroless deposition technique. These layers were used as inner layers of the LbL assembly. The different layers were then stacked and hot pressed into a composite structure. This ultrathin (0.60 mm) multilayer architecture showed an extraordinary (52 dB at 18 GHz) shielding effectiveness and thereby promises a smart approach to accomplish a lightweight, high performance , EMI shielding material.