Dr.Shailesh Dhoke | Indian Institute of Technology Bombay (original) (raw)
Papers by Dr.Shailesh Dhoke
To improve the glass transition temperature (T g) and heat resistance of polyethylene terephthala... more To improve the glass transition temperature (T g) and heat resistance of polyethylene terephthalate (PET) bottle, poly (ethylene glycol 1,4-cyclohexane dimethylene isosorbide terephthalate) (PEICT) with a unique cyclic structure was introduced into PET. The miscibility of the PET/PEICT blends and their feasibility as a heat resistant bottle were investigated. The introduction of PEICT into PET increases the T g and the PET/PEICT blends exhibit a single T g , indicating good miscibility between PEICT and PET. Furthermore, the T g and crystallinity of the PET/PEICT blends can be adjusted by controlling the amount of PEICT added. The PET/PEICT blends were transparent in the visible light range (no significant change in transparency) because the blends were truly miscible as confirmed by Fox equation. As expected, the introduction of PEICT into PET bottle allows for improved heat resistance and shape stability due to the rigid molecular structure and chirality of the two tetrahydrofuran rings in the isosorbide group of PEICT. Based on our results, the as-prepared PET/PEICT blends with controllable high heat resistance can be used as a cost-effective alternative material for various hot-filling conditions in the beverage industry by adjusting the optimal ratio of PEICT to PET for each product (e.g. fruit juice, tea).
Social Science Research Network, 2022
Chemistry Teacher International
Determination of alkalinity of water sample is generally carried out experimentally by titration ... more Determination of alkalinity of water sample is generally carried out experimentally by titration method using a proper indicator. In the literature, five different cases of possible alkalinities are reported based on the experimental data of acid titration of water sample using phenolphthalein and methyl orange. The reported data is the volume of acid consumption and the relationship between the alkalinity causing ions present in the water sample. However, no systematic approach is available in the literature to understand these experimentally reported volume of acid utilized for neutralization reaction. To make students understand the key features of the reported experimental data, a systematic approach is presented in this study. By using a simple mathematics and a theoretical explanation to the reported reactions taking place during acid titration of water sample, a supplementary document is developed. The theoretical concept in the form of supplementary information is introduced...
A low molecular weight, alkyd-based wateiborne anticorrosive coating was formulated with resin: c... more A low molecular weight, alkyd-based wateiborne anticorrosive coating was formulated with resin: cross-linker ratio of 70:30. The coating was modified with nano-ZnO particles as pigments in different concentrations (0.01%, 0.02% and 0.03% by weight) to form a nano-composite coating. The nano-ZnO modified composite coatings were applied on mild steel substrate by dipping. The coated panels were subjected to various test environments like salt spray, humidity and UV-weathering. The improvements in electrochemical performance of the composite coatings were evaluated using various analytical techniques like scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The result showed that, with increase in the concentration of nano-ZnO there was an improvement in the corrosion resistance and UV resistance of the coatings indicating the positive effect of addition of nano-ZnO particles to the coatings.
Progress in Organic Coatings, 2008
... The performance of any coating is defined if it withstands the external environment effective... more ... The performance of any coating is defined if it withstands the external environment effectively for a long exposure. In order to check the corrosion resistance of the coating, the coating was exposed to accelerated salt-spray, humidity and UV radiations. ...
Progress in Organic Coatings, 2006
Interpenetrating polymer network (IPN) in which two different resins (epoxy and silicone) are not... more Interpenetrating polymer network (IPN) in which two different resins (epoxy and silicone) are not miscible as such with each other is made to do so by using cross-linking agents and catalyst. IPN possess good improved mechanical, chemical, heat and corrosion resistant properties than individual resins. Incorporation of black pigments like graphite, silicon carbide, carbon black and acetylene black has enhanced these properties because of their shape, size, acid and salt solution resistance, conducting nature and heat stability property. Flake structured graphite and hexagonal structured silicon carbide pigments in IPN protect the mild steel structures from corrosive and high temperature atmosphere for longer duration than the other pigments.
Progress in Organic Coatings, 2007
Interpenetrating polymer network (IPN) is a novel type of polymer hybrids, which possess physicoc... more Interpenetrating polymer network (IPN) is a novel type of polymer hybrids, which possess physicochemical properties suitable for high performance coatings. Heat-resistant IPN have been prepared from immiscible resins, epoxy and silicones using a cross-linking agent and a catalyst. The products were analyzed by GPC, FT-IR, TG, DTA and SEM studies. The heat resistance property and corrosion behaviour of the IPNs were also determined. It was different from those of the individual resins. Silicone microdomains could be seen uniformly distributed in epoxy regions. Corrosion resistance property of the IPNs was evaluated by salt spray and impedance measurements. The IPNs withstood longer durations in the salt spray chamber.
Materials Chemistry and Physics, 2009
... Nano-ironoxide with a mean size of 1030 nm and specific area 3540 m 2 g −1 , was procured f... more ... Nano-ironoxide with a mean size of 1030 nm and specific area 3540 m 2 g −1 , was procured from I-CanNano, India. 2.2. Preparation of nano-composite coatings. ... View Within Article. 3. Results and discussion. 3.1. Characterization of nano-Fe 2 O 3 particles. Fig. ...
Journal of Applied Polymer Science, 2009
A nano-composite coating was formed using nano-ZnO as pigment in different concentrations, to a s... more A nano-composite coating was formed using nano-ZnO as pigment in different concentrations, to a specially developed alkyd-based waterborne coating. The nano-ZnO modified composite coatings were applied on mild steel substrate by dipping. The dispersion of nano-ZnO particles in coating system was investigated by scanning electron microscopic and atomic force microscopic techniques. The effect of the addition of these nanopigments on the electrochemical behavior of the coating was investigated in 3.5% NaCl solution, using electrochemical impedance spectroscopy. Coating modified with higher concentration of nano-ZnO particles showed comparatively better performance as was evident from the pore resistance (R po) and coating capacitance (C c) values after 30 days of exposure. In general, the study showed an improvement in the corrosion resistance of the nano-particle modified coatings as compared with the neat coating, confirming the positive effect of nano-particle addition in coatings. V
External coatings used for corrosion protection often have to perform under severely corrosive en... more External coatings used for corrosion protection often have to perform under severely corrosive environments. One major concern regarding coating performance is the negative effect of soluble salts on the steel substrate at the time of coating application, particularly for marine maintenance coating applications. These salts impact the ability of the applied coating systems to protect the steel in several ways including osmotic coating blistering, promotion of under-film metallic corrosion and coating disbondment. This paper focuses on removal of soluble salts contamination by commercially available decontamination processes in relation to external coating systems. We directly compare the effectiveness of four cleaning methods with the performance of ten coating systems. The methodology of surface contamination and preparation of test panels is discussed. After cleaning, sample evaluation for chloride ion contamination levels was carried out using Field method (commercial chloride io...
A nano-composite coating was formed by incorporating nano-ZnO pigments in a waterborne polyuretha... more A nano-composite coating was formed by incorporating nano-ZnO pigments in a waterborne polyurethane dispersion (WPUD) to different loading levels (0.1% and 1.0% by weight). Corrosion performance of the nano-composite coatings were evaluated by applying these nano-composites coatings on mild steel substrate and exposing them to salt-spray, humidity and accelerated UV-weathering. Mechanical properties like scratch resistance, abrasion resistance and pencil hardness were also studied. The electrochemical performance and mechanical properties of the composite coatings were evaluated using various analytical techniques. FTIR technique was used to investigate the interaction between nano-ZnO particles and the polymer functionalities. SEM and AFM were used to investigate dispersion of nano-ZnO particles and the changes in the surface behavior of the modified coatings before and after exposure to the test environment. The optical property of the coating was evaluated using UV-Visible spectr...
Applied Biological Research, 2011
The present study demonstrates the effect of nano-ZnO particles on growth of mung bean (Vigna rad... more The present study demonstrates the effect of nano-ZnO particles on growth of mung bean (Vigna radiata) and chickpea (Cicer arietinum) seedlings. The study was conducted in plant agar media to prevent precipitation of water-insoluble nanoparticles in test units. Various concentrations of nano-ZnO particles in suspension form were introduced to the agar media and its effect on root and shoot growth of seedlings examined. Analytical techniques like optical microscopy and scanning electron microscopy were used to study the architecture of root. Inductive coupled plasma (ICP) was used to determine the uptake of nano-ZnO particles by root. The best response of nano-ZnO on mung bean was observed at 20 ppm and on chickpea at 1 ppm, beyond these concentrations the seedling showed retardation in growth and development thereby suggesting the toxic effect of nano-ZnO particles.
International Journal of Corrosion, 2015
Fusion Bond Epoxy (FBE) coating system was exposed to 5% sodium hydroxide at elevated temperature... more Fusion Bond Epoxy (FBE) coating system was exposed to 5% sodium hydroxide at elevated temperature for 30 days. The result of exposure showed formation of adhere deposit layer, a discolored zone underneath and remaining un-affected bulk of the coating. The deterioration of the coating was characterized using analytical techniques like scanning electron microscopy (SEM), energy-dispersive X-ray (EDAX) spectroscopy, attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), pull-off adhesion, and electrochemical impedance spectroscopy (EIS). Results obtained indicated chemical deterioration of the coating in the discolored zone and leaching of low molecular weight coating component forming deposit layer. Although the adhesion strength and barrier property were not affected, the polymer matrix in the affected zone undergoes severe changes in its surface microstructure, primary chemical structure, and glass transition temperat...
The present study demonstrates the effect of nano-ZnO particles on growth of mung bean (Vigna rad... more The present study demonstrates the effect of nano-ZnO particles on growth of mung bean (Vigna radiata) and chickpea (Cicer arietinum) seedlings. The study was conducted in plant agar media to prevent precipitation of water-insoluble nanoparticles in test units. Various concentrations of nano-ZnO particles in suspension form were introduced to the agar media and its effect on root and shoot growth of seedlings examined. Analytical techniques like optical microscopy and scanning electron microscopy were used to study the architecture of root. Inductive coupled plasma (ICP) was used to determine the uptake of nano-ZnO particles by root. The best response of nano-ZnO on mung bean was observed at 20 ppm and on chickpea at 1 ppm, beyond these concentrations the seedling showed retardation in growth and development thereby suggesting the toxic effect of nano-ZnO particles.
A nano-composite coating was formed by incorporating nano-ZnO pigments in a waterborne polyuretha... more A nano-composite coating was formed by incorporating nano-ZnO pigments in a waterborne polyurethane dispersion (WPUD) to different loading levels (0.1% and 1.0% by weight). Corrosion performance of the nano-composite coatings were evaluated by applying these nano-composites coatings on mild steel substrate and exposing them to salt-spray, humidity and accelerated UV-weathering. Mechanical properties like scratch resistance, abrasion resistance and pencil hardness were also studied. The electrochemical performance and mechanical properties of the composite coatings were evaluated using various analytical techniques. FTIR technique was used to investigate the interaction between nano-ZnO particles and the polymer functionalities. SEM and AFM were used to investigate dispersion of nano-ZnO particles and the changes in the surface behavior of the modified coatings before and after exposure to the test environment. The optical property of the coating was evaluated using UV-Visible spectr...
A nano-composite coating was formed by adding nano-Fe 2 O 3 to a specially developed alkyd based ... more A nano-composite coating was formed by adding nano-Fe 2 O 3 to a specially developed alkyd based waterborne coating system. The interaction of nano-particles with the polymer functionalities was confirmed using FTIR. Curing behavior of the coating was determined by DSC. The uniformity of coating and dispersion of nano-particles in the polymer matrix was investigated using SEM and AFM. The performance of the coating was investigated in terms of their corrosion resistance, UV-resistance, mechanical properties and optical properties. Composite coatings so formed showed enhanced, corrosion resistance, better mechanical properties such as abrasion and scratch hardness and improved UV blocking properties.
ABSTRACT This study investigates the relative benefits of four commercially available decontamina... more ABSTRACT This study investigates the relative benefits of four commercially available decontamination / pre-wash procedures by examining contaminants on prepared steel panels and by comparing the performance of both internal and external tank coatings applied over steel panels prepared using selected substrate preparation procedures. This study investigates the effect of various decontamination processes on the performance of three internal and eight external tank coatings. The obtained results are discussed in this paper
Journal of Nanoparticles, 2013
A nanocomposite coating was formed by incorporating nanoalumina pigment in a waterborne polyureth... more A nanocomposite coating was formed by incorporating nanoalumina pigment in a waterborne polyurethane dispersion (WPUD) to different loading levels (0.1% and 1.0% by weight). Electrochemical performance of the nanocomposite coating was evaluated by applying these nanomodified coatings on mild steel substrate and exposing them to salt-spray, humidity, and accelerated UV weathering. The surface morphology of the composite coating was evaluated using various analytical techniques. SEM and AFM were used to investigate the dispersion of nanoalumina pigment and surface morphological changes of the nanomodified coating, before and after exposure to the test environment. Mechanical properties like scratch resistance were studied by using nanoscratch technique (Nanoindenter TI-900, Hysitron Inc, USA) and hardness using pencil hardness test method. The results showed an improvement in the corrosion, UV weathering, and mechanical properties of the coatings at lower concentration (0.1% by wt), i...
Journal of Nanotechnology, 2011
The present study demonstrates an effect of nano-ZnO particles on the growth of plant seedlings o... more The present study demonstrates an effect of nano-ZnO particles on the growth of plant seedlings of mung (Vigna radiate) and gram (Cicer arietinum). The study was carried out in plant agar media to prevent precipitation of water-insoluble nanoparticles in the test units. Various concentrations of nano-ZnO particles in suspension form were introduced to the agar media, and their effect on the root and shoot growth of the seedlings was examined. The main experimental approach, using correlative light and scanning electron microscopy provided evidence of adsorption of nanoparticles on the root surface. Absorption of nanoparticles by seedlings root was also detected by inductive coupled plasma/atomic emission spectroscopy (ICP-AES). It was found that at certain optimum concentration, the seedlings displayed good growth over control, and beyond that, retardation in growth was observed.
Nanotechnology Development, 2013
The present experimental investigation demonstrates the effect of nano-ZnO, nano-FeO and nano-ZnC... more The present experimental investigation demonstrates the effect of nano-ZnO, nano-FeO and nano-ZnCuFe-oxide particles on the growth of mung (Vigna radiata) seedling. The study was carried out by spraying optimum concentrations of nanoparticles in suspension form on hydroponically grown test units and examining the effect on the shoot growth of seedlings. Based on biomass assay, it was found that the seedlings displayed good growth over control, demonstrating a positive effect of the nanoparticle treatment. The best performance was observed for nano-ZnCuFe-Oxide followed by nano-FeO and nano-ZnO. Absorption of nanoparticles by plant leaves was also detected by inductive coupled plasma/atomic emission spectroscopy.
To improve the glass transition temperature (T g) and heat resistance of polyethylene terephthala... more To improve the glass transition temperature (T g) and heat resistance of polyethylene terephthalate (PET) bottle, poly (ethylene glycol 1,4-cyclohexane dimethylene isosorbide terephthalate) (PEICT) with a unique cyclic structure was introduced into PET. The miscibility of the PET/PEICT blends and their feasibility as a heat resistant bottle were investigated. The introduction of PEICT into PET increases the T g and the PET/PEICT blends exhibit a single T g , indicating good miscibility between PEICT and PET. Furthermore, the T g and crystallinity of the PET/PEICT blends can be adjusted by controlling the amount of PEICT added. The PET/PEICT blends were transparent in the visible light range (no significant change in transparency) because the blends were truly miscible as confirmed by Fox equation. As expected, the introduction of PEICT into PET bottle allows for improved heat resistance and shape stability due to the rigid molecular structure and chirality of the two tetrahydrofuran rings in the isosorbide group of PEICT. Based on our results, the as-prepared PET/PEICT blends with controllable high heat resistance can be used as a cost-effective alternative material for various hot-filling conditions in the beverage industry by adjusting the optimal ratio of PEICT to PET for each product (e.g. fruit juice, tea).
Social Science Research Network, 2022
Chemistry Teacher International
Determination of alkalinity of water sample is generally carried out experimentally by titration ... more Determination of alkalinity of water sample is generally carried out experimentally by titration method using a proper indicator. In the literature, five different cases of possible alkalinities are reported based on the experimental data of acid titration of water sample using phenolphthalein and methyl orange. The reported data is the volume of acid consumption and the relationship between the alkalinity causing ions present in the water sample. However, no systematic approach is available in the literature to understand these experimentally reported volume of acid utilized for neutralization reaction. To make students understand the key features of the reported experimental data, a systematic approach is presented in this study. By using a simple mathematics and a theoretical explanation to the reported reactions taking place during acid titration of water sample, a supplementary document is developed. The theoretical concept in the form of supplementary information is introduced...
A low molecular weight, alkyd-based wateiborne anticorrosive coating was formulated with resin: c... more A low molecular weight, alkyd-based wateiborne anticorrosive coating was formulated with resin: cross-linker ratio of 70:30. The coating was modified with nano-ZnO particles as pigments in different concentrations (0.01%, 0.02% and 0.03% by weight) to form a nano-composite coating. The nano-ZnO modified composite coatings were applied on mild steel substrate by dipping. The coated panels were subjected to various test environments like salt spray, humidity and UV-weathering. The improvements in electrochemical performance of the composite coatings were evaluated using various analytical techniques like scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The result showed that, with increase in the concentration of nano-ZnO there was an improvement in the corrosion resistance and UV resistance of the coatings indicating the positive effect of addition of nano-ZnO particles to the coatings.
Progress in Organic Coatings, 2008
... The performance of any coating is defined if it withstands the external environment effective... more ... The performance of any coating is defined if it withstands the external environment effectively for a long exposure. In order to check the corrosion resistance of the coating, the coating was exposed to accelerated salt-spray, humidity and UV radiations. ...
Progress in Organic Coatings, 2006
Interpenetrating polymer network (IPN) in which two different resins (epoxy and silicone) are not... more Interpenetrating polymer network (IPN) in which two different resins (epoxy and silicone) are not miscible as such with each other is made to do so by using cross-linking agents and catalyst. IPN possess good improved mechanical, chemical, heat and corrosion resistant properties than individual resins. Incorporation of black pigments like graphite, silicon carbide, carbon black and acetylene black has enhanced these properties because of their shape, size, acid and salt solution resistance, conducting nature and heat stability property. Flake structured graphite and hexagonal structured silicon carbide pigments in IPN protect the mild steel structures from corrosive and high temperature atmosphere for longer duration than the other pigments.
Progress in Organic Coatings, 2007
Interpenetrating polymer network (IPN) is a novel type of polymer hybrids, which possess physicoc... more Interpenetrating polymer network (IPN) is a novel type of polymer hybrids, which possess physicochemical properties suitable for high performance coatings. Heat-resistant IPN have been prepared from immiscible resins, epoxy and silicones using a cross-linking agent and a catalyst. The products were analyzed by GPC, FT-IR, TG, DTA and SEM studies. The heat resistance property and corrosion behaviour of the IPNs were also determined. It was different from those of the individual resins. Silicone microdomains could be seen uniformly distributed in epoxy regions. Corrosion resistance property of the IPNs was evaluated by salt spray and impedance measurements. The IPNs withstood longer durations in the salt spray chamber.
Materials Chemistry and Physics, 2009
... Nano-ironoxide with a mean size of 1030 nm and specific area 3540 m 2 g −1 , was procured f... more ... Nano-ironoxide with a mean size of 1030 nm and specific area 3540 m 2 g −1 , was procured from I-CanNano, India. 2.2. Preparation of nano-composite coatings. ... View Within Article. 3. Results and discussion. 3.1. Characterization of nano-Fe 2 O 3 particles. Fig. ...
Journal of Applied Polymer Science, 2009
A nano-composite coating was formed using nano-ZnO as pigment in different concentrations, to a s... more A nano-composite coating was formed using nano-ZnO as pigment in different concentrations, to a specially developed alkyd-based waterborne coating. The nano-ZnO modified composite coatings were applied on mild steel substrate by dipping. The dispersion of nano-ZnO particles in coating system was investigated by scanning electron microscopic and atomic force microscopic techniques. The effect of the addition of these nanopigments on the electrochemical behavior of the coating was investigated in 3.5% NaCl solution, using electrochemical impedance spectroscopy. Coating modified with higher concentration of nano-ZnO particles showed comparatively better performance as was evident from the pore resistance (R po) and coating capacitance (C c) values after 30 days of exposure. In general, the study showed an improvement in the corrosion resistance of the nano-particle modified coatings as compared with the neat coating, confirming the positive effect of nano-particle addition in coatings. V
External coatings used for corrosion protection often have to perform under severely corrosive en... more External coatings used for corrosion protection often have to perform under severely corrosive environments. One major concern regarding coating performance is the negative effect of soluble salts on the steel substrate at the time of coating application, particularly for marine maintenance coating applications. These salts impact the ability of the applied coating systems to protect the steel in several ways including osmotic coating blistering, promotion of under-film metallic corrosion and coating disbondment. This paper focuses on removal of soluble salts contamination by commercially available decontamination processes in relation to external coating systems. We directly compare the effectiveness of four cleaning methods with the performance of ten coating systems. The methodology of surface contamination and preparation of test panels is discussed. After cleaning, sample evaluation for chloride ion contamination levels was carried out using Field method (commercial chloride io...
A nano-composite coating was formed by incorporating nano-ZnO pigments in a waterborne polyuretha... more A nano-composite coating was formed by incorporating nano-ZnO pigments in a waterborne polyurethane dispersion (WPUD) to different loading levels (0.1% and 1.0% by weight). Corrosion performance of the nano-composite coatings were evaluated by applying these nano-composites coatings on mild steel substrate and exposing them to salt-spray, humidity and accelerated UV-weathering. Mechanical properties like scratch resistance, abrasion resistance and pencil hardness were also studied. The electrochemical performance and mechanical properties of the composite coatings were evaluated using various analytical techniques. FTIR technique was used to investigate the interaction between nano-ZnO particles and the polymer functionalities. SEM and AFM were used to investigate dispersion of nano-ZnO particles and the changes in the surface behavior of the modified coatings before and after exposure to the test environment. The optical property of the coating was evaluated using UV-Visible spectr...
Applied Biological Research, 2011
The present study demonstrates the effect of nano-ZnO particles on growth of mung bean (Vigna rad... more The present study demonstrates the effect of nano-ZnO particles on growth of mung bean (Vigna radiata) and chickpea (Cicer arietinum) seedlings. The study was conducted in plant agar media to prevent precipitation of water-insoluble nanoparticles in test units. Various concentrations of nano-ZnO particles in suspension form were introduced to the agar media and its effect on root and shoot growth of seedlings examined. Analytical techniques like optical microscopy and scanning electron microscopy were used to study the architecture of root. Inductive coupled plasma (ICP) was used to determine the uptake of nano-ZnO particles by root. The best response of nano-ZnO on mung bean was observed at 20 ppm and on chickpea at 1 ppm, beyond these concentrations the seedling showed retardation in growth and development thereby suggesting the toxic effect of nano-ZnO particles.
International Journal of Corrosion, 2015
Fusion Bond Epoxy (FBE) coating system was exposed to 5% sodium hydroxide at elevated temperature... more Fusion Bond Epoxy (FBE) coating system was exposed to 5% sodium hydroxide at elevated temperature for 30 days. The result of exposure showed formation of adhere deposit layer, a discolored zone underneath and remaining un-affected bulk of the coating. The deterioration of the coating was characterized using analytical techniques like scanning electron microscopy (SEM), energy-dispersive X-ray (EDAX) spectroscopy, attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), pull-off adhesion, and electrochemical impedance spectroscopy (EIS). Results obtained indicated chemical deterioration of the coating in the discolored zone and leaching of low molecular weight coating component forming deposit layer. Although the adhesion strength and barrier property were not affected, the polymer matrix in the affected zone undergoes severe changes in its surface microstructure, primary chemical structure, and glass transition temperat...
The present study demonstrates the effect of nano-ZnO particles on growth of mung bean (Vigna rad... more The present study demonstrates the effect of nano-ZnO particles on growth of mung bean (Vigna radiata) and chickpea (Cicer arietinum) seedlings. The study was conducted in plant agar media to prevent precipitation of water-insoluble nanoparticles in test units. Various concentrations of nano-ZnO particles in suspension form were introduced to the agar media and its effect on root and shoot growth of seedlings examined. Analytical techniques like optical microscopy and scanning electron microscopy were used to study the architecture of root. Inductive coupled plasma (ICP) was used to determine the uptake of nano-ZnO particles by root. The best response of nano-ZnO on mung bean was observed at 20 ppm and on chickpea at 1 ppm, beyond these concentrations the seedling showed retardation in growth and development thereby suggesting the toxic effect of nano-ZnO particles.
A nano-composite coating was formed by incorporating nano-ZnO pigments in a waterborne polyuretha... more A nano-composite coating was formed by incorporating nano-ZnO pigments in a waterborne polyurethane dispersion (WPUD) to different loading levels (0.1% and 1.0% by weight). Corrosion performance of the nano-composite coatings were evaluated by applying these nano-composites coatings on mild steel substrate and exposing them to salt-spray, humidity and accelerated UV-weathering. Mechanical properties like scratch resistance, abrasion resistance and pencil hardness were also studied. The electrochemical performance and mechanical properties of the composite coatings were evaluated using various analytical techniques. FTIR technique was used to investigate the interaction between nano-ZnO particles and the polymer functionalities. SEM and AFM were used to investigate dispersion of nano-ZnO particles and the changes in the surface behavior of the modified coatings before and after exposure to the test environment. The optical property of the coating was evaluated using UV-Visible spectr...
A nano-composite coating was formed by adding nano-Fe 2 O 3 to a specially developed alkyd based ... more A nano-composite coating was formed by adding nano-Fe 2 O 3 to a specially developed alkyd based waterborne coating system. The interaction of nano-particles with the polymer functionalities was confirmed using FTIR. Curing behavior of the coating was determined by DSC. The uniformity of coating and dispersion of nano-particles in the polymer matrix was investigated using SEM and AFM. The performance of the coating was investigated in terms of their corrosion resistance, UV-resistance, mechanical properties and optical properties. Composite coatings so formed showed enhanced, corrosion resistance, better mechanical properties such as abrasion and scratch hardness and improved UV blocking properties.
ABSTRACT This study investigates the relative benefits of four commercially available decontamina... more ABSTRACT This study investigates the relative benefits of four commercially available decontamination / pre-wash procedures by examining contaminants on prepared steel panels and by comparing the performance of both internal and external tank coatings applied over steel panels prepared using selected substrate preparation procedures. This study investigates the effect of various decontamination processes on the performance of three internal and eight external tank coatings. The obtained results are discussed in this paper
Journal of Nanoparticles, 2013
A nanocomposite coating was formed by incorporating nanoalumina pigment in a waterborne polyureth... more A nanocomposite coating was formed by incorporating nanoalumina pigment in a waterborne polyurethane dispersion (WPUD) to different loading levels (0.1% and 1.0% by weight). Electrochemical performance of the nanocomposite coating was evaluated by applying these nanomodified coatings on mild steel substrate and exposing them to salt-spray, humidity, and accelerated UV weathering. The surface morphology of the composite coating was evaluated using various analytical techniques. SEM and AFM were used to investigate the dispersion of nanoalumina pigment and surface morphological changes of the nanomodified coating, before and after exposure to the test environment. Mechanical properties like scratch resistance were studied by using nanoscratch technique (Nanoindenter TI-900, Hysitron Inc, USA) and hardness using pencil hardness test method. The results showed an improvement in the corrosion, UV weathering, and mechanical properties of the coatings at lower concentration (0.1% by wt), i...
Journal of Nanotechnology, 2011
The present study demonstrates an effect of nano-ZnO particles on the growth of plant seedlings o... more The present study demonstrates an effect of nano-ZnO particles on the growth of plant seedlings of mung (Vigna radiate) and gram (Cicer arietinum). The study was carried out in plant agar media to prevent precipitation of water-insoluble nanoparticles in the test units. Various concentrations of nano-ZnO particles in suspension form were introduced to the agar media, and their effect on the root and shoot growth of the seedlings was examined. The main experimental approach, using correlative light and scanning electron microscopy provided evidence of adsorption of nanoparticles on the root surface. Absorption of nanoparticles by seedlings root was also detected by inductive coupled plasma/atomic emission spectroscopy (ICP-AES). It was found that at certain optimum concentration, the seedlings displayed good growth over control, and beyond that, retardation in growth was observed.
Nanotechnology Development, 2013
The present experimental investigation demonstrates the effect of nano-ZnO, nano-FeO and nano-ZnC... more The present experimental investigation demonstrates the effect of nano-ZnO, nano-FeO and nano-ZnCuFe-oxide particles on the growth of mung (Vigna radiata) seedling. The study was carried out by spraying optimum concentrations of nanoparticles in suspension form on hydroponically grown test units and examining the effect on the shoot growth of seedlings. Based on biomass assay, it was found that the seedlings displayed good growth over control, demonstrating a positive effect of the nanoparticle treatment. The best performance was observed for nano-ZnCuFe-Oxide followed by nano-FeO and nano-ZnO. Absorption of nanoparticles by plant leaves was also detected by inductive coupled plasma/atomic emission spectroscopy.