Manoranjan Patri - Academia.edu (original) (raw)
Papers by Manoranjan Patri
CRC Press eBooks, Mar 23, 2022
Journal of Coatings Technology and Research, 2021
It is well established that crosslinked polydimethylsiloxane (PDMS) based coatings have efficacio... more It is well established that crosslinked polydimethylsiloxane (PDMS) based coatings have efficacious foul release characteristics. However, a trade-off between mechanical integrity of filled and crosslinked PDMS based coatings and their foul release performance has been a bottleneck for producing efficient and durable coatings. In the present study, we report a dual approach of nano-reinforcement of a bimodal PDMS network as a strategy to produce simultaneously reinforced and toughened PDMS networks with facile release of macrofoulants from their surfaces. The nanocomposites of both unimodal and bimodal PDMS networks were prepared using oligomeric dihydroxyl functional PDMS precursor chains differing in their molecular weights by a factor of five and commercial Cloisite-20A nanoclay as the nanofiller. The clay layers were found to be mildly intercalated in the PDMS matrix, as revealed from investigations by scattering and imaging techniques at different length scales. While the unimodal PDMS networks did show nanoclay induced simultaneous reinforcement and toughening, at equivalent clay loadings, the bimodal PDMS nanocomposites seemed to stretch further with characteristic strain hardening before fracture. Dynamic mechanical analysis (DMA) and swelling studies of the nancomposites further confirmed the nanoclay induced reinforcement effect of the bimodal PDMS host matrix. The intrinsic low surface energy characteristics of PDMS were retained by bimodal blending of long and short chains and its subsequent nano-reinforcement. Macrofouling studies by panel immersion and release force measurements revealed that the macrofoulants could be dislodged from the nanocomposite coatings with a shear force < 0.05 MPa.
Journal of Physics: Conference Series, 2015
The effect of nanoclay dispersion on the thermo-mechanical properties of an unsaturated polyester... more The effect of nanoclay dispersion on the thermo-mechanical properties of an unsaturated polyester thermoset resin was studied by flexural and dynamic mechanical property measurements. Transmission electron microscopy studies revealed intercalated clay dispersion morphology in the nanocomposites. The thermomechanical measurements showed a steady decrease in the flexural strength and a relaxation temperature, with only moderate increase in the storage modulus at 1% clay loading, followed by a drop at higher clay loadings. In order to understand the absence of nano-effect in this case, free volume measurements were carried out by using positron annihilation lifetime spectroscopy. A bimodal distribution of o-Ps life times was observed. Nanoclay loading resulted in the increase of the o-Ps intensity corresponding to the longest life time as well as free volume fraction suggesting diminished chain packing efficiency in the nanocomposites. We posit that nanoclay induced decreased chain packing efficiency and the presence of higher free volume size elements might cause deterioration in mechanical properties of the nanocomposites.
Progress in Organic Coatings, 2016
Abstract A series of segmented polydimethylsiloxane based poly(urethane-urea) copolymers (PDMSPU)... more Abstract A series of segmented polydimethylsiloxane based poly(urethane-urea) copolymers (PDMSPU) of varied hard segment contents were prepared by moisture curing prepolymers of isophorone diisocyanate capped polydimethylsiloxane. Quantitative analysis of hydrogen bonding characteristics of the segmented copolymers was conducted by using Fourier transform infrared spectroscopy (FTIR). The carbonyl stretching bands were deconvoluted into components corresponding to different free and hydrogen bonded groups. The studies revealed the presence of unusually ordered urea domains in the segmented copolymers evidenced from peaks at 1622–1632 cm −1 , despite hitherto reported constraints to such ordered domain formation in these copolymers. This in turn manifested in the appearance of crystalline peaks in the wide angle X-ray diffraction (WAXD) profiles of the copolymers, which could also be directly visualized by scanning electron microscopy (SEM) and polarized optical microscopy (POM) studies. The effect of these morphological features on the thermomechanical properties of the segmented copolymers was investigated by dynamic mechanical analysis, tensile testing and hardness measurements. A good correlation between the hydrogen bonding characteristics and thermomechanical properties of the copolymers could be established.
ABSTRACT A basis for quantitative analysis of the reinforcement mechanism of polyurethane-urea/cl... more ABSTRACT A basis for quantitative analysis of the reinforcement mechanism of polyurethane-urea/clay nanocomposites using two characterization methods, positron annihilation life time spectroscopy (PALS) and dynamic mechanical analysis (DMA) is provided. DMA was used to measure the constrained volume fraction of amorphous soft segments induced by nanoclay and the storage modulus of the nanocomposites. The interfacial interactions in the nanocomposites were investigated by PALS. The modulus enhancement of the organoclay nanocomposites was found to have a good correlation with the volume fraction of the constrained region and the interfacial interactions.
AIP Conference Proceedings, 2010
... Pushkar N. Patil, SK Rath, K. Sudarshan, D. Dutta, M. Patri, PK Pujari. Abstract. ... The wat... more ... Pushkar N. Patil, SK Rath, K. Sudarshan, D. Dutta, M. Patri, PK Pujari. Abstract. ... The water uptake by the polymer is influenced by free volumes, the chemical nature and the segmental relaxation in between the molecular chains. Keywords. Solids (rheology). ...
Structural features of polyurethane-urea (PUU)/organoclay nanocomposites have been investigated b... more Structural features of polyurethane-urea (PUU)/organoclay nanocomposites have been investigated by FTIR and small angle x-ray scattering techniques. It is found that the clay has significant influence on morphology of the hard segments (HS) of the PUU. The HS domains which have rough surface, becomes more compact with mass fractal morphology with increase of clay content. FTIR suggests the clay interacts
Radiation Physics and Chemistry, 2010
Acrylic acid (AA) was grafted onto PET films by preirradiation method using a 60 Co g-radiation s... more Acrylic acid (AA) was grafted onto PET films by preirradiation method using a 60 Co g-radiation source. Microstructural investigation of the PET-g-AA copolymers has been carried out by wide angle X-ray diffraction (WAXD), dynamic mechanical analysis (DMA) and positron annihilation lifetime spectroscopy (PALS) techniques. The WAXD results showed only marginal variation in the crystallinity of the graft copolymers. Dynamic mechanical analysis showed an increase in the temperature of the arelaxation and the tan d value of subroom temperature secondary relaxations. From the PALS results, a complex variation of the free volume parameters, i.e. the o-positronium lifetime (t 3), its intensity (I 3), fractional free volume (f v) and the intermediate lifetime component was observed for the graft copolymers. Multiple phenomena of the effect of secondary relaxations, additive behavior of the individual polymer free volume parameters and effects from interfacial defects have been invoked to understand the fluctuational nature of the free volume properties in the graft copolymers.
Progress in Organic Coatings, 2010
Application of polymeric coatings is one of the methods for protection of mild steel against corr... more Application of polymeric coatings is one of the methods for protection of mild steel against corrosion. In the present work, blends of different grades of ethylene vinyl acetate (EVA) with varying vinyl acetate (VAc) content viz. 18%, 28%, 40% and hydrolyzed EVA ie, ethylene ...
Progress in Organic Coatings, 2009
Dispersion of nanoclay (NC) in polymer blend system is governed by the sequence of addition of di... more Dispersion of nanoclay (NC) in polymer blend system is governed by the sequence of addition of different ingredients. In the present work nanoclay was added in different sequences to blend composition such as ethylene vinyl acetate (EVA)/low density ...
Progress in Organic Coatings, 2008
Ethylene vinyl acetate (EVA) copolymer with varying vinyl acetate (VAc) content, viz. 18%, 28% an... more Ethylene vinyl acetate (EVA) copolymer with varying vinyl acetate (VAc) content, viz. 18%, 28% and 40% has been hydrolyzed using alcoholic NaOH solution. Fourier Transform Infrared Spectroscopy (FTIR) analyses of hydrolyzed polymer showed the presence of ...
Progress in Organic Coatings, 2008
Effect of catalysts on curing behaviour, phase morphology and surface properties of a moisture cu... more Effect of catalysts on curing behaviour, phase morphology and surface properties of a moisture cured polyurethane-urea (MCPU) coating has been studied. The prepolymer, prepared by capping hydroxy terminated polybutadiene (HTPB) with isophorone diisocyanate (IPDI), was cured with moisture using different urethane catalysts at 30°C and relative humidity of 60%. Fourier transform infrared spectroscopy (FTIR) was used to monitor the curing
Progress in Organic Coatings, 2009
... SK Rath a , JG Chavan a , S. Sasane a , Alips Srivastava a , M. Patri a , AB Samui a , Corres... more ... SK Rath a , JG Chavan a , S. Sasane a , Alips Srivastava a , M. Patri a , AB Samui a , Corresponding Author Contact Information , E-mail The Corresponding ... Diglycidyl ether of neopentyl glycol, XR-87 (epoxy equivalent weight 180 ± 5 g/equiv.), was purchased from Atul ...
Polymers for Advanced Technologies, 2004
A Novel solid polymer electrolyte (SPE) membrane containing both COOH and SO3H group has been p... more A Novel solid polymer electrolyte (SPE) membrane containing both COOH and SO3H group has been prepared by simultaneous method of radiation grafting of acrylic acid onto FEP followed by sulfonation. The presence of weakly acidic acrylic acid controls the swelling in water ...
Journal of Polymer Engineering, 1991
2 Introduction 3 Procedure 4 Conditions 4 Appearance 4 Characterization 4 Glass Transition Temper... more 2 Introduction 3 Procedure 4 Conditions 4 Appearance 4 Characterization 4 Glass Transition Temperature (Tg) 6 Polymer Melting Temperature (PMT) 8 Thermogravimetric Studies 9 Flammability Characteristics 11 Electrical Properties 12 Application 13 PVC Plasticization 14 Coating 15 Conclusion 16 References 17 VoL 10, Nos. 1-3,1991 Halogenation of Atactic Polypropylene
Journal of Membrane Science, 2011
Cross-linked sulfonated poly (ether ether ketone) (SPEEK)/reactive organoclay (Cloisite-30B) nano... more Cross-linked sulfonated poly (ether ether ketone) (SPEEK)/reactive organoclay (Cloisite-30B) nanocomposite membranes were fabricated using 1,4-bis (hydroxymethyl) benzene (BHMB) as cross-linker and Cloisite-30B organoclay as the pseudo cross-linker. The cross-linked SPEEK/clay nanocomposite membranes were prepared via solution intercalation method. Participation of reactive organoclay in the cross-linking process was established from ion exchange capacity (IEC) measurements and FTIR studies. Wide angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM) confirmed mixed clay dispersion morphology of intercalation and partial exfoliation of the clay platelets in the crosslinked SPEEK/clay nanocomposite membrane. The cross-linked SPEEK/clay nanocomposite membranes were characterized for their thermal and physical properties as a function of clay loading. The characteristics of the cross-linked nanocomposite membranes were then compared with pristine SPEEK membrane. The membrane stability, i.e. liquid uptake in water and in aqueous methanol solution, oxidative stability as well as mechanical and thermal stability were found to significantly improve with incorporation of reactive organoclay into the cross-linked SPEEK polymer matrix, without affecting the protonic conductivity appreciably.
Journal of Applied Polymer Science, 2008
Ionic polymer-metal composites have been made from radiation grafted fluorinated ethylene propyle... more Ionic polymer-metal composites have been made from radiation grafted fluorinated ethylene propylene (FEP) membranes. Membranes have been synthesized by grafting of styrene on FEP films followed by sulfonation. These membranes were then used to fabricate IPMCs. Chemical plating of silver has been done to form the microelectrodes. Influence of degree of grafting on actuation, surface resistance, and tensile properties of the IPMC have been evaluated. It has been observed that on increasing the degree of grafting surface resistance, tensile strength, and elongation of IPMC decrease while degree of actuation and modulus increase. V
Journal of Applied Polymer Science, 2008
A wide range of solvents have been examined to find their effect on radiation-induced grafting of... more A wide range of solvents have been examined to find their effect on radiation-induced grafting of 4-vinyl pyridine onto fluorinated ethylene propylene copolymer by simultaneous irradiation technique. The effect of solvent on percentage of grafting has been monitored by varying monomer concentration and total dose of radiation. Further grafting results have been correlated with the solubility parameter of the solvent and solvent mixtures. Evidence of grafting has been based on characterization of grafted samples in terms of FTIR, EDAX, X-ray mapping, thermogravimetric analysis, and dynamic mechanical analysis. Depth profiling of a few representative grafted films were studied by viewing the cross-sectional distribution of elemental nitrogen using SEM-EDAX. The results suggest that with increase in grafting the grafting front propagates from the surface toward bulk, thus establishing the frontal mechanism of radiation grafting. Furthermore, the grafted films were characterized for their surface properties using contact angle goniometry.
Journal of Applied Polymer Science, 1997
The synthesis of carboxyl-terminated poly(ethylene glycol adipate) (CTPA) and amine-terminated po... more The synthesis of carboxyl-terminated poly(ethylene glycol adipate) (CTPA) and amine-terminated poly(amide sulfone) (ATPS) based on the CTPA and 4,4′-diaminodiphenyl sulfone (DDS) is described. The products were characterized by IR and 13C-NMR spectroscopic analysis, nonaqueous titration, viscosity measurement, and solubility characteristics. The developed ATPS was incorporated as a modifier into the epoxy matrix and its effect was studied by DSC and DMTA. It was found that ATPS forms a compatible blend with epoxy and imparts flexibility to the epoxy matrix. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:901–907, 1997
![Research paper thumbnail of All solid supercapacitor based on polyaniline and crosslinked sulfonated poly[ether ether ketone]](https://attachments.academia-assets.com/103281794/thumbnails/1.jpg)
](Electrochimica Acta, 2010
All solid supercapacitor based on polyaniline (PANI) and crosslinked sulfonated poly[ether ether ... more All solid supercapacitor based on polyaniline (PANI) and crosslinked sulfonated poly[ether ether ketone] (XSPEEK,) is reported in this paper. The crosslinker used for sulfonated poly[ether ether ketone] (SPEEK) is 1,4-bis(hydroxymethyl) benzene. The XSPEEK is used as both solid electrolyte and separator membrane. Supercapacitors are fabricated using various PANI/XSPEEK weight ratios. These are characterized by cyclic voltammetry and galvanostatic charge-discharge studies. The supercapacitor with PANI/XSPEEK weight ratio 1:0.5, exhibit a specific capacitance of 480 F g −1 of PANI. To the best of authors' knowledge, the value reported here is the highest for a supercapacitor based on a proton conducting solid polymer electrolyte and PANI. Detailed electrochemical impedance spectroscopy analysis is carried out. The analysis shows that the complex capacitance of the supercapacitor depends on the XSPEEK content. The time constant (t 0), derived from the imaginary part of complex capacitance decreases with increase in the XSPEEK content in the supercapacitor. Cycle life characteristics of the supercapacitor show a decrease in specific capacitance during initial cycles and get stabilized during later cycles.
CRC Press eBooks, Mar 23, 2022
Journal of Coatings Technology and Research, 2021
It is well established that crosslinked polydimethylsiloxane (PDMS) based coatings have efficacio... more It is well established that crosslinked polydimethylsiloxane (PDMS) based coatings have efficacious foul release characteristics. However, a trade-off between mechanical integrity of filled and crosslinked PDMS based coatings and their foul release performance has been a bottleneck for producing efficient and durable coatings. In the present study, we report a dual approach of nano-reinforcement of a bimodal PDMS network as a strategy to produce simultaneously reinforced and toughened PDMS networks with facile release of macrofoulants from their surfaces. The nanocomposites of both unimodal and bimodal PDMS networks were prepared using oligomeric dihydroxyl functional PDMS precursor chains differing in their molecular weights by a factor of five and commercial Cloisite-20A nanoclay as the nanofiller. The clay layers were found to be mildly intercalated in the PDMS matrix, as revealed from investigations by scattering and imaging techniques at different length scales. While the unimodal PDMS networks did show nanoclay induced simultaneous reinforcement and toughening, at equivalent clay loadings, the bimodal PDMS nanocomposites seemed to stretch further with characteristic strain hardening before fracture. Dynamic mechanical analysis (DMA) and swelling studies of the nancomposites further confirmed the nanoclay induced reinforcement effect of the bimodal PDMS host matrix. The intrinsic low surface energy characteristics of PDMS were retained by bimodal blending of long and short chains and its subsequent nano-reinforcement. Macrofouling studies by panel immersion and release force measurements revealed that the macrofoulants could be dislodged from the nanocomposite coatings with a shear force < 0.05 MPa.
Journal of Physics: Conference Series, 2015
The effect of nanoclay dispersion on the thermo-mechanical properties of an unsaturated polyester... more The effect of nanoclay dispersion on the thermo-mechanical properties of an unsaturated polyester thermoset resin was studied by flexural and dynamic mechanical property measurements. Transmission electron microscopy studies revealed intercalated clay dispersion morphology in the nanocomposites. The thermomechanical measurements showed a steady decrease in the flexural strength and a relaxation temperature, with only moderate increase in the storage modulus at 1% clay loading, followed by a drop at higher clay loadings. In order to understand the absence of nano-effect in this case, free volume measurements were carried out by using positron annihilation lifetime spectroscopy. A bimodal distribution of o-Ps life times was observed. Nanoclay loading resulted in the increase of the o-Ps intensity corresponding to the longest life time as well as free volume fraction suggesting diminished chain packing efficiency in the nanocomposites. We posit that nanoclay induced decreased chain packing efficiency and the presence of higher free volume size elements might cause deterioration in mechanical properties of the nanocomposites.
Progress in Organic Coatings, 2016
Abstract A series of segmented polydimethylsiloxane based poly(urethane-urea) copolymers (PDMSPU)... more Abstract A series of segmented polydimethylsiloxane based poly(urethane-urea) copolymers (PDMSPU) of varied hard segment contents were prepared by moisture curing prepolymers of isophorone diisocyanate capped polydimethylsiloxane. Quantitative analysis of hydrogen bonding characteristics of the segmented copolymers was conducted by using Fourier transform infrared spectroscopy (FTIR). The carbonyl stretching bands were deconvoluted into components corresponding to different free and hydrogen bonded groups. The studies revealed the presence of unusually ordered urea domains in the segmented copolymers evidenced from peaks at 1622–1632 cm −1 , despite hitherto reported constraints to such ordered domain formation in these copolymers. This in turn manifested in the appearance of crystalline peaks in the wide angle X-ray diffraction (WAXD) profiles of the copolymers, which could also be directly visualized by scanning electron microscopy (SEM) and polarized optical microscopy (POM) studies. The effect of these morphological features on the thermomechanical properties of the segmented copolymers was investigated by dynamic mechanical analysis, tensile testing and hardness measurements. A good correlation between the hydrogen bonding characteristics and thermomechanical properties of the copolymers could be established.
ABSTRACT A basis for quantitative analysis of the reinforcement mechanism of polyurethane-urea/cl... more ABSTRACT A basis for quantitative analysis of the reinforcement mechanism of polyurethane-urea/clay nanocomposites using two characterization methods, positron annihilation life time spectroscopy (PALS) and dynamic mechanical analysis (DMA) is provided. DMA was used to measure the constrained volume fraction of amorphous soft segments induced by nanoclay and the storage modulus of the nanocomposites. The interfacial interactions in the nanocomposites were investigated by PALS. The modulus enhancement of the organoclay nanocomposites was found to have a good correlation with the volume fraction of the constrained region and the interfacial interactions.
AIP Conference Proceedings, 2010
... Pushkar N. Patil, SK Rath, K. Sudarshan, D. Dutta, M. Patri, PK Pujari. Abstract. ... The wat... more ... Pushkar N. Patil, SK Rath, K. Sudarshan, D. Dutta, M. Patri, PK Pujari. Abstract. ... The water uptake by the polymer is influenced by free volumes, the chemical nature and the segmental relaxation in between the molecular chains. Keywords. Solids (rheology). ...
Structural features of polyurethane-urea (PUU)/organoclay nanocomposites have been investigated b... more Structural features of polyurethane-urea (PUU)/organoclay nanocomposites have been investigated by FTIR and small angle x-ray scattering techniques. It is found that the clay has significant influence on morphology of the hard segments (HS) of the PUU. The HS domains which have rough surface, becomes more compact with mass fractal morphology with increase of clay content. FTIR suggests the clay interacts
Radiation Physics and Chemistry, 2010
Acrylic acid (AA) was grafted onto PET films by preirradiation method using a 60 Co g-radiation s... more Acrylic acid (AA) was grafted onto PET films by preirradiation method using a 60 Co g-radiation source. Microstructural investigation of the PET-g-AA copolymers has been carried out by wide angle X-ray diffraction (WAXD), dynamic mechanical analysis (DMA) and positron annihilation lifetime spectroscopy (PALS) techniques. The WAXD results showed only marginal variation in the crystallinity of the graft copolymers. Dynamic mechanical analysis showed an increase in the temperature of the arelaxation and the tan d value of subroom temperature secondary relaxations. From the PALS results, a complex variation of the free volume parameters, i.e. the o-positronium lifetime (t 3), its intensity (I 3), fractional free volume (f v) and the intermediate lifetime component was observed for the graft copolymers. Multiple phenomena of the effect of secondary relaxations, additive behavior of the individual polymer free volume parameters and effects from interfacial defects have been invoked to understand the fluctuational nature of the free volume properties in the graft copolymers.
Progress in Organic Coatings, 2010
Application of polymeric coatings is one of the methods for protection of mild steel against corr... more Application of polymeric coatings is one of the methods for protection of mild steel against corrosion. In the present work, blends of different grades of ethylene vinyl acetate (EVA) with varying vinyl acetate (VAc) content viz. 18%, 28%, 40% and hydrolyzed EVA ie, ethylene ...
Progress in Organic Coatings, 2009
Dispersion of nanoclay (NC) in polymer blend system is governed by the sequence of addition of di... more Dispersion of nanoclay (NC) in polymer blend system is governed by the sequence of addition of different ingredients. In the present work nanoclay was added in different sequences to blend composition such as ethylene vinyl acetate (EVA)/low density ...
Progress in Organic Coatings, 2008
Ethylene vinyl acetate (EVA) copolymer with varying vinyl acetate (VAc) content, viz. 18%, 28% an... more Ethylene vinyl acetate (EVA) copolymer with varying vinyl acetate (VAc) content, viz. 18%, 28% and 40% has been hydrolyzed using alcoholic NaOH solution. Fourier Transform Infrared Spectroscopy (FTIR) analyses of hydrolyzed polymer showed the presence of ...
Progress in Organic Coatings, 2008
Effect of catalysts on curing behaviour, phase morphology and surface properties of a moisture cu... more Effect of catalysts on curing behaviour, phase morphology and surface properties of a moisture cured polyurethane-urea (MCPU) coating has been studied. The prepolymer, prepared by capping hydroxy terminated polybutadiene (HTPB) with isophorone diisocyanate (IPDI), was cured with moisture using different urethane catalysts at 30°C and relative humidity of 60%. Fourier transform infrared spectroscopy (FTIR) was used to monitor the curing
Progress in Organic Coatings, 2009
... SK Rath a , JG Chavan a , S. Sasane a , Alips Srivastava a , M. Patri a , AB Samui a , Corres... more ... SK Rath a , JG Chavan a , S. Sasane a , Alips Srivastava a , M. Patri a , AB Samui a , Corresponding Author Contact Information , E-mail The Corresponding ... Diglycidyl ether of neopentyl glycol, XR-87 (epoxy equivalent weight 180 ± 5 g/equiv.), was purchased from Atul ...
Polymers for Advanced Technologies, 2004
A Novel solid polymer electrolyte (SPE) membrane containing both COOH and SO3H group has been p... more A Novel solid polymer electrolyte (SPE) membrane containing both COOH and SO3H group has been prepared by simultaneous method of radiation grafting of acrylic acid onto FEP followed by sulfonation. The presence of weakly acidic acrylic acid controls the swelling in water ...
Journal of Polymer Engineering, 1991
2 Introduction 3 Procedure 4 Conditions 4 Appearance 4 Characterization 4 Glass Transition Temper... more 2 Introduction 3 Procedure 4 Conditions 4 Appearance 4 Characterization 4 Glass Transition Temperature (Tg) 6 Polymer Melting Temperature (PMT) 8 Thermogravimetric Studies 9 Flammability Characteristics 11 Electrical Properties 12 Application 13 PVC Plasticization 14 Coating 15 Conclusion 16 References 17 VoL 10, Nos. 1-3,1991 Halogenation of Atactic Polypropylene
Journal of Membrane Science, 2011
Cross-linked sulfonated poly (ether ether ketone) (SPEEK)/reactive organoclay (Cloisite-30B) nano... more Cross-linked sulfonated poly (ether ether ketone) (SPEEK)/reactive organoclay (Cloisite-30B) nanocomposite membranes were fabricated using 1,4-bis (hydroxymethyl) benzene (BHMB) as cross-linker and Cloisite-30B organoclay as the pseudo cross-linker. The cross-linked SPEEK/clay nanocomposite membranes were prepared via solution intercalation method. Participation of reactive organoclay in the cross-linking process was established from ion exchange capacity (IEC) measurements and FTIR studies. Wide angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM) confirmed mixed clay dispersion morphology of intercalation and partial exfoliation of the clay platelets in the crosslinked SPEEK/clay nanocomposite membrane. The cross-linked SPEEK/clay nanocomposite membranes were characterized for their thermal and physical properties as a function of clay loading. The characteristics of the cross-linked nanocomposite membranes were then compared with pristine SPEEK membrane. The membrane stability, i.e. liquid uptake in water and in aqueous methanol solution, oxidative stability as well as mechanical and thermal stability were found to significantly improve with incorporation of reactive organoclay into the cross-linked SPEEK polymer matrix, without affecting the protonic conductivity appreciably.
Journal of Applied Polymer Science, 2008
Ionic polymer-metal composites have been made from radiation grafted fluorinated ethylene propyle... more Ionic polymer-metal composites have been made from radiation grafted fluorinated ethylene propylene (FEP) membranes. Membranes have been synthesized by grafting of styrene on FEP films followed by sulfonation. These membranes were then used to fabricate IPMCs. Chemical plating of silver has been done to form the microelectrodes. Influence of degree of grafting on actuation, surface resistance, and tensile properties of the IPMC have been evaluated. It has been observed that on increasing the degree of grafting surface resistance, tensile strength, and elongation of IPMC decrease while degree of actuation and modulus increase. V
Journal of Applied Polymer Science, 2008
A wide range of solvents have been examined to find their effect on radiation-induced grafting of... more A wide range of solvents have been examined to find their effect on radiation-induced grafting of 4-vinyl pyridine onto fluorinated ethylene propylene copolymer by simultaneous irradiation technique. The effect of solvent on percentage of grafting has been monitored by varying monomer concentration and total dose of radiation. Further grafting results have been correlated with the solubility parameter of the solvent and solvent mixtures. Evidence of grafting has been based on characterization of grafted samples in terms of FTIR, EDAX, X-ray mapping, thermogravimetric analysis, and dynamic mechanical analysis. Depth profiling of a few representative grafted films were studied by viewing the cross-sectional distribution of elemental nitrogen using SEM-EDAX. The results suggest that with increase in grafting the grafting front propagates from the surface toward bulk, thus establishing the frontal mechanism of radiation grafting. Furthermore, the grafted films were characterized for their surface properties using contact angle goniometry.
Journal of Applied Polymer Science, 1997
The synthesis of carboxyl-terminated poly(ethylene glycol adipate) (CTPA) and amine-terminated po... more The synthesis of carboxyl-terminated poly(ethylene glycol adipate) (CTPA) and amine-terminated poly(amide sulfone) (ATPS) based on the CTPA and 4,4′-diaminodiphenyl sulfone (DDS) is described. The products were characterized by IR and 13C-NMR spectroscopic analysis, nonaqueous titration, viscosity measurement, and solubility characteristics. The developed ATPS was incorporated as a modifier into the epoxy matrix and its effect was studied by DSC and DMTA. It was found that ATPS forms a compatible blend with epoxy and imparts flexibility to the epoxy matrix. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:901–907, 1997
Electrochimica Acta, 2010
All solid supercapacitor based on polyaniline (PANI) and crosslinked sulfonated poly[ether ether ... more All solid supercapacitor based on polyaniline (PANI) and crosslinked sulfonated poly[ether ether ketone] (XSPEEK,) is reported in this paper. The crosslinker used for sulfonated poly[ether ether ketone] (SPEEK) is 1,4-bis(hydroxymethyl) benzene. The XSPEEK is used as both solid electrolyte and separator membrane. Supercapacitors are fabricated using various PANI/XSPEEK weight ratios. These are characterized by cyclic voltammetry and galvanostatic charge-discharge studies. The supercapacitor with PANI/XSPEEK weight ratio 1:0.5, exhibit a specific capacitance of 480 F g −1 of PANI. To the best of authors' knowledge, the value reported here is the highest for a supercapacitor based on a proton conducting solid polymer electrolyte and PANI. Detailed electrochemical impedance spectroscopy analysis is carried out. The analysis shows that the complex capacitance of the supercapacitor depends on the XSPEEK content. The time constant (t 0), derived from the imaginary part of complex capacitance decreases with increase in the XSPEEK content in the supercapacitor. Cycle life characteristics of the supercapacitor show a decrease in specific capacitance during initial cycles and get stabilized during later cycles.