Intercalated clay structures and amorphous behavior of solution cast and melt pressed poly(ethylene oxide)–clay nanocomposites

Choudhary, Shobhna; Sengwa, R. J.

doi:10.1002/app.39898

Cited by 26 publications

(12 citation statements)

References 43 publications

(90 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Structural analysis Figure 1 shows that the XRD pattern of pure PEO has major crystalline peaks at 2h = 19.22°and 23.41°, which are corresponding to its 120 and concerted 112,032 crystalline phases, respectively [36]. The inset of Fig.…”

Section: Resultsmentioning

confidence: 99%

Dielectric dispersion and relaxation studies of melt compounded poly(ethylene oxide)/silicon dioxide nanocomposites

Choudhary

Sengwa

2015

Polym. Bull.

Self Cite

View full text Add to dashboard Cite

The polymer nanocomposite films consisted of poly(ethylene oxide) (PEO) matrix with different weight percentage concentrations of silicon dioxide (SiO 2 ) as nanofiller have been prepared by melt-pressed technique. The complex dielectric function, ac electrical conductivity, electric modulus and complex impedance spectra of the nanocomposite films have been investigated over the frequency range 20 Hz to 1 MHz, at room temperature. The real part of permittivity increases with decrease of frequency below 10 kHz, whereas these values remain almost constant in the high-frequency region. The high-frequency permittivity of these nanocomposites decreases with increase of SiO 2 concentration. The relaxation peaks are observed in dielectric loss, loss tangent and loss modulus spectra of the nanocomposites which are corresponding to the PEO segmental motion (local chain dynamics). It is found that the PEO chain dynamics is much faster in the nanocomposites as compared to that in the pristine PEO film. The real part of electrical conductivity spectra of these materials has linear behaviour of two different slopes in the frequency regions of above 10 kHz and below 1 kHz. The interactions between PEO chain and SiO 2 nanoparticles, and their effect on PEO spherulites in these nanocomposites are explored by X-ray diffraction measurements.

show abstract

Section: Resultsmentioning

confidence: 99%

Dielectric dispersion and relaxation studies of melt compounded poly(ethylene oxide)/silicon dioxide nanocomposites

Choudhary

Sengwa

2015

Polym. Bull.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Figure 1a shows that the XRD patterns of NSPE films containing 13.3 wt% LiBF 4 and 1, 3 or 5 wt% MMT exhibit the intercalated MMT peak around 5° (exact 2θ values for these NSPEs are given in Table 1). The pristine MMT exhibits (001) reflection plane peak at 7.03° [41] and this peak is observed at a lower angle (~ 5°) for NSPEs which confirms the presence of intercalated MMT phase in these NSPE materials. But the significant variation in (001) peak intensity with the increase of incorporated MMT amounts in the NSPEs also infers that beside the intercalated structures, there is also the presence of exfoliated MMT structures.…”

Section: Xrd Patternsmentioning

confidence: 58%

“…The alterations in these vibrational modes of the PEO and PMMA in their 50/50 wt% blend as can be seen from the wavenumber values marked in Fig. 3 [41] due to heterogeneous polymer chain interactions which resulted the formation of the homogeneous and miscible blend as analyzed in detail in the earlier studies [18,37,40]. The shoulders peaks at 1144 cm -1 and 1056 cm -1 in the triplet of C-O-C stretching mode and the doublets at 1361 cm -1 and 1339 cm -1 of CH 2 wagging mode in the FTIR spectrum of PEO-PMMA blend ascertain the crystalline phase of PEO structures [14,18].…”

Section: Ftir Spectramentioning

confidence: 91%

“…From the figure, it can be noted that the crystalline LiBF 4 exhibits intense characteristic diffraction peak at 2θ = 26.33° and several low-intensity peaks in the 2θ range 18°-30°. The SPE films having LiBF 4 concentrations 9.7 wt% and 13.3 wt% exhibit the less intense diffraction peaks around 19° and 23° (exact values are given in Table 1) which attribute to PEO crystallites in these SPEs because the pristine PEO has characteristic diffraction peaks at 19.22° and 23.41° corresponding to its reflection planes (120) and concerted (112),(032), respectively [21,41]. Further, it is also because the PMMA used is an amorphous material and it has no sharp crystalline diffraction peak and exhibits a broader halo [30], whereas the LiBF 4 peaks are absent due to its dissociation in the SPE and NSPE films.…”

Section: Xrd Patternsmentioning

confidence: 99%

“…Further, it is also because the PMMA used is an amorphous material and it has no sharp crystalline diffraction peak and exhibits a broader halo [30], whereas the LiBF 4 peaks are absent due to its dissociation in the SPE and NSPE films. From these XRD patterns, it can be concluded that; firstly, the added amounts of LiBF 4 for both the concentrations (i.e., 9.7 wt% and 13.3 wt%) have completely dissolved; secondly, the crystalline phase of 9.7 wt% LiBF 4 containing SPE film is relatively high as evident from its greater intensity diffraction peaks; and thirdly, the overall crystalline phase of these films is very low as inferred from the very low intensities of their diffraction peaks as compared to that of the pristine PEO peaks intensities (values of intensities I are given in Table 1 [41]) which confirm that these SPEs of different LiBF 4 concentrations are predominantly amorphous.…”

Section: Xrd Patternsmentioning

confidence: 99%

See 2 more Smart Citations

Effectively improved ionic conductivity of montmorillonite clay nanoplatelets incorporated nanocomposite solid polymer electrolytes for lithium ion-conducting devices

2018

Self Cite

View full text Add to dashboard Cite

Synergistic effects of lithium salt concentration and inorganic nanofiller incorporation on the ionic conductivity of polymer blend matrix based nanocomposite solid polymer electrolytes (NSPEs) have been examined. The montmorillonite (MMT) clay nanoplatelets incorporated NSPE films based on poly(ethylene oxide) and poly(methyl methacrylate) blend matrix with lithium tetrafluoroborate (LiBF 4) ionic salt have been prepared by the solution-cast method followed by melt-press technique. The 1, 3, and 5 wt% MMT amounts along with 13.3 wt% LiBF 4 amount as compared to the weight of polymer blend have been used for the preparation of NSPE films. X-ray diffractometer (XRD) and the Fourier transform infrared (FTIR) spectrometer have been employed for structural characterization of these NSPE films. The complex permittivity and ac electrical conductivity spectra are investigated by using the dielectric relaxation spectroscopy, whereas the electrochemical performance of these materials has been characterized by the electrochemical analyzer. The XRD patterns reveal that the NSPEs are predominantly amorphous and have the intercalated and exfoliated MMT platelets, whereas the relative changes in their FTIR spectra confirm the ion-dipolar-nanofiller interactions between the functional groups of the blended polymers, lithium ions, and the MMT nanoplatelets. The permittivity and conductivity spectra of these materials are analyzed for exploring the dominant contribution of electrode polarization and dipolar polarization in the low and high frequency regions, respectively, and the presence of relaxation processes associated with structural dynamics of the solid-state ion-dipolar complexes. It has been found that the NSPE of relatively fast polymer chain segmental dynamics exhibits higher ionic conductivity. The room temperature ionic conductivity of the 13.3 wt% LiBF 4 containing SPE is found more than two times higher as compared to that of the SPE film having 9.7 wt% LiBF 4. When the MMT is incorporated, the ionic conductivity of 13.3 wt% LiBF 4 containing NSPEs enhances by about one order of magnitude at room temperature. The dc ionic conductivity of the 13.3 wt% LiBF 4 containing SPE film is found 1 × 10-5 S/ cm at 55 °C, whereas it is 1.65 × 10-5 S/cm at 27 °C for the 5 wt% MMT incorporated NSPE film. The significantly enhanced ionic conductivity with ions transference number close to unity, high electrochemical stability voltage window and good reversibility of these NSPE materials confirm their potential applications as ion conductor/separator for the development of all-solid-state ion conducting devices and the lithium-ion batteries.

show abstract

Structural characterization of hydrophilic polymer blends/montmorillonite clay nanocomposites

Sengwa

Choudhary

2014

J of Applied Polymer Sci

Self Cite

View full text Add to dashboard Cite

The nanocomposite films comprising polymer blends of poly(vinyl alcohol) (PVA), poly(vinyl pyrrolidone) (PVP), poly(ethylene oxide) (PEO), and poly(ethylene glycol) (PEG) with montmorillonite (MMT) clay as nanofiller were prepared by aqueous solution casting method. The X‐ray diffraction studies of the PVA–x wt % MMT, (PVA–PVP)–x wt % MMT, (PVA–PEO)–x wt % MMT and (PVA–PEG)–x wt % MMT nanocomposites containing MMT concentrations x = 1, 2, 3, 5 and 10 wt % of the polymer weight were carried out in the angular range (2θ) of 3.8–30°. The values of MMT basal spacing d001, expansion of clay gallery width Wcg, d‐spacing of polymer spherulite, crystallite size L and diffraction peak intensity I were determined for these nanocomposites. The values of structural parameters reveal that the linear chain PEO and PEG in the PVA blend based nanocomposites promote the amount of MMT intercalated structures, and these structures are found relatively higher for the (PVA–PEO)–x wt % MMT nanocomposites. It is observed that the presence of bulky ester‐side group in PVP backbone restricts its intercalation, whereas the adsorption behavior of PVP on the MMT nanosheets mainly results the MMT exfoliated structures in the (PVA–PVP)–x wt % MMT nanocomposites. The crystallinities of the PEO and PEG were found low due to their blending with PVA, which further decreased anomalously with the increase of MMT concentration in the nanocomposites. The decrease of polymer crystalline phase of these materials confirmed their suitability in preparation of novel solid polymer nanocomposite electrolytes. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40617.

show abstract

Intercalated clay structures and amorphous behavior of solution cast and melt pressed poly(ethylene oxide)–clay nanocomposites

Cited by 26 publications

References 43 publications

Dielectric dispersion and relaxation studies of melt compounded poly(ethylene oxide)/silicon dioxide nanocomposites

Dielectric dispersion and relaxation studies of melt compounded poly(ethylene oxide)/silicon dioxide nanocomposites

Effectively improved ionic conductivity of montmorillonite clay nanoplatelets incorporated nanocomposite solid polymer electrolytes for lithium ion-conducting devices

Structural characterization of hydrophilic polymer blends/montmorillonite clay nanocomposites

Contact Info

Product

Resources

About