The combined effect of them increases the dispersion of the nanoclay with the
polymer matrix. By monitoring the separation of layers (basal spacing; d 001 ), four
types of polymer nanocomposites with nanoclay are obtained (Fig. 8.13b) (Kotal and
Bhowmick 2015; Pinnavaia and Beall 2000; Chen et al. 2008).
1. If there is no change in the basal spacing with the addition of clay and clay layers
remain outside, then the PNC is conventional PNC.
2. If the basal spacing increases with nanoclay and clay layers are stacked with
polymer chain intercalated between layers, then it is called intercalated PNC.
This type of PNC leads to building up of the nanometric channels for cation
transport and disrupts the recrystallization tendency of the polymer chains.
3. If the clay layers are completely in the disordered state as well as the polymer
chains, then the PNC is exfoliated PNC. This type of PNC lowers the ion-pairing
effect.
4. If the long molecular chains get intercalated inside the two or more clay galleries,
then it is called flocculated-type PNC.
Besides this, the nanoclay such as halloysite nanotube (HN) and montmorillonite
(MMT) clay are gaining more intention in the formation of the polymer
nanocomposites, and the main influence is on the thermal, electrical, and the
mechanical properties. The interaction mechanism behind the nanoclay is the formation of the electrostatic interactions between the charges present on the nanoclay
surface and the electron-rich group of the host polymer. This interaction disrupts the
weak dipolar and van der Waals forces between clay sheets. As now polymer gets
intercalated between the clay sheets and prevents the direct impact on the polymer on
heating, the improved properties are achieved (Choudhary and Sengwa 2014;
Sengwa and Choudhary 2014a; Fan et al. 2002; Shukla and Thakur 2010; Dam
et al. 2015; Fu et al. 2016; Sharma et al. 2008).
In the formation of the PNC, preparation method plays an effective role in altering
the chain arrangement. So, Dhatarwal et al. (2017) reported the preparation of the
polymer nanocomposite (PNC) solid polymer electrolyte based on PEO–PMMA–
LiBF 4 + 10 wt.% EC and 3 wt.% MMT clay by solution cast (SC) and the ultrasonic–
microwave irradiated (US–MW) solution cast methods. XRD analysis suggests the
complete dissolution of the salt as there was no peak corresponding to the salt
(2θ ¼ 26.33
) (Figure 8.14). Pure MMT shows the peak at 2θ ¼ 7.03
(001;
plane) and is also observed in the PNC prepared by SC technique along with two
main peaks of PEO (2θ ¼ 19.43
and 2θ ¼ 23.57
).
Further, for the PNC, the MMT peak shifts toward lower angle by more than 2
as
compared to that of the pristine MMT, and the increase of the d-spacing evidence the
formation of the intercalated structure. The SC methods display the high intensity of
MMT, while US–MW methods show a diffused peak with low intensity. The former
one is evidence of the intercalated structure, while the latter one is an indication of
the exfoliated structures (Sengwa et al. 2015). It was concluded that the increased
basal spacing, crystallite size, and the relative intensities were increased for the PNC
prepared by the US–MW method. Further, from the impedance spectra, it was
founded that the conductivity was more for the intercalated-type PNC and supports
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A. Arya and A. L. Sharma
polymer matrix. By monitoring the separation of layers (basal spacing; d 001 ), four
types of polymer nanocomposites with nanoclay are obtained (Fig. 8.13b) (Kotal and
Bhowmick 2015; Pinnavaia and Beall 2000; Chen et al. 2008).
1. If there is no change in the basal spacing with the addition of clay and clay layers
remain outside, then the PNC is conventional PNC.
2. If the basal spacing increases with nanoclay and clay layers are stacked with
polymer chain intercalated between layers, then it is called intercalated PNC.
This type of PNC leads to building up of the nanometric channels for cation
transport and disrupts the recrystallization tendency of the polymer chains.
3. If the clay layers are completely in the disordered state as well as the polymer
chains, then the PNC is exfoliated PNC. This type of PNC lowers the ion-pairing
effect.
4. If the long molecular chains get intercalated inside the two or more clay galleries,
then it is called flocculated-type PNC.
Besides this, the nanoclay such as halloysite nanotube (HN) and montmorillonite
(MMT) clay are gaining more intention in the formation of the polymer
nanocomposites, and the main influence is on the thermal, electrical, and the
mechanical properties. The interaction mechanism behind the nanoclay is the formation of the electrostatic interactions between the charges present on the nanoclay
surface and the electron-rich group of the host polymer. This interaction disrupts the
weak dipolar and van der Waals forces between clay sheets. As now polymer gets
intercalated between the clay sheets and prevents the direct impact on the polymer on
heating, the improved properties are achieved (Choudhary and Sengwa 2014;
Sengwa and Choudhary 2014a; Fan et al. 2002; Shukla and Thakur 2010; Dam
et al. 2015; Fu et al. 2016; Sharma et al. 2008).
In the formation of the PNC, preparation method plays an effective role in altering
the chain arrangement. So, Dhatarwal et al. (2017) reported the preparation of the
polymer nanocomposite (PNC) solid polymer electrolyte based on PEO–PMMA–
LiBF 4 + 10 wt.% EC and 3 wt.% MMT clay by solution cast (SC) and the ultrasonic–
microwave irradiated (US–MW) solution cast methods. XRD analysis suggests the
complete dissolution of the salt as there was no peak corresponding to the salt
(2θ ¼ 26.33
) (Figure 8.14). Pure MMT shows the peak at 2θ ¼ 7.03
(001;
plane) and is also observed in the PNC prepared by SC technique along with two
main peaks of PEO (2θ ¼ 19.43
and 2θ ¼ 23.57
).
Further, for the PNC, the MMT peak shifts toward lower angle by more than 2
as
compared to that of the pristine MMT, and the increase of the d-spacing evidence the
formation of the intercalated structure. The SC methods display the high intensity of
MMT, while US–MW methods show a diffused peak with low intensity. The former
one is evidence of the intercalated structure, while the latter one is an indication of
the exfoliated structures (Sengwa et al. 2015). It was concluded that the increased
basal spacing, crystallite size, and the relative intensities were increased for the PNC
prepared by the US–MW method. Further, from the impedance spectra, it was
founded that the conductivity was more for the intercalated-type PNC and supports
292
A. Arya and A. L. Sharma