with PEO as host matrix. The prepared films were transparent and display smooth
surface morphology with optimum content 30 wt. %. DSC analysis evidences the
single-glass transition temperature, and the absence of melting peak suggests its use
in a wide range. Also, for 1 wt. % loading, it shows a comparatively better effect in
suppressing the crystallinity as compared to nanofiller and may be due to the uniform
distribution which lowers the reorganization of polymer chains. At high content,
increase in the T g was observed and was attributed to the formation of temporary
cross-linking due to the high surface area and mobility reduces. The highest ionic
conductivity was ~10
À3 S cm
À1 (At 25
C) for 30 wt % FMS-TFSISPE (E a ¼ 26 kJ/
mol) and was ten times higher as compared to desirable limit (Fig. 8.8b). This was
improved than the nonporous silica which displays conductivity $2 Â 10
À5 S cm
À1
(At 25
C) (E a ¼ 34 kJ/mol). Also, the Li
+ transference number (t Li
+
) was $0.9 and
evidences the single-ion conductive matrix. This increase in conductivity and t Li
+
with the mesoporous silica and porous nature along with large charge carriers overall
supports the fast ion conduction. Further, mechanical properties were improved, and
modulus was 3 Â 10
4 Pa for 30 wt % FMS-TFSISPE and follows a relative trend
with T g . One attention-grabbing point was that both modulus and conductivity were
improved simultaneously. It was concluded that the well-ordered mesoporous channel (high surface area and high pore volume) in the FMS-TFSISPE nanoparticles is
superior’s candidate for fulfilling the criteria of single-ion conductor where anion is
in an immobilized state in the pore wall.
Tang et al. (2012) reported the preparation of polymer nanocomposite by dispersing the hybrid nanofiller (montmorillonite clayÀCNT hybrid fillers) into PEO–
LIClO 4 matrix. XRD analysis demonstrates the disruption of the crystallinity with
the addition of nanofiller and may be due to the alteration in polymer chain
arrangement. The FTIR evidenced the presence of strong interaction between the
polymer matrix and cation and addition of hybrid nanofiller support in the smooth
migration of the cation. The FTIR deconvolution evidence that for 10 wt. clay–CNT
highest number of free charged were available for condition (Fig. 8.9a). This
increase may be due to the negative surface charge layer on CNT and ether group
which increases the salt dissociation rate (Fig. 8.9b). Another aspect is that there may
be an increase of free volume due to less possibility of chain reorganization. This
increase in free volume is linked with faster ion mobility as evidenced by the
impedance analysis in terms of conductivity. The highest ionic conductivity was
2.07 Â 10
À5 S cm
À1 for the optimum 10 wt. % clay–CNT, and with further increase,
hybrid nanofiller aggregation occurs which lowers the conductivity value. The
mechanical strength and elongation were also much higher as compared to pure
PEO. This may be attributed to the principal characteristics of the hybrid nanofiller:
(i) high aspect ratio, and (ii) rough surface. Both parameters lead to an improved
interface between the polymer and nanofiller and hence the improved mechanical
property.
Zhao et al. (2016) reported the preparation of the composite polymer electrolyte
based on PEO–LiTFSI and Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 (LAGP) as nanofiller. The highest
ionic conductivity was 6.76 Â 10
À4 S cm
À1 (at 60
C) for LAGP-I, and it also has
smaller particle size. Further, DSC analysis shows the lowering of the glass
8 Polymer Nanocomposites: Synthesis and Characterization
285
surface morphology with optimum content 30 wt. %. DSC analysis evidences the
single-glass transition temperature, and the absence of melting peak suggests its use
in a wide range. Also, for 1 wt. % loading, it shows a comparatively better effect in
suppressing the crystallinity as compared to nanofiller and may be due to the uniform
distribution which lowers the reorganization of polymer chains. At high content,
increase in the T g was observed and was attributed to the formation of temporary
cross-linking due to the high surface area and mobility reduces. The highest ionic
conductivity was ~10
À3 S cm
À1 (At 25
C) for 30 wt % FMS-TFSISPE (E a ¼ 26 kJ/
mol) and was ten times higher as compared to desirable limit (Fig. 8.8b). This was
improved than the nonporous silica which displays conductivity $2 Â 10
À5 S cm
À1
(At 25
C) (E a ¼ 34 kJ/mol). Also, the Li
+ transference number (t Li
+
) was $0.9 and
evidences the single-ion conductive matrix. This increase in conductivity and t Li
+
with the mesoporous silica and porous nature along with large charge carriers overall
supports the fast ion conduction. Further, mechanical properties were improved, and
modulus was 3 Â 10
4 Pa for 30 wt % FMS-TFSISPE and follows a relative trend
with T g . One attention-grabbing point was that both modulus and conductivity were
improved simultaneously. It was concluded that the well-ordered mesoporous channel (high surface area and high pore volume) in the FMS-TFSISPE nanoparticles is
superior’s candidate for fulfilling the criteria of single-ion conductor where anion is
in an immobilized state in the pore wall.
Tang et al. (2012) reported the preparation of polymer nanocomposite by dispersing the hybrid nanofiller (montmorillonite clayÀCNT hybrid fillers) into PEO–
LIClO 4 matrix. XRD analysis demonstrates the disruption of the crystallinity with
the addition of nanofiller and may be due to the alteration in polymer chain
arrangement. The FTIR evidenced the presence of strong interaction between the
polymer matrix and cation and addition of hybrid nanofiller support in the smooth
migration of the cation. The FTIR deconvolution evidence that for 10 wt. clay–CNT
highest number of free charged were available for condition (Fig. 8.9a). This
increase may be due to the negative surface charge layer on CNT and ether group
which increases the salt dissociation rate (Fig. 8.9b). Another aspect is that there may
be an increase of free volume due to less possibility of chain reorganization. This
increase in free volume is linked with faster ion mobility as evidenced by the
impedance analysis in terms of conductivity. The highest ionic conductivity was
2.07 Â 10
À5 S cm
À1 for the optimum 10 wt. % clay–CNT, and with further increase,
hybrid nanofiller aggregation occurs which lowers the conductivity value. The
mechanical strength and elongation were also much higher as compared to pure
PEO. This may be attributed to the principal characteristics of the hybrid nanofiller:
(i) high aspect ratio, and (ii) rough surface. Both parameters lead to an improved
interface between the polymer and nanofiller and hence the improved mechanical
property.
Zhao et al. (2016) reported the preparation of the composite polymer electrolyte
based on PEO–LiTFSI and Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 (LAGP) as nanofiller. The highest
ionic conductivity was 6.76 Â 10
À4 S cm
À1 (at 60
C) for LAGP-I, and it also has
smaller particle size. Further, DSC analysis shows the lowering of the glass
8 Polymer Nanocomposites: Synthesis and Characterization
285