Effect of modified SiO2 fillers on properties of PMMA/ENR 50 blends electrolytes / Sharil Fadli Mohamad Zamri

The polymethyl methacrylate/50 % epoxidized natural rubber (PMMA/ENR 50) blend film was not a homogeneous blend. Therefore in this study, 15 nm (SI5) and 20 nm (S20) silicon dioxide (SiCte) fillers were added to improve the homogeneity and enhance the ionic conductivity of the nanocomposite polymer electrolytes. It was found that the phase separation and the ionic conductivity of the PMMA/ENR 50 blend have been improved when Si02 fillers were added. This indicated that SiCte fillers played an important role in producing homogenous and improving ionic conductivity nanocomposite polymer electrolytes film. The highest ionic conductivity of 5.26xl0"6 Son"1 was obtained when 5 % of S15 was added into lithium tetrafluoroborate (UBF4) doped PMMA/ENR 50 (PEL155) blend system. Therefore PEL155 film was suggested as the best film in this study. However, Si02 agglomerates can be spotted on the surface of the PEL155 film due to the formation of hydrogen bonding between the silanol (Si-OH) group of the SiCh filler with the surrounding moisture. Therefore, SI5 was treated with various concentration HC1 solutions. In was found that HC1 modified S15 (MS 15) fillers filled L1BF4 doped PMMA/ENR 50 electrolyte (PELM155) films exhibit better morphology with minimum filler agglomeration than the PEL155 film. However, their ionic conductivities were lower than the PEL155 film. This indicates that Si-OH group of the Si02 filler is crutial for helping dissociation of L1BF4 salt and needed in forming Si02 linkages that provide conducting pathway for the ion tranport in the system.