Al2O3 (aluminum dioxide) has a high band gap 9 eV, a high breakdown electric field 5–30 MV/cm,7 a high relative permittivity 8.6–10, high thermal stability up to at least 1000 °C, and remains amor- phous under typical processing conditions. 
PVC (Polyvinyl chloride (PVC)) ‘s use as an electrical tape backing is largely due to its dielectric strength, which can reach nearly 60 MV/cm depending on material composition. Dielectric breakdown is the voltage limit above which a short circuit may occur across the tape. 
PET (polyethylene terephthalate) has a relative permittivity 2.1-3.5. 
- Wu, Y.Q., Lin, H.C., Ye, P.D. and Wilk, G.D., 2007. Current transport and maximum dielectric strength of atomic-layer-deposited ultrathin Al 2 O 3 on GaAs. Applied physics letters, 90(7), p.072105.
- Ulrych, J., Polanský, R. and Pihera, J., 2014, May. Dielectric analysis of polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) films. In Proceedings of the 2014 15th International Scientific Conference on Electric Power Engineering (EPE) (pp. 411-415). IEEE.