Influence of Nanoparticle Surfaces on the Electrical Breakdown Strength of Nanoparticle-Filled Low-Density Polyethylene

• Published in: Journal of materials research Vol. 19; no. 3; pp. 857 - 863
• Main Authors: Ma, Dongling, Siegel, Richard W., Hong, Jung-Il, Schadler, Linda S., Mårtensson, Eva, Önneby, Carina
• Format: Journal Article
• Language: English
• Published: New York, USA Cambridge University Press 01-03-2004
• Subjects: Dielectric; Electrical properties; Nanoparticle; Electrical properties; Dielectric; Nanoparticle
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/jmr.2004.19.3.857

The electrical breakdown strength of TiO2 nanoparticle-filled low-density polyethylene (LDPE) nanocomposites was investigated. It was found that the surface water on the nanoparticles played a very important role in determining the breakdown strength. The breakdown strength at 63.2% cumulative failure probability (E0) for the composites filled with dried nanoscale TiO2 was similar to that of neat LDPE and 50% higher than that for the samples filled with as-received nanoscale TiO2. This increase was due to a better dispersion, a better interface, and a morphology change of the matrix. It was also found that surface modification of nanoscale TiO2 had a significant influence on the breakdown strength. N-(2-aminoethyl) 3-aminopropyl-trimethoxysilane (AEAPS)-coated TiO2-filled samples showed about 40% higher E0 than that of uncoated, as-received TiO2-filled samples. This was mainly due to enhanced electron scattering because of the presence of polar groups in AEAPS.