Patent ID: 8564310

Claim:
A reusable capacitive sensing element for monitoring the total polar content of an oil sample, comprising: first and second interdigitated electrodes on a first major surface of a substrate, with first and second interdigitated electrodes being separated from each other by a gap therebetween that comprises exposed first major surface of the substrate; and, a fluorinated barrier coating atop the first and second interdigitated electrodes and the exposed major surface of the substrate therebetween, wherein the fluorinated barrier coating comprises a reaction product of at least one perfluoropolyether (meth)acrylate compound that comprises at least one terminal F(CF(CF 3 )CF 2 O)aCF(CF 3 )— group and at least two (meth)acrylate groups; and wherein a averages from 4 to 15.