Methods for improving the dielectric properties of a polymer, and related articles and devices

An article having an energy density in the range from about 3 Joules per cubic centimeter to about 50 Joules per cubic centimeter, made by the method comprising:

• providing the polymer wherein the polymer is selected from the group consisting of a polymer having a glass transition temperature of at least about 150° C., and a polymer composite comprising at least one inorganic constituent;
• contacting a surface of the polymer in a reaction chamber with a gas plasma formed from at least one feedstock gas selected from the group consisting of oxygen, carbon tetrafluoride, nitrogen, air, ammonia, hydrogen, argon and helium, wherein the feedstock gas is directed to the surface of the polymer at a flow rate of at least about 1 standard cubic centimeter per minute;
• wherein the contact with the gas plasma is carried out for a period of time sufficient to incorporate additional chemical functionality into a surface region of the polymer film, to provide a treated polymer;
• wherein the treated polymer has a dielectric breakdown strength which is at least about 0.1 percent greater than the dielectric breakdown strength of an untreated polymer.

A capacitor having an energy density in the range from about 3 Joules per cubic centimeter to about 50 Joules per cubic centimeter, made by the method comprising:

• providing the polymer wherein the polymer is selected from the group consisting of a polymer having a glass transition temperature of at least about 150° C. and a polymer composite comprising at least one inorganic constituent;
• contacting a surface of the polymer in a reaction chamber with a gas plasma formed from at least one feedstock gas selected from the group consisting of oxygen, carbon tetrafluoride, nitrogen, air, ammonia, hydrogen, argon and helium, wherein the feedstock gas is directed to the surface of the polymer at a flow rate of at least about 1 standard cubic centimeter per minute;
• wherein the contact with the gas plasma is carried out for a period of time sufficient to incorporate additional chemical functionality into a surface region of the polymer film, to provide a treated polymer;
• wherein the treated polymer has a dielectric breakdown strength which is at least about 0.1 percent (%) greater than the dielectric breakdwon strength of an untreated polymer.

An article, having dimensions of about 10 cm to 10,000 cm in length, about 10 cm to 200 cm in width, and about 1 micron to about 20 microns in thickness, and having an energy density in the range of about 3 Joules per cubic centimeter to about 50 Joules per cubic centimeter,

• wherein the article comprises (I) at least one polymer having a glass transition temperature of at least about 150° C.;
• or (II) a polymer composite containing at least one inorganic constituent;
• and
• wherein the article contains at least one surface with a surface region which comprises chemical functionality which is different from chemical functionality present in the polymer or polymer composite;
• and wherein
• the article is characterized by a dielectric breakdown strength which is at least about 0.1 percent (%) greater than the dielectric breakdown strength of the same article which does not contain the differing chemical functionality.