Electrical Properties of Polyesters

Abstract

Polyesters occupy an important place in the group of polymers as engineering materials to be used in electrotechnology and electronics. These polymers are characterized by excellent electro-insulating properties, showing mechanical strength, thermal resistance, and easiness in processing at the same time. The chapter presents the behavior analysis of the following polyesters in electric field: poly(ethylene terephthalate), poly(lactic acid), and polycarbonate. The effect of polymer microstructure on electric properties is presented, including its susceptibility to polarization that makes it possible to use polyesters as electrets materials. The second trend of the study presents the possibilities of transforming the electro-insulating properties of polyester fabrics to conductive properties with the use of modern processing methods such as PVD, CVD, and digital print. The functionalization of polyester fabrics extends their application range, for example, in e-textiles and reduces the fabric susceptibility to static electricity, increasing the safety of use.

Fabrication of poly (lactic acid) foams using supercritical nitrogen

“…Electronic conduction occurs at temperatures to T g and ionic conductance at temperatures above T g . 3 As previously reported, the efficiency of electron transfer in an insulating polymer, such as PLA, is dependent on the orientation of the polymer chains, particularly with respect to the direction of applied electric field. Ordered packing of crystalline regions will facilitate the transfer of electrons more favorably than disordered amorphous regions.…”

“…An increase in electric conductance of polyesters has been obtained to provide an effective dissipation of electrostatic charges and reduce electrostatic discharges. 3 PLA is an inherent electrical insulator material, which limits its utilization in electronic parts and electronic packing and containers. The static charge easily could build upon such insulator parts by contact, so that the electrical insulator materials could produce an electrostatic discharge that may interfere with circuit operation and damage the sensitive semiconductor devices.…”

Polarization-Depolarization Current (PDC) Measurements for Volume and Surface Resistivity Analysis of Polymeric Materials

“…It should be noted that in the present work, the current ipd (measured after specified time intervals) is used instead of the polarization current ip in order to get faster and more accurate results. Furthermore, it is generally known that both volume and surface resistivity of polymeric materials might depend on electric field, temperature and humidity [17][18][19]. Thus, the experimental conditions must be considered carefully.…”