Studies on Polymers Having High Dielectric Constants. IX. Blend Polymers Consisting of Highly Conducting Monomeric- TCNQ Salts and Insulating Polymers

Abstract

Highly conductive N-methylquinolinium– and quinolinium–TCNQ (tetracyanoquinodimethane) complex salts were blended with insulating polymers such as polystyrene or polysulfone to obtain polymers with high dielectric constants even in high frequency regions. Owing to the high conductivity of the conductive phase, blend polymers containing 2.2–4.6 wt% of TCNQ salts exhibit high dielectric constants (εr, 20–100) up to 1 MHz at room temperature. The relaxation frequencies of these blend polymers are thus higher, by ca. two orders of magnitude, than those of blend polymers with N-n-butylquinolinium–TCNQ complex salt with conductivities about 10−3 of the present TCNQ salts. The application of ca. 30 kV/cm of DC voltage to some of the virgin samples especially alters the resistivities of blend polymers having resistivities below 1011 Ω cm; resistivities tend to increase for those polymers having lower TCNQ salt concentrations, and to decrease for polymers with higher TCNQ salt concentrations. This application of high DC voltage renders the blend polymers excellent dielectrics whose εr and tanδ are 20–100 and 10−2–10−3 at low frequencies.