High Dielectric Constant Sulfonyl-Containing Dipolar Glass Polymers with Enhanced Orientational Polarization

Abstract

Dipolar glass (DG) polymers, which utilize sub-T g orientational polarization (T g is the glass transition temperature) to enhance dielectric constants, are promising candidates for use in advanced electronic and power applications because conduction of space charges (electrons and impurity ions) is suppressed in the glassy state, and thus, the dielectric loss is low. In this study, we studied the effects of dipole density and dipole arrangement in sulfonyl-containing side-chain DG polymers on their dielectric performance in terms of dielectric constant, energy density, and dielectric loss. Monosulfonyl (i.e., CH 3 SO 2 -) and disulfonyl [i.e., CH 3 SO 2 (CH 2 ) 3 SO 2 -] groups were quantitatively grafted to polyepichlorohydrin (monosubstitution) and poly(3,3bis(chloromethyl)oxatane) (bis-substitution), respectively, in order to vary the dipole density and dipole arrangement in the side chains. As a result of orientation polarization from highly polar sulfonyl (4.5 D) groups, these DG polymers exhibited high apparent dielectric constants (7−11.5) in the glassy state with reasonably low dissipation factors (tan δ ∼ 0.003−0.02). It was found that disulfonylated DG polymers exhibited a higher dielectric constant than monosulfonylated DG polymers because of their higher dipole densities. Meanwhile, bis-substituted DG polymers showed a higher dielectric constant than monosubstituted DG polymers. Upon high-field electric poling, reversible transitions between the low-field DG state and the high-field ferroelectric state induced double hysteresis loops, and disulfonylated DG polymers had more significant ferroelectric switching than monosulfonylated DG polymers due to stronger dipolar interactions among the disulfonyl groups. On the basis of the experimental results, monosulfonylated DG polymers, whether mono-or bis-substituted, should be more appropriate for electric energy storage applications.

Interface‐Strengthened Polymer Nanocomposites with Reduced Dielectric Relaxation Exhibit High Energy Density at Elevated Temperatures Utilizing a Facile Dual Crosslinked Network

“…First, a high‐performance polymer with reactive groups (CC), large dipole units (SO 2 , 4.5 D), and biphenyl structure (arylaryl), heat‐resistant poly(arylene ether sulfone)s (DPAES), was designed and synthesized as a matrix, which are attributed to limit molecular chains motion, enlarge dielectric constant, and thermal conductivity, respectively. [ 37,38 ] More notably, the crosslinking at the interface can reduce the defects at the interface, which can effectively inhibit the leakage current and reduce interfacial polarization, which is contributed to strengthen the electric breakdown strength and reduce energy loss. Moreover, the self‐crosslink of polymer can reduce dielectric relaxation originating from the movement of polymer chains segment at elevated temperatures and thus improve the mechanical properties and dielectric stability in a broad temperature range.…”

Differentiation of roughness and surface defect impact on dielectric strength of polymeric thin films

“…Polarisation-electric-field relationship has also been commonly used as a method in various publications to determine the dielectric strength and energy density of a polymer film [19][20][21][22][23]. However, the test results are not reflecting the impact of surface roughness because of small active electrode areas in the tests.…”

Enhanced High‐Temperature Dielectric Properties of Poly(aryl ether sulfone)/BaTiO3 Nanocomposites via Constructing Chemical Crosslinked Networks

“…In this work, a series of self-crosslinkable polymers with large dipole units (−SO 2 −, 4.5 D), [25,26] heat-resistant poly(arylene ether sulfone)s containing side propenyl groups (DPAES), are designed and synthesized as matrix, which are blended with BT nanoparticles to fabricate crosslinked polymer composites by thermal crosslinking for achieving enhanced dielectric properties at high temperatures. Herein, it is worth noting that these crosslinkable polymers do not produce by-products during the crosslinking process and the crosslinked network formed by self-crosslinking can play a confinement role on macromolecular chains motion at elevated temperatures.…”