Enhanced dielectric properties of high glass transition temperature PDCPD/CNT composites by frontal ring-opening metathesis polymerization

Abstract Frontal ring-opening metathesis polymerization was used to in situ prepare polydicyclopentadiene (PDCPD)/carbon nanotubes (CNTs) and PDCPD/CNT-NH 2 composites with high glass transition temperature. Compared with PDCPD/CNT composites, PDCPD/CNT-NH 2 composites have similar dielectric constants, but their loss tangent significantly reduces. The uniform dispersion of CNT-NH 2 leads to the formation of dielectric interfacial polarization. The results of dynamic mechanical analysis (DMA) showed that the glass transition temperature ( T g ) of the composites increased with the increase of filler. With the increase of the filler, the elongation at break of the PDCPD/CNT composites decreased, while the elongation at break of PDCPD/CNT-NH 2 composites increased, reaching up to 17% because of the stronger interfacial affinity. The PDCPD/CNT-NH 2 composites exhibited high dielectric permittivity (47.5 at a frequency of 100 Hz) that originates from the interfacial polarization between PDCPD and CNT-NH 2 , and the nonconducting –NH 2 groups can prevent the conductive path of CNTs and support a low loss tangent (0.096). Graphical abstract High T g PDCPD/CNT-NH 2 composite with enhanced dielectric properties was prepared by a simple and quick one-step reaction method of FROMP. Keywords: Polydicyclopentadiene; Composites; Carbon nanotubes; Dielectric properties, Interfacial polarization