Synthesis of dumbbell-shaped triblock structures containing ferroelectric polymers and oligoanilines with high dielectric constants

Octaanilines onto the chain ends of the ferroelectric P(VDF-CTFE) containing complementary carboxylic acid group was successfully grafted. Esterification of terephthaloyl chloride and partial hydrolysis provided terephthalic acid mono-tert-butyl ester, which was readily transformed into the benzoyl chloride and was further subject to acylation with lithium peroxide to afford tert-butyl ester benzoyl peroxide. The functional peroxide was subsequently utilized as a free-radical initiator in the copolymerization of VDF and CTFE. The presence of tert-butyl ester terminal groups in polymer was verified in the NMR spectrum. The polymer displays a decrease of dielectric constant with the increase of frequency, which indicates the existence of strong interfacial polarization. The dielectric constant rapidly increases from 12 to 85 when the content of octaaniline reaches 10 wt%. The dielectric loss increases with the increase of the octaniline content.