High quality methylal from non-recyclable plastic waste by an improved Catalytic Hydro-Gasification Plasma(CHGP) processBarium Titanate?Based nanodielectrics of two chemically recyclable thermosets
In this work it was investigated the role of the addition of barium titanate (BaTiO3) on electrical properties of two chemically recyclable thermosets: polyhemiaminal (PHA) and polyhexahydro?s?triazine (PHT) both fabricated from 4,4'?Oxydianiline (ODA), an ether derivative of aniline and paraformaldehyde (PF). Thermal and mechanical properties as well as chemical recyclability of the two polymers and its nanocomposites/nanodielectrics were also investigated. In addition, it is presented a quantitative analysis of the nanoparticles dispersion in the PHA/PHT_BaTiO3?based nanocomposites using TEM images and the nearest neighbor distance index (NNDi) and this index is used to analyze investigated properties in connection with the proper mechanisms. Regarding the electrical properties for both neat polymers, conductivity values in the order of 10?8 S/m at 100 Hz were observed and dielectric constant values close to 2.80 for both polymers at 1 kHz. The addition of 0.5 wt% of BaTiO3 ferroelectric nanoparticles increased about 44% the dielectric constant (1 kHz) and conductivity (102 Hz) of the PHA BaTiO3?based nanocomposite. PHA and PHT exhibited glass transition temperature (Tg) values in the range of 125?180 °C. An increase of 7 °C in the Tg was observed after the incorporation of 0.5 wt% of BaTiO3 into PHA polymer. Concerning the mechanical properties values in the range of 4.00?4.45 GPa for reduced modulus and 0.30?0.43 GPa for nanohardness for PHA and PHT polymers were observed. Independently of filler content or polymer matrix, both mechanical properties were enhanced after the addition of BaTiO3. The chemical recycling of the PHA/PHT and all nanocomposites in the initial ODA reagent after sulfuric acid treatment was successfully characterized by the NMR and FTIR techniques.This article is protected by copyright. All rights reserved.
» Author: Roger H. Bello, Jacks P. Priebe, Luiz A. F. Coelho
» Reference: doi:10.1002/pi.5755
» Publication Date: 09/12/2018
