Three 1D coordination polymers with benzoate bridges have been assembled in the presence of 18-crown-6-ether (18C6): 1∞[Tb(PhCOO)3(H2O)(EtOH)]∙0.5(18C6) 1, 1∞[Eu(PhCOO)3(H2O)2]∙0.5(18C6) 2, 1∞[Nd(PhCOO)3(H2O)2]∙0.5(18C6) 3. Compounds 2 and 3 are isomorphous. The crown...
By the extrusion and injection technique, polymer-based composite samples (polypropylene and thermoplastic polyurethane) were obtained with BaTiO3 filler in concentrations between 0 and 35 %. Following the preliminary characterizations performed by coupled thermal analysis techniques, it was found that the composite samples obtained have thermal stability up to a temperature of about 250 oC and can be processed by extrusion at temperatures between 180 and 240oC. Above this temperature, a series of degradation processes take place by successive thermooxidation with the formation of volatile products.The electrical characterization of the composite samples was performed by the dielectric spectroscopy technique, which showed that the A tga dielectric losses increase as the BaTiO3 content of the composite increases. The maximum increase being recorded at 50 Hz (the slope A tga /% BaTiO3 about 0.003 /% BaTiO3). It was also found, that the electrical conductivity (o) of the composite increases with the increase of content in BaTiO3 so that o at 100 kHz for the composite with 35 % BaTiO3 is about 50 times higher than for the reference sample M 0 (without filler).
Samples of LDPE (low-density polyethylene) and LDPE-PANSA (low-density polyethylene -4-Amino-3-hydroxy- 1-naphthalenesulfonic acid) copolymer with Ag0.5�Ni0.5�Fe2O4 powder (as a filler) composites were developed. Following the preliminary characterizations on the thermooxidability (by thermal analysis techniques), the dielectric behavior (by dielectric spectroscopy technique), the mechanical behavior, etc. it was found that the developed materials do not show significant changes after 240 h exposure to 150 mW / m2 UV. The addition of 3wt% PANSA in LDPE has the effect of increasing the mechanical performance of polymer composites with Ag0.5�Ni0.5�Fe2O4 filler. The addition of 15 wt% ferritic powder leads to significant increases in dielectric losses (by about 100% in the case of pure LDPE and about 185% of the LDPE copolymer with 3 wt% PANSA) and to the increase of the real component of the relative permittivity (by about 34.4 % in LPDE, respectively about 36.4% in LPDE copolymer / 3% wt PANSA). Dielectric behavior of the investigated materials indicates that the effect of Ag0.5�Ni0.5�Fe2O4 powder in LDPE and of copolimer LDPE with 3 wt% PANSA consists in the increasing of the shielding efficiency of electromagnetic waves - the maximum effect being recorded in the case of the composite material with the content: LDPE 84.5 wt%, 2.5 wt% / PANSA and 13% wt% Ag0.5�Ni0.5�Fe2O4.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.