In this work, it is shown that the advantage of using matrix-stabilized magnetic nanoparticles to obtain polymer nanocomposites based on them is that such nanoparticles retain their dispersion and stability of size and shape in the technological modes of obtaining polymer nanocomposite materials, and thus ensured stable ferro- and superparamagnetic properties of the obtained target products. For the production of films by the method of hot pressing from blanks obtained in an injection molding machine or a mechanochemical mixture, a manual electrically heated hydraulic press was used. The magnetic properties of nanocomposite samples (about 50 mg on average) were studied using a vibration magnetometer. The character of the dependence of the magnetization on the magnitude of the magnetic field confirms the ferromagnetic character of the behavior of the obtained nanocomposites. The resulting film nanocomposites exhibit ferromagnetic properties at room temperature.
In this work, devoted to the preparation and study of the properties of copper-containing nanocomposites based on linear low density polyethylene, it is shown that the composition of the resulting nanocomposite is not complicated by phase transformations during its synthesis. Varying the concentration of copper (II) formate (1.2÷50.8 wt%) makes it possible to control the size of the formed nanoparticles (10.2±2.0÷ 21.3±1,5 nm). It has been shown that the presence of Cu nanoparticles in a polymer matrix leads to a decrease in its degree of crystallinity - the value decreases from 42% for polyethylene to 37% for 3Cu / LLDPE, which is due to the restriction of the free movement of polymer chain segments by metal nanoparticles and, accordingly, the formation of a less ordered crystal structure.
In this work, the preparation of Fe3O4 nanoparticles modified with 3-aminopropyltriethoxysilane (APTES) was carried out under various synthesis modes (in air or in argon). The zeta potential and hydrodynamic diameter of Fe3O4-APTES nanoparticles were determined by the method of dynamic and electrokinetic light scattering. The effect of humic acids on the zeta potential, hydrodynamic diameter and colloidal stability of Fe3O4-APTES at different pH values was established by the method of dynamic and electrophoretic light scattering. It has been shown that changes in the conditions of the synthesis of nanoparticles of one component composition Fe3O4-APTES (argon) and Fe3O4-APTES (air) (in an inert medium and in an air atmosphere, respectively) lead to a change in the charge of the particle surface and a subsequent change in the sorption properties with respect to HA. It was demonstrated that the decisive role in the study of surface properties is played by the purification from low-molecular-weight impurities that can screen the surface of nanoparticles or bind with an indifferent electrolyte. The stage of dispersive post-preparation of samples is also important for the correct determination of the sorption capacity and hydrodynamic diameter of particles.
In this work, it is shown that the method of the in situ preparation of Cu/LLDPE by combining the formation of a composite and a nanodispersed phase in the viscous-flow state of a polymer makes it possible to achieve a uniform distribution of nanoparticles in the matrix and effectively regulate their mechanical and functional properties. The optimal concentration of Cu nanofiller was found to be 2-5%, allowing to achieve the best mechanical properties. Comparative analysis of the physical and mechanical properties of Cu/LLDPE nanocomposites obtained by various methods shows that the deformation and strength characteristics of the 3CuLLDPE nanocomposite obtained by the in situ method are improved in comparison with the properties of the 3CuLLDPE nanocomposite, prepared by ex situ method. The relationship between the filler content and the modulus of elasticity/tensile strength has been determined. With an increase in the filler content, the elastic modulus increases by 10-20%, and the tensile strength decreases by 30%. Elongation at break for samples with nanofiller content up to 3 wt. % higher than unfilled polymer
In this work, Cu/LLDPE composites are obtained and it is shown that the method of combining the formation of the composite and the nanodispersed phase in the viscous-flow state of the polymer makes it possible to achieve a uniform distribution of nanoparticles in the matrix. The dielectric properties of the composites have been investigated. A change in the mechanism of electrical conductivity was revealed when the concentration of the nanodispersed phase was varied. At low frequencies, nanocomposites of this type exhibit through conductivity. It was found that no pronounced relaxation peaks are observed in the studied polymer nanocomposites. However, at high concentrations of the added additive > 20%, two weakly pronounced peaks appear in the region of low and high temperatures, which, with increasing temperature, shift towards higher frequencies
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.