Polyester and Polyesterimide Compounds with Nanofillers for Impregnating of Electrical Motors

Abstract

Polyester and polyesterimide compounds for impregnating of electrical motors were modified by incorporating of three kinds of nanofillers: zinc oxide, fumed nanosilica and titanium dioxide so as to improve their properties. Nanosized particles were added at 1 wt.% of loading and homogeneously dispersed in polyester and polyesterimide matrix. The results on mechanical, electrical and barrier properties of standard and nanofilled compounds were compared. Thermogravimetric/differential thermal analysis showed that thermal stability of nanofilled compounds was significantly higher. Also the electrical and bonding strength of nanofilled impregnating compounds increased and at the same time water absorption decreased. The highest improvement of properties owing to nanofillers was obtained in the case of nanosilica.

Impact of titanium and silica/titanium fumed oxide nanofillers on the elastic properties and thermal decomposition of a polyester resin

“…Such an asymmetrical impact of the filler on the molecular structure of the resin resulted in a reduction of V L , whereas the transversal wave velocity remained unchanged (Figure ). This indicated decreases in both М C and μ C. A decrease in V L was observed previously in nanosilica‐filled polyester resin composites, where the polyester chains were fastened to the active surface sites of the nanoparticles …”

“…It is known that concentration effects of inorganic oxide nanoparticles of a high surface‐active site number on the physical parameters of polymer composites have an unmonotonic character. For example, the addition of a small amount of nanosized SiO 2 particles into a styrene‐crosslinked polyester resin not only results in an enhancement of the composite's thermal resistance, but it is also able to either suppress or stimulate the emanation of styrene. All of these issues are induced with the same effect of polymer structure stabilization because of the fastening of both polyester macromolecular chains and styrene links to the superficial centers of SiO 2 .…”

“…6,[12][13][14][15] The unsaturated polyester resin (UPR), which belongs to thermosetting polymers, demonstrates a good combination of mechanical and electric parameters and resistivity to chemically aggressive environments, and it is a good matrix for preparing composite materials with improved functional parameters. [16][17][18][19][20][21][22][23][24][25] In addition, because of the relatively low cost of the polyester resin, its composites are promising it's the manufacture of construction components in both domestic and industrial applications. 26 It is known that concentration effects of inorganic oxide nanoparticles of a high surface-active site number on the physical parameters of polymer composites have an unmonotonic character.…”

Dielectric and morphological studies on polyester/nanosilica fume composites

“…Polyester nanocomposites10 are a class of polymers reinforced with low quantities of well‐dispersed nanoparticles that offer advantages over conventional composites. Research on polymeric nanocomposite dielectrics has been conducted for several years.…”

“…Nanoparticles have great effects on the properties and morphology of polymeric nanocomposites because of their large specific surface and high surface energy. The interactions between the polymer matrix and nanoparticles alter the polymer chemistry, that is, the chain mobility and degree of cure, and generate new trap centers in the composite, which brings about a significant change in the electrical properties 10, 11…”