Morphology and thermal and dielectric behavior of cycloaliphatic epoxy/trimethacrylate interpenetrating polymer networks for vacuum‐pressure‐impregnation electrical insulation

Abstract

Vacuum pressure impregnation has been known as the most advanced impregnation technology that has ever been developed for large and medium highvoltage electric machines and apparatuses. We developed one new type of vacuum-pressure-impregnation resin with excellent properties by means of a novel approach based on in situ sequential interpenetrating polymer networks resulting from the curing of trimethacrylate monomer [trimethylol-1,1,1-propane trimethacrylate (TMPTMA)] and cycloaliphatic epoxy resin (CER). In this study, the influence of the concentrations of the components and their microstructures on their thermal and dielectric behaviors were investigated for the cured CER/TMPTMA systems via atomic force microscopy, dynamic mechanical analysis, thermogravimetric analysis, and dielectric analysis. The investigation results show that the addition of TMPTMA to the CER-anhydride system resulted in the formation of a uniform and compact microstructure in the cured epoxy system. This led the cured CER/TMPTMA systems to show much higher moduli in comparison with the pure CER-anhydride system. The thermogravimetric analysis results show that there existed a decreasing tendency in the maximum thermal decomposition rates of the cured CER/TMPTMA systems, which implies that the thermal stability properties improved to some extent. The dielectric analysis results show that the cured CER/TMPTMA systems displayed quite different dielectric behaviors in the wide frequency range 0.01 Hz-1 MHz and in the wide temperature range 27-250 C compared with the cured CER-anhydride system.

Influence of nano-AlN particles on thermal conductivity, thermal stability and cure behavior of cycloaliphatic epoxy/trimethacrylate system

“…TGA (a) and DTG (b) curves of the nano-AlN/epoxy/TMPTMA system position reaction of epoxy network. This was in good agreement with the results from our previous study [15,16]. In the case of A2, incorporation of this small amount of the nano-AlN filler into the epoxy/TMPTMA system slightly improves the thermal stability because it increase the temperature at 5% weight loss by about 8ºC.…”

“…Influence of nano-AlN particles on thermal conductivity, thermal stability and cure behavior of cycloaliphatic epoxy/trimethacrylate system In a previous paper, our research group have reported the preparation and characterization of epoxy/trimethylol-1,1,1-propane trimethacrylate (TMPTMA) system [15,16]. In this study, nanoAlN particles with an average particle size of 50 nm were used with epoxy/TMPTMA system as the base system.…”

Influences of Modified Sm2O3 on Thermal Stability, Mechanical and Neutron Shielding Properties of Aminophenol Trifunctional Epoxy Resin

“…In the first stage, the thermal weight loss occurred at approximately 350 °C and the weight loss step continued to 430 °C. This decomposition reaction is attributed to the decomposition reaction of the epoxy network [ 42 , 43 ]. Owing to the existence of rigid structures (i.e., a benzene ring and an epoxy group) in the resin matrix, further decomposition of the composite was hindered.…”

Enhanced thermal and mechanical properties of epoxy composites filled with hybrid filler system of aluminium nitride and boron nitride

“…The main decomposition is degraded abruptly between 280 and 410°C. This decomposition reaction is attributed to the decomposition reaction of the bisphenol‐A epoxy network . Subsequently, in the case of S35, incorporation of AlN/BN fillers into DGEBA system improves the thermal stability significantly as it increased the temperature at 5% weight loss by 56.3°C compared to neat DGEBA.…”