Study On The Properties Of Polyhedral Oligonmeric Silsesquioxane(POSS) Modified Meta-aramid Insulation Paper

With the transmission network begins to turn to the direction of "ultra-high voltage,large capacity and long distance",the oil paper insulation system inside the transformer,as the core equipment of ultra-high voltage DC/AC transmission,will face more difficult challenges.Meta-aramid insulation paper is more suitable for the development of transformers because of its good thermal stability,electrical insulation,corrosion resistance,flame retardancy and other performance advantages.Therefore,research on meta-aramid insulation paper materials with excellent comprehensive properties has important application prospects.However,due to technical confidentiality and market monopoly,there is still a gap between the performance of PMIA insulation paper made in China and the analogous type of foreign insulation paper.The vigorous development of nanotechnology has provided a broader development for the cross-cutting issues in the field of electrical insulation and materials.The study of micro theory and macro performance has important scientific significance and engineering value.Firstly,two functional groups,methyl and phenyl,were attached to the polyhedral oligonmeric silsesquioxane(POSS).Through the comprehensive analysis of micro parameters and macro experimental phenomena,the influence mechanism of different POSS on the thermal stability of PMIA insulation paper was studied.Secondly,based on the results of the previous step,the combination of molecular dynamics simulation and macro characterization was used to study the effects of POSS with two different structures,cage-type and half-cage-type,on the thermal stability,mechanical properties,and electrical properties of PMIA insulation paper.Finally,the effects of different forms of POSS on the thermal stability,mechanical properties,and electrical properties of PMIA insulation paper were investigated through molecular dynamics method.The main conclusions obtained during the research of this paper are as follows:(1).Through the combination of molecular dynamics simulation and macro characterization,the research on the effect of different functional groups of POSS on the thermal stability of PMIA insulation paper found that PMIA insulation paper modified by PPSQ is better than that modified by PMSQ.(2).The semi-cage PPSQ modified PMIA insulation paper is superior to the cage PPSQ modified PMIA insulation paper in terms of thermal,mechanical and electrical properties by the combination of molecular dynamics simulation and macro characterization.(3).The effect on different forms of POSS on the properties of PMIA insulation paper was simulated by molecular dynamics.It was concluded that PMPSQ modified PMIA insulation paper was superior to PMSQ + PPSQ in terms of thermal stability,mechanical properties and electrical properties.