Enhancement on the permeation performance of polyimide mixed matrix membranes by incorporation of gr

Enhancement on the permeation performance of polyimide mixed matrix membranes by incorporation of graphene oxide with different oxidation degreesEnhancementonthepermeationperformanceofpolyimidemixedmatrixmembranesbyincorporationofgrapheneoxidewithdifferentoxidationdegreesLiZhao,ChengCheng,Yu-FeiChen,TingWang,Chun-HuiDuandLi-GuangWu*Grapheneoxide(GO)withdifferentoxidationdegreesweresynthesizedbyharshoxidationofgraphiteusingtheimprovedHummersmethod.TheGO/polyimide(PI)mixedmatrixmembranewassuccessfullyfabricatedbyinsitupolymerizationofPImonomers(3,3′,4,4′-biphenyltetracarboxylicdianhydrideand4,4′-diaminodiphenylether)withGO.ThestructureofGOwascharacterizedbyFouriertransforminfrared,transmissionelectronmicroscopy,atomicforcemicroscopy,X-raydiffraction,andthermalgravimetricanalysis–differentialthermalanalysis.TheperformanceofdifferentGO/PImixedmatrixmembraneswasevaluatedbypermeationexperimentsofCO2/N2gasmixture(volumeratio,1:9).ResultsshowedthatmorepolarfunctionalgroupswereintroducedtoGOwit