| In recent years,graphene has been widely concerned and studied by researchers,and has great application prospect in various fields due to its unique structure and excellent performers in electricity,thermotics,mechanics and photology.How to convert this excellent 2D material to practical applications is the key factor.A large number of studies have been reported in construction of practical devices through the mixing of graphene and matrix materials,so that the properties of the matrix materials can be improved.However,due to the?–?stacking interactions between graphene sheets,the excellent properties of graphene have not been showed completely.In that case,we converted graphene into 3D structure to prevent the poor dispersion,and maintain the unique properties of graphene at the same time.This 3D graphene has large specific surface area and high porosity,which shows excellent potential applications in adsorption,catalyst carrier,energy storage and other aspects.The main researches are as follows:In this paper,we prepared the 3D graphene/polypyrrole aerogel?PrGO?by the reaction of pyrrole monomer and the precursor-graphene oxide?GO?.In this reaction,GO was reduced to graphene and pyrrole was oxidized and polymerized into polypyrrole at the same time.The reaction mechanism of PrGO was further studied by SEM,FT-IR,Raman,XPS,TG and NMR.The optimum reaction conditions were determined by adjusting the reaction time,pyrrole content,and the concentration and pH of GO.The prepared PrGO present excellent electrical conductivity and liquid absorption performance,it also shows excellent potential in environmental protection and energy storage.We combined prepared PrGO aerogel with the polymer matrix-polydimethylsiloxane?PDMS?and epoxy resin?EP?by vacuum impregnation respectively.Finally,graphene/polydimethylsiloxane composites?PrGO/PDMS?with the bubble structure and 3D graphene/epoxy resin composites?PrGO/EP?was obtained,and it contains internal network structure of graphene aerogel at the same time.With this method,it can ensure most of the properties and avoid the dispersion of graphene in the graphene/polymer composites.PrGO/PDMS with different composite ratios were prepared by changing the concentration of GO and the concentration of PDMS precursor solution.It was found that the composites wrapped by PDMS has good compressibility and compressive resistance through tests,It could support nearly 200 times self-weight without compressive deformation and maintain stable electrical response during cyclic compression.This hydrophobic PDMS on the graphene layers and the dense network structure of composite also result in the super hydrophobic property of PrGO/PDMS.In order to show the impacts of graphene dispersion on graphene/epoxy resin composites and certify the importance of the graphene aerogel network structure in the composites.Electrical conductivity and thermal conductivity of PrGO/EP were compared with that of graphene nanoplates/epoxy resin composites?GNPs/EP?at the same filler contents.We found that PrGO/EP with low filler contents have excellent electric conductivity while GNPs/EP is insulating.With the filler content of 0.90 wt%,PrGO/EP composite has the highest conductivity of 4.7*10-2 S/m,and highest thermal conductivity of 0.589 W/?m·K?which was 28.88%higher than that of pure epoxy resin.This PrGO/EP composite prepared by pre-constructed has important and broad application in solving the overheating of present electronic devices. |
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