Preparation and electromagnetic interference shielding performance of epoxy composites modified with three-dimensional graphene aerogels
CHEN Yu1,2, ZHANG Dai-jun1,2, LI Jun1,2, WEN Jia-xuan1,2, CHEN Xiang-bao1,2
1. Soft Materials Technology Center, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China; 2. National Key Laboratory of Advanced Composites, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China
Abstract：Graphene aerogels/epoxy composites were prepared by vacuum-impregnated process with graphene aerogels as the functional filler and epoxy resin as polymer matrix. The changes in chemical structure of graphene aerogels during the preparation process and carbonization treatment were investigated by FT-IR, XPS and XRD. The results show that GO@PAA aerogel is prepared by the physical interaction between graphene oxide (GO) and polyamide acid (PAA). PAA will be transformed to polyimide by imidization and graphene oxide is partially reduced during the 300 ℃ thermal treatment. With the carbonation temperature increases, reduction degree of graphene sheets and the carbonation degree of polyimide are increased gradually. Meanwhile, SEM images and OM images show that graphene aerogels can also maintain the good three-dimensional network structure after carbonation treatment and vacuum impregnation. On this basis, graphene aerogels, which serve as the functional filler, taking advantage of the good three-dimensional network structure,can improve the corresponding composites with good electrical property and electromagnetic interference shielding performance. With only 6.23%(mass fraction) graphene aerogels (G@C-1100), the corresponding composites exhibit high electrical conductivity of 252 S·m-1 and an excellent electromagnetic interference shielding effectiveness of 70 dB.
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