▎ 摘　　要

The surface chemistry of filler is closely related to the structure and morphology of nanocomposite foams. Changing the property of filler is widely used to control the cell structures and functionalize the composite foams. Surface-functionalized graphene oxide (GO-ODA) was prepared by grafting octadecylamine (ODA) on the surface of graphene oxide (GO) to make the filler disperse better in the nanocomposites and have a strong interfacial interaction with polymer matrix. Poly(methyl methacrylate) (PMMA)/GO-ODA nanocomposite foams were obtained by solution blending and foamed using supercritical carbon dioxide (scCO(2)). Compared to neat PMMA and PMMA/GO samples, the PMMA/GO-ODA nanocomposite foams showed improved cell structures with smaller size, higher cell density and more homogeneous distribution, which should be attributed to the heterogeneous nucleation caused by well-dispersed GO-ODA nanosheets. This work not only improved the compatibility and interfacial interaction of GO with polymer matrix but also indicated that the modified GO sheets can act as ideal filler to control the cell density, size and size distribution efficiently. Copyright (C) 2015, The editorial office of Journal of Materials Science & Technology. Published by Elsevier Limited. All rights reserved.