Graphene oxide as an anti-shrinkage additive for resorcinol-formaldehyde composite aerogels

In order to strengthen the nanostructure and suppress the collapse of nanopores of resorcinol-formaldehyde (RF) aerogels during the drying process, graphene oxide (GO) was incorporated into the RF matrix to prepare GO-RF composite aerogels by sol-gel polymerization. The influences of GO content on the sol-gel process, structure, and physical properties of RF aerogels were investigated. The morphologies of composite aerogels were characterized by scanning electron microscopy and transmission electron microscopy, and it was found that GO was well dispersed in the RF matrix. In addition, GO can obviously accelerate the gelation of the RF solution and reduce both the drying shrinkage and aerogel density. As the content of GO increased from 0 to 2 wt%, both the linear shrinkage and density of composite aerogels decreased progressively from 28.3% to 2.0% and 506 to 195 kg m(-3), respectively, implying that GO is an effective additive for inhibiting the volume shrinkage of aerogels during the drying process.