Ling, LC (reprint author), Chinese Acad Sci, Key Lab Carbon Mat, Inst Coal Chem, POB 165, Taiyuan 030001, Peoples R China.
Hydrogels (HG) were prepared by the sol-gel polymerization of phenolic resole, m-cresol resole and methylolated melamine mixtures with different recipes in basic aqueous solution at 85 degreesC for 5 days. Water in the HG was displaced by acetone to obtain acetone gels (AG). Organic aerogels (OA) were obtained by drying of AG under supercritical carbon dioxide. Small angle X-ray scattering (SAXS) using synchrotron radiation as X-ray source was employed to investigate microstructure of HG, AG and OA. It is found that physical cross-linking is dominant in HG and supercritical drying of the physically dominant cross-linked gels cause the following microstructure changes: (1) random growth of large scatterers that "bury" the scattering peak; (2) shrinking of gels; (3) deswelling of gel network and (4) evolution of gel structure from tangled or rough interface to smooth or flat interface. (C) 2003 Elsevier B.V. All rights reserved.
Zhang, R,Xu, Y,Meng, QH,et al. Small angle X-ray scattering study of microstructure changes of organic hydrogels from supercritical carbon dioxide drying[J]. JOURNAL OF SUPERCRITICAL FLUIDS,2004,28(2-3):#REF!.
Zhang, R.,Xu, Y.,Meng, QH.,Zhan, L.,Li, KX.,...&董宝中.(2004).Small angle X-ray scattering study of microstructure changes of organic hydrogels from supercritical carbon dioxide drying.JOURNAL OF SUPERCRITICAL FLUIDS,28(2-3),#REF!.
Zhang, R,et al."Small angle X-ray scattering study of microstructure changes of organic hydrogels from supercritical carbon dioxide drying".JOURNAL OF SUPERCRITICAL FLUIDS 28.2-3(2004):#REF!.