title: Novel phase change behavior of n-eicosane in nanoporous silica: emulsion template preparation and structure characterization using small angle X-ray scattering.
abstract: Silica microcapsules with hierarchical pore structure are prepared using a one step emulsion templated hydrolysis method. Silica particles of around 100 nm with percolated nanosized pores are self-assembled into micrometer scale spherical shells. The porous structure serves as an ideal host for shape stabilization of melted organic compounds. Small angle X-ray scattering (SAXS) results show that the n-eicosane encapsulated in nanoporous silica consists of mass fractal structure with a fractal dimension of 2.1. n-Eicosane encapsulated in the nanosized pores exhibits novel phase change behavior. A large melting point drop from 37.0 to 28.8 °C is observed, which is attributed to the strong interaction between the n-eicosane molecules and the silica skeleton.
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS), College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Chongyun
authors.initials: C
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Xinxin
authors.initials: X
authors.lastname: Fan
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Wu
authors.forename: Jie
authors.initials: J
authors.lastname: Zheng
authors.forename: Xingguo
authors.initials: X
authors.lastname: Li