Monodispersed polystyrene latexes (100~500 nm) were prepared using seed emulsion polymerization.Hard and ordered polystyrene colloidal crystals were obtained by ambient drying the monodispersed polystyrene dispersion...Monodispersed polystyrene latexes (100~500 nm) were prepared using seed emulsion polymerization.Hard and ordered polystyrene colloidal crystals were obtained by ambient drying the monodispersed polystyrene dispersions.Polystyrene colloidal crystals were chemically modified by controlled sulfonation with sulfuric acid to derive a novel macro ordered hydrogels including ordered hydrogels and core/shell hydrogels,in which sulfuric acid and sulfone groups are responsible for the hydrophilic and crosslinking performances,respectively.The chemical structure and morphologies of the hydrogels were characterized by FT IR.It is shown that at a given concentration of sulfuric acid,the structural features of the samples are controlled by sulfonation time and temperature.The modification starts from the outer layer of polystyrene spheres of the colloidal crystals and increases both in reaction rate and sulfone group amount with temperature.A preliminary mechanism of the sulfonation process to prepare the ordered structures was proposed.展开更多
A rigid silica colloidal crystal template was formed by self assembly of the monodispersed silica dispersion prepared according to Stber method. Within the interstitial void of the template, β diketonate titanium com...A rigid silica colloidal crystal template was formed by self assembly of the monodispersed silica dispersion prepared according to Stber method. Within the interstitial void of the template, β diketonate titanium complexes[(dbm) 3Ti(OPh)/MAO] catalyzed polymerization of styrene was carried out to form syndiotactic polystyrene(sPS)/silica composites. The titled ordered macroporous syndiotactic polystyrene was achieved by chemical decomposition of the silica template with concentrated aqueous hydrofluoric acid, which was confirmed by SEM results. FTIR spectra indicated that all silica was removed from the composites in this study. DSC revealed that the as prepared macroporous sPS was significantly different from the bulk one, and the unique properties were inherent rather than from the enforcement effect by the silica template. Further investigation concerning the inherent microstrucutures about the molecular weight and its distribution, tacticity of the styrene etc . and their dependence on the confinement is in progress.展开更多
文摘Monodispersed polystyrene latexes (100~500 nm) were prepared using seed emulsion polymerization.Hard and ordered polystyrene colloidal crystals were obtained by ambient drying the monodispersed polystyrene dispersions.Polystyrene colloidal crystals were chemically modified by controlled sulfonation with sulfuric acid to derive a novel macro ordered hydrogels including ordered hydrogels and core/shell hydrogels,in which sulfuric acid and sulfone groups are responsible for the hydrophilic and crosslinking performances,respectively.The chemical structure and morphologies of the hydrogels were characterized by FT IR.It is shown that at a given concentration of sulfuric acid,the structural features of the samples are controlled by sulfonation time and temperature.The modification starts from the outer layer of polystyrene spheres of the colloidal crystals and increases both in reaction rate and sulfone group amount with temperature.A preliminary mechanism of the sulfonation process to prepare the ordered structures was proposed.
文摘A rigid silica colloidal crystal template was formed by self assembly of the monodispersed silica dispersion prepared according to Stber method. Within the interstitial void of the template, β diketonate titanium complexes[(dbm) 3Ti(OPh)/MAO] catalyzed polymerization of styrene was carried out to form syndiotactic polystyrene(sPS)/silica composites. The titled ordered macroporous syndiotactic polystyrene was achieved by chemical decomposition of the silica template with concentrated aqueous hydrofluoric acid, which was confirmed by SEM results. FTIR spectra indicated that all silica was removed from the composites in this study. DSC revealed that the as prepared macroporous sPS was significantly different from the bulk one, and the unique properties were inherent rather than from the enforcement effect by the silica template. Further investigation concerning the inherent microstrucutures about the molecular weight and its distribution, tacticity of the styrene etc . and their dependence on the confinement is in progress.
基金Supported by National Basic Research Program of China(No.2010CB933700 and 2011CBA00900)STCSM(No.09ZR1436000)the Knowledge Innovation Program of CAS(No.KSCX2-YW-G-042)
基金financially supported by the National Key Research and Development Program of China (2017YFA0206500)the National Natural Science Foundation of China (21673198, 21373008 and 21621091)
基金Project supported by the National Natural Science Foundation of China(Nos.91433204 and 51522209)the Fundamental Research Funds for the Central Universities(No.2015XZZX004-24),China