Monodisperse core-shell (polystyrene/DAAM-EA-AM) emulsions were prepared by two-step seed polymerization,and crosslinked films were obtained by ambient drying the copolymerization emulsions accompanying a interfacial ...Monodisperse core-shell (polystyrene/DAAM-EA-AM) emulsions were prepared by two-step seed polymerization,and crosslinked films were obtained by ambient drying the copolymerization emulsions accompanying a interfacial crosslinking between DAAM/ADDH.The crosslinking degree increased with thermal treatment temperature and time.After alkaline hydrolysis of ester and amide groups resulting carboxylic groups,the films were transformed to be mesostructured hydrogels.The chemical composition and ordered morphologies were experimentally confirmed by FT-IR,SEM and POM.Water uptake of the hydrogels decreased with the thermal treatment time of the films,implying the crosslinking degree also increased.展开更多
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
文摘Monodisperse core-shell (polystyrene/DAAM-EA-AM) emulsions were prepared by two-step seed polymerization,and crosslinked films were obtained by ambient drying the copolymerization emulsions accompanying a interfacial crosslinking between DAAM/ADDH.The crosslinking degree increased with thermal treatment temperature and time.After alkaline hydrolysis of ester and amide groups resulting carboxylic groups,the films were transformed to be mesostructured hydrogels.The chemical composition and ordered morphologies were experimentally confirmed by FT-IR,SEM and POM.Water uptake of the hydrogels decreased with the thermal treatment time of the films,implying the crosslinking degree also increased.
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.
