A monodispersed latex from styrene(St), methyl methacrylate(MMA) and acrylic acid(AA) was synthesized with the soap free emulsion polymerization, and the formation of colloidal crystal by evaporating the water of the ...A monodispersed latex from styrene(St), methyl methacrylate(MMA) and acrylic acid(AA) was synthesized with the soap free emulsion polymerization, and the formation of colloidal crystal by evaporating the water of the latex was investigated. It has been confirmed that there exist two array manners, i.e., hexagonal and square array, and two packing modes, i.e., hexagonal packing and face-centered cubic packing in the forming process of colloidal crystals. The square array originated from the dislocation of the particle in the hexagonal array, the area of it depends on the temperature in the forming process. At a lower temperature such as at 0 ℃, relatively large areas of square array were observed in the formed colloidal crystal.展开更多
By combining vertical deposition with micro- molding in capillaries method, we have demonstrated the two-substrate vertical deposition, an alternative and versatile procedure for fabricating high-quality stable colloi...By combining vertical deposition with micro- molding in capillaries method, we have demonstrated the two-substrate vertical deposition, an alternative and versatile procedure for fabricating high-quality stable colloidal crystal chips. Apparent bright colors, special UV-vis spectra, scan- ning electron microscopy (SEM) and atomic force micros- copy (AFM) images all prove that high-quality colloidal crystal structures are formed in between the two substrates. During the two-substrate vertical deposition for colloidal crystal chips, capillary force and evaporation of the medium are critical to the formation of the colloidal crystals; while the confinement in between two close substrates makes the resulting colloidal crystal chips more stable. Due to the ex- cellent stability, these colloidal crystal chips can be used to construct some composite optical devices via a simpler and more flexible process. Meanwhile, they can also be further used as the templates for ordered multiporous materials.展开更多
In this paper, we have successfully fabricated the colloidal crystals of monodispersed polystyrene latex. Styrene was polymerized in degassed water at 75 ℃, using potassium persulfate as an initiator. The surfactant ...In this paper, we have successfully fabricated the colloidal crystals of monodispersed polystyrene latex. Styrene was polymerized in degassed water at 75 ℃, using potassium persulfate as an initiator. The surfactant was sodium dodecyl sulfate(SDS). Firstly, the monodispersed polystyrene latex with an average diameter of some nanometers was synthesized via emulsion polymerization, then these small latex particles were used to act as seeds for further growth. The size of polystyrene latex was controlled between 50 nm and 400 nm via diversifying the condition of polymerization. The resulted emulsion solution could accumulate slowly to form three dimensional ordered structure, which was induced by capillary as the solvent evaporating at room temperature. The opal is close packed face center cubic(f.c.c) lattice of polystyrene latex. Defects such as vacancies, dislocations or grain boundaries could be obviously observed from the SEM images. Reflectance spectra showed the red shift of specular reflectivity peak for the polystyrene colloidal crystal as the size of polystyrene latex increasing. It was demonstrated that the reflectance is intrinsic property of these colloidal crystals. This provides ideal model for the research and application of photonic crystals and form useful template for growth of various ordered macroporous materials.展开更多
Structural color materials with the property of angle-independence have attracted increasing interest in recent years because of their applications in various research fields.In this paper,inspired by the anisotropic ...Structural color materials with the property of angle-independence have attracted increasing interest in recent years because of their applications in various research fields.In this paper,inspired by the anisotropic lattice microstructure of the Parides sesostris butterfly,we i present a novel angle-independent structural material by simply doping spinous pollen particles into the colloidal crystal arrays to interfere their self-assembling process.The resultant composited materials have anisotropic dose-packed colloidal crystal domains around the spikes of the pollens.These differently oriented domains could reflect the light to a wide range of viewing angles,and thus imparted the composite materials with the same wide angle of structural colors.Attractively,the materials were endowed with light-controlled reversible structural color changing behavior by incorporating photothermal responsive graphene-tagged hydrogels.These features of the bioinspired angle-independent structural color materials showed their potential values in constructing intelligent sensors,anti-counterfeiting barcode labels,and so on.展开更多
文摘A monodispersed latex from styrene(St), methyl methacrylate(MMA) and acrylic acid(AA) was synthesized with the soap free emulsion polymerization, and the formation of colloidal crystal by evaporating the water of the latex was investigated. It has been confirmed that there exist two array manners, i.e., hexagonal and square array, and two packing modes, i.e., hexagonal packing and face-centered cubic packing in the forming process of colloidal crystals. The square array originated from the dislocation of the particle in the hexagonal array, the area of it depends on the temperature in the forming process. At a lower temperature such as at 0 ℃, relatively large areas of square array were observed in the formed colloidal crystal.
基金supported by the National Natural Science Foundation of China(Grant Nos.90401020 and 200340062).
文摘By combining vertical deposition with micro- molding in capillaries method, we have demonstrated the two-substrate vertical deposition, an alternative and versatile procedure for fabricating high-quality stable colloidal crystal chips. Apparent bright colors, special UV-vis spectra, scan- ning electron microscopy (SEM) and atomic force micros- copy (AFM) images all prove that high-quality colloidal crystal structures are formed in between the two substrates. During the two-substrate vertical deposition for colloidal crystal chips, capillary force and evaporation of the medium are critical to the formation of the colloidal crystals; while the confinement in between two close substrates makes the resulting colloidal crystal chips more stable. Due to the ex- cellent stability, these colloidal crystal chips can be used to construct some composite optical devices via a simpler and more flexible process. Meanwhile, they can also be further used as the templates for ordered multiporous materials.
文摘In this paper, we have successfully fabricated the colloidal crystals of monodispersed polystyrene latex. Styrene was polymerized in degassed water at 75 ℃, using potassium persulfate as an initiator. The surfactant was sodium dodecyl sulfate(SDS). Firstly, the monodispersed polystyrene latex with an average diameter of some nanometers was synthesized via emulsion polymerization, then these small latex particles were used to act as seeds for further growth. The size of polystyrene latex was controlled between 50 nm and 400 nm via diversifying the condition of polymerization. The resulted emulsion solution could accumulate slowly to form three dimensional ordered structure, which was induced by capillary as the solvent evaporating at room temperature. The opal is close packed face center cubic(f.c.c) lattice of polystyrene latex. Defects such as vacancies, dislocations or grain boundaries could be obviously observed from the SEM images. Reflectance spectra showed the red shift of specular reflectivity peak for the polystyrene colloidal crystal as the size of polystyrene latex increasing. It was demonstrated that the reflectance is intrinsic property of these colloidal crystals. This provides ideal model for the research and application of photonic crystals and form useful template for growth of various ordered macroporous materials.
基金supported by the National Natural Science Foundation of China (Nos.21105011 and 91227124)the Natural Science Foundation of Jiangsu (No.BK2012735)the Program for Changjiang Scholars and Innovative Research Team in University (IRT1222).
文摘Structural color materials with the property of angle-independence have attracted increasing interest in recent years because of their applications in various research fields.In this paper,inspired by the anisotropic lattice microstructure of the Parides sesostris butterfly,we i present a novel angle-independent structural material by simply doping spinous pollen particles into the colloidal crystal arrays to interfere their self-assembling process.The resultant composited materials have anisotropic dose-packed colloidal crystal domains around the spikes of the pollens.These differently oriented domains could reflect the light to a wide range of viewing angles,and thus imparted the composite materials with the same wide angle of structural colors.Attractively,the materials were endowed with light-controlled reversible structural color changing behavior by incorporating photothermal responsive graphene-tagged hydrogels.These features of the bioinspired angle-independent structural color materials showed their potential values in constructing intelligent sensors,anti-counterfeiting barcode labels,and so on.
