Eliminating the nonselective permeation path inside the mixed-matrix membranes(MMMs)is critical for fabrication of gas separation membranes.We demonstrate that by utilizing the phase separation of block copolymers,we ...Eliminating the nonselective permeation path inside the mixed-matrix membranes(MMMs)is critical for fabrication of gas separation membranes.We demonstrate that by utilizing the phase separation of block copolymers,we are able to introduce metal-organic polyhedrons(MOPs)with precise pore sizes into a polymer matrix and form an ordered layered structure.We also prove that,by arranging MOP cages into a continuous nanosheet-like layer structure,we are able to generate repeated MOP-effective pathways and deplete the MOP-free permeation pathways,thus enhancing the gas-separation efficiency of MMMs.展开更多
Oleic acid was used as surface modification agent to improve the hydrophobicity of magnetic strontium hexaferrite particles. The structure and properties of treated magnetic particles were characterized by scanning el...Oleic acid was used as surface modification agent to improve the hydrophobicity of magnetic strontium hexaferrite particles. The structure and properties of treated magnetic particles were characterized by scanning electronic microscopy （SEM）, Fourier transform infrared spectra （FTIR）, powder X-ray diffraction （XRD） and magnetic property measurement system （MPMS）. The results show that oleic acid is chemically enwrapped on the surface of SrFe12O19 particles. Magnetic particles modified by oleic acid are highly dispersible and strongly responsive to magnetism but with slight decrease in saturated magnetization. The affinity between magnetic particles and monomers is improved by surface modification, resulting in increased particle incorporation in magnetic polymeric microspheres. The surface modification mechanism of magnetic particles by oleic acid is addressed in this work.展开更多
An organic silane acrylate resin （PMBK） was synthesized by free-radical solution polymerization using methyl methacrylate, butyl acrylate and （3-methacryloxypropyl）trimethoxysilane as monomers. Aluminum （AI） par...An organic silane acrylate resin （PMBK） was synthesized by free-radical solution polymerization using methyl methacrylate, butyl acrylate and （3-methacryloxypropyl）trimethoxysilane as monomers. Aluminum （AI） particles were then encapsulated in inorganic-organic hybrid films that were prepared by hydrolysis and condensation of PMBK and tetraethyl orthosilicate （TEOS） on the surface of AI pigments. Characterization results showed that PMBK and TEOS could simultaneously hydrolyze ancl condense with hydroxyl groups on the surface of the A1 particles to form composite AI particles coated with inorganic-organic hybrid films. Compared with raw AI particles, the corrosion resistance and adhesive properties of paint films containing the composite AI particles were improved greatly, while the glossiness of the paint films decreased slightly, from 48.6° to 47.0°. In alkaline media （pH 11 ）, the volume of evolved H2 of composite AI particles was only 3.5 mL, whereas that of raw AI was 83.5 mL. The glossiness of paint films containing composite A1 particles decreased by 1.66% after immersion in alkaline media for 24h, whereas that of raw AI decreased by 14.82%. Peel-off tests of the paint films showed that the composite particles moved slightly away from the paint films. In contrast, the raw A1 particles were seriously desquamated, suggesting encapsulation of hybrid films can greatly improve the adhesive properties of A1 particles in paint films.展开更多
基金supported by Guangdong Natural Science Foundation(No.2018B030306039)the Recruitment Program of Guangdong(No.2016ZT06C322)and the 111 Project(No.B18023).
文摘Eliminating the nonselective permeation path inside the mixed-matrix membranes(MMMs)is critical for fabrication of gas separation membranes.We demonstrate that by utilizing the phase separation of block copolymers,we are able to introduce metal-organic polyhedrons(MOPs)with precise pore sizes into a polymer matrix and form an ordered layered structure.We also prove that,by arranging MOP cages into a continuous nanosheet-like layer structure,we are able to generate repeated MOP-effective pathways and deplete the MOP-free permeation pathways,thus enhancing the gas-separation efficiency of MMMs.
基金supported by Natural Science Foundation of Guangdong Province(no.04020114)Science and Technology Planning Project of Guangzhou City(2006J1-C0511).
文摘Oleic acid was used as surface modification agent to improve the hydrophobicity of magnetic strontium hexaferrite particles. The structure and properties of treated magnetic particles were characterized by scanning electronic microscopy （SEM）, Fourier transform infrared spectra （FTIR）, powder X-ray diffraction （XRD） and magnetic property measurement system （MPMS）. The results show that oleic acid is chemically enwrapped on the surface of SrFe12O19 particles. Magnetic particles modified by oleic acid are highly dispersible and strongly responsive to magnetism but with slight decrease in saturated magnetization. The affinity between magnetic particles and monomers is improved by surface modification, resulting in increased particle incorporation in magnetic polymeric microspheres. The surface modification mechanism of magnetic particles by oleic acid is addressed in this work.
基金financially supported by the Natural Science Foundation of China(Grant Nos.20976059 and 21376093)Fundamental Research Funds for the Central Universities(Grant No.2013ZZ074)
文摘An organic silane acrylate resin （PMBK） was synthesized by free-radical solution polymerization using methyl methacrylate, butyl acrylate and （3-methacryloxypropyl）trimethoxysilane as monomers. Aluminum （AI） particles were then encapsulated in inorganic-organic hybrid films that were prepared by hydrolysis and condensation of PMBK and tetraethyl orthosilicate （TEOS） on the surface of AI pigments. Characterization results showed that PMBK and TEOS could simultaneously hydrolyze ancl condense with hydroxyl groups on the surface of the A1 particles to form composite AI particles coated with inorganic-organic hybrid films. Compared with raw AI particles, the corrosion resistance and adhesive properties of paint films containing the composite AI particles were improved greatly, while the glossiness of the paint films decreased slightly, from 48.6° to 47.0°. In alkaline media （pH 11 ）, the volume of evolved H2 of composite AI particles was only 3.5 mL, whereas that of raw AI was 83.5 mL. The glossiness of paint films containing composite A1 particles decreased by 1.66% after immersion in alkaline media for 24h, whereas that of raw AI decreased by 14.82%. Peel-off tests of the paint films showed that the composite particles moved slightly away from the paint films. In contrast, the raw A1 particles were seriously desquamated, suggesting encapsulation of hybrid films can greatly improve the adhesive properties of A1 particles in paint films.
