Poly (EA-MAn-APTES)/silica hybrid materials were successfully prepared fromEthyl acrylate (EA), maleic anhydride (MAn) and tetraethoxysilane (TEOS) in the presence of acoupling agent 3-aminopropyltriethoxysilane (APTE...Poly (EA-MAn-APTES)/silica hybrid materials were successfully prepared fromEthyl acrylate (EA), maleic anhydride (MAn) and tetraethoxysilane (TEOS) in the presence of acoupling agent 3-aminopropyltriethoxysilane (APTES),by free-radical solution polymerization and insitu sol-gel process. The mass fraction of TEOS varied from 0 to 25%. The hybrid materials werecharacterized by the methods of FT-IR spectra, solvent extraction, scanning electron microscope (SEM), transmission electron microscope (TEM), differential scanning calorimetry (DSC) andthermogravimetric analysis (TGA) measuring apparatus to get their structures, gel contents,morphologies, particle sizes and thermal performances. The results show that the covalent bonds arebetween organic and inorganic phases, gel contents in the hybrid materials are much higher, theSiO_2 phase is well dispersed in the polymer matrix, silicon dioxide exist at nanoscale in thecomposites and have excellent thermal stability.展开更多
As a coupling agent,(3-aminopropyl)triethoxysilane(APTES)was used to synthesize a series of silanized waterborne polyurethanes(Si-WPUs)through the acetone process.The Fourier transform infrared spectroscopy(FTIR)toget...As a coupling agent,(3-aminopropyl)triethoxysilane(APTES)was used to synthesize a series of silanized waterborne polyurethanes(Si-WPUs)through the acetone process.The Fourier transform infrared spectroscopy(FTIR)together with the X-ray photoelectron spectroscopy(XPS)was utilized to measure both elements and structures of these samples.The scanning electron microscope(SEM)results explained that APTES would be agglomerate on the surface of WPU films when the mass fraction of the agent concentration was more than 8%.Besides,the contact angle of water(CAW)can be improved from 56.5°to 90.0°by adjusting APTES concentration in Si-WPU.The decomposition temperature of films was also improved with the increase of APTES,and a significant increase could be seen in the glass temperature from 51.00℃to 85.74℃.展开更多
The procedure to measure liposome in aqueous solution has been examined using atomic force microscope (AFM). We concluded a chemical modified silicon wafer (substrate for AFM observation of liposome) with 3-aminopropy...The procedure to measure liposome in aqueous solution has been examined using atomic force microscope (AFM). We concluded a chemical modified silicon wafer (substrate for AFM observation of liposome) with 3-aminopropyltrieth-oxysilane (APTES) which enabled us to scan anionic liposome softly in water because they were keeping structures as vesicles and stably adsorbed on the substrate by electrostatic force. From captured AFM topographic images, we counted the amount of liposome and analyzed the distribution of mean diameters, which were corrected by an approximated curve of the tip shape. We discussed the method of effective evaluation as practical analysis and its problems for robust analysis.展开更多
文摘Poly (EA-MAn-APTES)/silica hybrid materials were successfully prepared fromEthyl acrylate (EA), maleic anhydride (MAn) and tetraethoxysilane (TEOS) in the presence of acoupling agent 3-aminopropyltriethoxysilane (APTES),by free-radical solution polymerization and insitu sol-gel process. The mass fraction of TEOS varied from 0 to 25%. The hybrid materials werecharacterized by the methods of FT-IR spectra, solvent extraction, scanning electron microscope (SEM), transmission electron microscope (TEM), differential scanning calorimetry (DSC) andthermogravimetric analysis (TGA) measuring apparatus to get their structures, gel contents,morphologies, particle sizes and thermal performances. The results show that the covalent bonds arebetween organic and inorganic phases, gel contents in the hybrid materials are much higher, theSiO_2 phase is well dispersed in the polymer matrix, silicon dioxide exist at nanoscale in thecomposites and have excellent thermal stability.
基金Shanghai Undergraduate Training Program on Innovation and Entrepreneurship Grant,China(No.cs1904006)。
文摘As a coupling agent,(3-aminopropyl)triethoxysilane(APTES)was used to synthesize a series of silanized waterborne polyurethanes(Si-WPUs)through the acetone process.The Fourier transform infrared spectroscopy(FTIR)together with the X-ray photoelectron spectroscopy(XPS)was utilized to measure both elements and structures of these samples.The scanning electron microscope(SEM)results explained that APTES would be agglomerate on the surface of WPU films when the mass fraction of the agent concentration was more than 8%.Besides,the contact angle of water(CAW)can be improved from 56.5°to 90.0°by adjusting APTES concentration in Si-WPU.The decomposition temperature of films was also improved with the increase of APTES,and a significant increase could be seen in the glass temperature from 51.00℃to 85.74℃.
文摘The procedure to measure liposome in aqueous solution has been examined using atomic force microscope (AFM). We concluded a chemical modified silicon wafer (substrate for AFM observation of liposome) with 3-aminopropyltrieth-oxysilane (APTES) which enabled us to scan anionic liposome softly in water because they were keeping structures as vesicles and stably adsorbed on the substrate by electrostatic force. From captured AFM topographic images, we counted the amount of liposome and analyzed the distribution of mean diameters, which were corrected by an approximated curve of the tip shape. We discussed the method of effective evaluation as practical analysis and its problems for robust analysis.
