Monodispersed microsized copper oxalate particles were prepared in a segmented continuous flow tube reactor, and the effect of the main parameters such as organic additive agent, initial copper ions concentration, res...Monodispersed microsized copper oxalate particles were prepared in a segmented continuous flow tube reactor, and the effect of the main parameters such as organic additive agent, initial copper ions concentration, residence time, and segmented media on the final products were investigated experimentally. The obtained copper oxalate microsized particles were disc-like in the presence of citrate ligand,which was the shape inducer for the precipitated copper oxalate. Thermodynamic equilibrium diagrams of the Cu(Ⅱ)-oxalate-H_2O,Cu(Ⅱ)-oxalate-citrate-H_2O, and Cu(Ⅱ)-oxalate-EDTA-H_2O solution systems were drawn to estimate the possible copper species under the experimental conditions and to explain the formation mechanisms of copper oxalate particles in the segmented fluidic reactor. Both theoretical and experimental results indicated that the presence of chelating reagents such as citrate and EDTA had distinct effect on the evolution of particle shape. Air and kerosene were tested as media for the fluidic flow segmentation, and the latter was verified to better promote the growth of copper oxalate particles. The present study provides an easy method to prepare monodispersed copper oxalate microsized particles in a continuous scaling-up way, which can be utilized to prepare the precursor material for conductive inks.展开更多
Developing efficient and low-cost electrocatalysts is essential for the electroreduction of N_(2) to NH_(3).Here,highly monodispersed MoO_(3) clusters loaded on a coral-like CeO_(x)compound with abundant oxygen vacanc...Developing efficient and low-cost electrocatalysts is essential for the electroreduction of N_(2) to NH_(3).Here,highly monodispersed MoO_(3) clusters loaded on a coral-like CeO_(x)compound with abundant oxygen vacancies are successfully prepared by an impregnation-reduction method.The MoO_(3) clusters with small sizes of 2.6±0.5 nm are induced and anchored by the oxygen vacancies of CeO_(x),resulting in excellent nitrogen reduction reaction(NRR)performance.Additionally,the synergistic effects between MoO_(3) and CeO_(x)lead to a further improvement of the electrochemical performance.The as-prepared MoO_(3)-CeO_(x)catalyst shows an NH_(3) yield rate of 32.2 μg h^(-1) mg^(-1) cat and a faradaic efficiency of 7.04%at-0.75 V(vs.reversible hydrogen electrode)in 0.01 M Dulbecco’s Phosphate Buffered Saline.Moreover,it displays decent electrochemical stability over 30,000 s.Besides,the electrochemical NRR mechanism for MoO_(3)-CeO_(x)is investigated by in-situ Fourier transform infrared spectroscopy.N-H stretching,H-N-H bending,and N-N stretching are detected during the reaction,suggesting that an associative pathway is followed.This work provides an approach to designing and synthesizing potential electrocatalysts for NRR.展开更多
Spherical, monodispersed europium hydroxycarbonate particles wereobtained by homogeneous precipitation with urea in aqueous solution of Eu.(NO3)3at elevated temperature.The particles were readily converted to the unif...Spherical, monodispersed europium hydroxycarbonate particles wereobtained by homogeneous precipitation with urea in aqueous solution of Eu.(NO3)3at elevated temperature.The particles were readily converted to the uniformEu2O3 with average particle size of 50nm after calcined at 750℃.展开更多
A series of thermodynamic parameters in formation of ultrafine monodispersed colloidal particles of Y(OH)CO3 were measured, estimated and calculated. The thermodynamic stability of Y(OH)CO3 colloidal particles was stu...A series of thermodynamic parameters in formation of ultrafine monodispersed colloidal particles of Y(OH)CO3 were measured, estimated and calculated. The thermodynamic stability of Y(OH)CO3 colloidal particles was studied and discussed by phenomenological model. It is suggested that ultrafine monodispersed colloidal particles of Y(OH)CO3 are stable only in a very narrow temporary supersaturation range ( 1<x<1 .08).展开更多
Monodispersed potymeric microparticles were prepared by seed-poly- merization.High performance packings were obtained for anion chromatography by coating the surface-sutfonated partictes with quarternized latexes.
In this paper, zinc acetate, manganese acetate and thiacetamide are used as raw materials to successfully synthesize monodispersed ZnS:Mn^2+ microspheres by using hydrothermal method and taking P123 surfactant as a ...In this paper, zinc acetate, manganese acetate and thiacetamide are used as raw materials to successfully synthesize monodispersed ZnS:Mn^2+ microspheres by using hydrothermal method and taking P123 surfactant as a template. The products were characterized by XRD, STEM, FT-IR and N2 adsorption-desorption. And the results show that the diameter of this microsphere is 1.0 μm or so, which is larger than that of ZnS microsphere without Mn^2+ doping, and it has monodispersion, smooth surface and uniform size, The doping of Mn^2+ does not obviously change the structure of monodispersed ZnS microsphere. The photoluminescence peak lies in a wide band ranging from 450 to 650 nm, and the microspheres emit orange light; with the increase of Mn^2+ concentration, fluorescence intensity of ZnS:Mn^2+ microsphere changes, and when the mole ratio of Mn^2+:Zn^2+ is 0.3:1, the fluorescence intensity is the strongest.展开更多
The present, paper contains a new composite material Co;O;UFP sol prepared by using W/O microemulsion method, and its size distribution, interracial and optical nonlincar properties are discussed. The method for the p...The present, paper contains a new composite material Co;O;UFP sol prepared by using W/O microemulsion method, and its size distribution, interracial and optical nonlincar properties are discussed. The method for the preparation of UFP sol is as follows: at first, CoCl;and DBS so-展开更多
Based on the template formed from monodispersed polystyrene (PS) latex, a modified fast sol-gel process was employed to synthesize a three-dimensional ( 3-D ) ordered macroporous silica material after removing the tem...Based on the template formed from monodispersed polystyrene (PS) latex, a modified fast sol-gel process was employed to synthesize a three-dimensional ( 3-D ) ordered macroporous silica material after removing the template by calcination at high temperature. It was indicated that there existed highly ordered packed pores within the whole silica material by SEM morphology observation. It was also found that the pores were interconnected. The pore size could be controlled mainly by varying the particle size of the latex ranging from 101 to 102 nm. The formation process of the ordered pores was also preliminarily discussed.展开更多
In this paper, highly dispersive nanosized copper particles with a mean particle size of less than 6 nm are prepared by an environmentally friendly chemical reduction method. Non-toxic L-ascorbic acid acts as both red...In this paper, highly dispersive nanosized copper particles with a mean particle size of less than 6 nm are prepared by an environmentally friendly chemical reduction method. Non-toxic L-ascorbic acid acts as both reducing agent and antioxidant in ethylene glycol in the absence of any other capping agent. Transmission electron microscopy (TEM) is used to characterize the size and morphology of Cu nanoparticles. The results of UV-Vis spectroscopy (UV-Vis), energy dispersive spectroscopy (EDS) and high resolution TEM (HRTEM) illustrate that the resultant product is pure Cu nanocrystals. The size of Cu nanoparticles is remarkably impacted by the order of reagent addition, and the investigation reveals the reaction procedure of Cu^2+ ions and L-ascorbic acid.展开更多
The α-Fe_2 O_3@SiO_2 reddish pigments with core-shell structure were successfully prepared by hydrothermal and Stober methods. The structure, morphology, and chromaticity of the synthesized pigments were characterize...The α-Fe_2 O_3@SiO_2 reddish pigments with core-shell structure were successfully prepared by hydrothermal and Stober methods. The structure, morphology, and chromaticity of the synthesized pigments were characterized by XRD, SEM, TEM, FTIR, XPS, and colorimetry. The results indicated that the as-prepared pigments have the characteristics of narrow particle size distribution, high dispersion,and good sphericity. The α-Fe_2 O_3@SiO_2 reddish pigments were uniform and well dispersed in solution. In addition, the pigments with different shell thickness were also prepared, and the effect of shell thickness on the color performance of the pigments was discussed.展开更多
The preparations of superconducting thin films by DC, RF sputtering, laser evaporation and the MOCVD method have been reported. In order to extend the applications of high T<sub>c</sub> superconducting thi...The preparations of superconducting thin films by DC, RF sputtering, laser evaporation and the MOCVD method have been reported. In order to extend the applications of high T<sub>c</sub> superconducting thin films in industry, a homogeneous sol with monodispersed particles Y<sub>2</sub>O<sub>3</sub>, BaO and CuO in size of nanocrystalline 50—200 nm展开更多
A cerium-triethanolamine complex was obtained by the reaction of cerium(III) nitrate and triethanolamine in ethanol solution. Spontaneous oxidation of cerium(III) to cerium(IV) by oxygen occurred during the reaction. ...A cerium-triethanolamine complex was obtained by the reaction of cerium(III) nitrate and triethanolamine in ethanol solution. Spontaneous oxidation of cerium(III) to cerium(IV) by oxygen occurred during the reaction. The complex was crystalline and soluble in water. Nanosized ceria (CeO2) particles could be prepared via hydrolysis of the complex in aqueous solution, and the extent of agglomeration of particles increased with the increase in temperature for hydrolysis. Under the low temperature of 25 oC, mon...展开更多
Using the polymerizable hydrophobic styrene monomer as the dispersion medium and the traditional nonionic surfactant OP-10 as emulsifier, stable silver nanoparticles of narrow size distribution were prepared by a reve...Using the polymerizable hydrophobic styrene monomer as the dispersion medium and the traditional nonionic surfactant OP-10 as emulsifier, stable silver nanoparticles of narrow size distribution were prepared by a reverse (w/o) microemulsion method. The powder X-ray diffraction (XRD) pattern indicated that the obtained silver nanoparticles were of face-centered cubic structure. The results of the transmission electron microscopy (TEM) show that the final silver nanoparticles are of spherical structure with an average diameter of 15.2 nm and of a Gaussian distribution. The internal high-ordered structure of silver nanoparticles was characterized by the field-emission high-resolution transmission electron microscopy (FEHRTEM), indicating that the silver is monocrystalline and it has only one nucleation site during the formation process of a nanoparticle. The time-resolved UV-visible absorption spectra was used to monitor the process of the reaction in situ. The results show that the concentration of silver nanoparticles increases but the size changes little and the morphology transforms from obvious ellipsoidal shape to nearly spherical shape during the process. The experimental results indicate that the droplets’ dynamic exchange which is closely related to the nature of surfactant film is the control factor of the kinetics. The dynamic exchange mechanism of silver nanoparticle formation is proposed to involve continual encounter of two separate droplets forming transient fused dimer in which the chemical reaction occurs followed by re-separation without combination. Attributed to the dual role of surfactant in the nanoparticle formation, tailored nanoparticles can be successfully synthesized in control in the premise of a certain stability of reverse microemulsion.展开更多
A series of new water-soluble bifunctional comonomers having both carboxyl and alkyl polyoxyethylene groups, such as sodium mono(ethyl polyoxyethylene) maleate (ZE series) with various molecular weights of polyoxyethy...A series of new water-soluble bifunctional comonomers having both carboxyl and alkyl polyoxyethylene groups, such as sodium mono(ethyl polyoxyethylene) maleate (ZE series) with various molecular weights of polyoxyethylene ethyl ether, were synthesized and characterized. The effects of the structural factor, the amount and feeding mode of the comonomers, the initiator concentration and polymerization temperature on the stability of emulsifier-free emulsion copolymerization of methyl methacrylate (MMA) and butyl acrylate (BA) in the presence of a small amount of ZE with potassium persulfate as initiator were investigated. Stable, almost monodispersed MMA/BA/ZE emulsifier-free latex particles were prepared.展开更多
The preparation process of electrically conductive filler for anisotropic conductive adhesive was performed and discussed.The spherical filler contains tri-layer structures: resin core,Ni-P intermediate coating layer,...The preparation process of electrically conductive filler for anisotropic conductive adhesive was performed and discussed.The spherical filler contains tri-layer structures: resin core,Ni-P intermediate coating layer,Au outer coating layer.The 4 μm resin spherical cores were synthesized by monodispersion polymerization method.Then they were contributed to electrical conductivity by electrolessly plating Ni-P layer and gold layer.These particles have good corrosion resistance,high stability,and enough mechanical strength.When mixed with thermosetting epoxy resin to produce anisotropic conductive adhesive(ACA),it can realize a good conductive bonding between bumps on dies and pads on substrates.This environmentally friendly conductive material offers numerous advantages over conventional solder technology and is an ideal substitute for the lead-contained solder in electronics packaging.展开更多
Monodisperse crosslinked poly(chloromethylstyrene-co-divinylbenzene)(poly(CMSt-co-DVB))microsphereswere prepared by distillation-precipitation copolymerization of chloromethylstyrene(CMSt)and divinylbenzene(DVB)inneat...Monodisperse crosslinked poly(chloromethylstyrene-co-divinylbenzene)(poly(CMSt-co-DVB))microsphereswere prepared by distillation-precipitation copolymerization of chloromethylstyrene(CMSt)and divinylbenzene(DVB)inneat acetonitrile.The polymer particles had clean surfaces due to the absence of any added stabilizer.The size of the particlesranges from 2.59 μm to 3.19 μm and with mono-dispersity around 1.002-1.014.The effects of monomer feed incopolymerization on the microsphere formation were described.The polymer microspheres were characterized by SEM andchlorinity elemental analysis.展开更多
Monodisperse titania glycolate submicrospheres were synthesized by a modified sol-gel route, in which ultrasonic treatment was introduced to improve the reaction efficiency. The as-prepared products were characterized...Monodisperse titania glycolate submicrospheres were synthesized by a modified sol-gel route, in which ultrasonic treatment was introduced to improve the reaction efficiency. The as-prepared products were characterized by means of Fourier transform infrared spectrum (FT-IR), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results indicate that the as-prepared products are titania glycolate submicrospheres with diameters of 230-330 nm. The average particle diameter is estimated to be about 280 nm. Ultrasonic treatment has an important influence on the morphology of the produced titania glycolates. After calcination at 450°C for 2 h, these titania glycolates were completely converted into anatase TiO2. The morphology of TiO2 particles was well reserved during the calcination process except for a reduction of 18% in the average particle size.展开更多
Simultaneous achievement in high solid content and high microsphere yield is deemed a challenge in the fabrication of monodisperse microspheres by precipitation polymerization.We herein demonstrate that micro-sized mo...Simultaneous achievement in high solid content and high microsphere yield is deemed a challenge in the fabrication of monodisperse microspheres by precipitation polymerization.We herein demonstrate that micro-sized monodisperse poly(methacrylic monomer-divinylbenzene)microspheres containing epoxy,lauyl,carboxyl and hydroxyl functions can be fabricated by solvothermal precipitation copolymerization at 20%(mass)monomer loading with over 94%microsphere yield.The morphology and porosity of the obtained particles can be readily tuned by cosolvent-acetonitrile binary solvents.Addition of a small amount of cosolvent that has similar solubility parameter to that of the functional monomer can significantly improve the monodispersity of the obtained microspheres.When tetrahydrofuran was used as the co-solvent,the surface area of the highly porous microspheres achieved higher than 400 m^(2)·g^(-1).Solvothermal precipitation co-polymerization can be expected in scale-up fabrication of various monodisperse functional microspheres free of any surfactant and additive.展开更多
文摘Monodispersed microsized copper oxalate particles were prepared in a segmented continuous flow tube reactor, and the effect of the main parameters such as organic additive agent, initial copper ions concentration, residence time, and segmented media on the final products were investigated experimentally. The obtained copper oxalate microsized particles were disc-like in the presence of citrate ligand,which was the shape inducer for the precipitated copper oxalate. Thermodynamic equilibrium diagrams of the Cu(Ⅱ)-oxalate-H_2O,Cu(Ⅱ)-oxalate-citrate-H_2O, and Cu(Ⅱ)-oxalate-EDTA-H_2O solution systems were drawn to estimate the possible copper species under the experimental conditions and to explain the formation mechanisms of copper oxalate particles in the segmented fluidic reactor. Both theoretical and experimental results indicated that the presence of chelating reagents such as citrate and EDTA had distinct effect on the evolution of particle shape. Air and kerosene were tested as media for the fluidic flow segmentation, and the latter was verified to better promote the growth of copper oxalate particles. The present study provides an easy method to prepare monodispersed copper oxalate microsized particles in a continuous scaling-up way, which can be utilized to prepare the precursor material for conductive inks.
基金financially supported by the National Key Research and Development Program of China(2017YFA0206500)NSFC(Grant Nos.21673198,91934303,21621091)。
文摘Developing efficient and low-cost electrocatalysts is essential for the electroreduction of N_(2) to NH_(3).Here,highly monodispersed MoO_(3) clusters loaded on a coral-like CeO_(x)compound with abundant oxygen vacancies are successfully prepared by an impregnation-reduction method.The MoO_(3) clusters with small sizes of 2.6±0.5 nm are induced and anchored by the oxygen vacancies of CeO_(x),resulting in excellent nitrogen reduction reaction(NRR)performance.Additionally,the synergistic effects between MoO_(3) and CeO_(x)lead to a further improvement of the electrochemical performance.The as-prepared MoO_(3)-CeO_(x)catalyst shows an NH_(3) yield rate of 32.2 μg h^(-1) mg^(-1) cat and a faradaic efficiency of 7.04%at-0.75 V(vs.reversible hydrogen electrode)in 0.01 M Dulbecco’s Phosphate Buffered Saline.Moreover,it displays decent electrochemical stability over 30,000 s.Besides,the electrochemical NRR mechanism for MoO_(3)-CeO_(x)is investigated by in-situ Fourier transform infrared spectroscopy.N-H stretching,H-N-H bending,and N-N stretching are detected during the reaction,suggesting that an associative pathway is followed.This work provides an approach to designing and synthesizing potential electrocatalysts for NRR.
文摘Spherical, monodispersed europium hydroxycarbonate particles wereobtained by homogeneous precipitation with urea in aqueous solution of Eu.(NO3)3at elevated temperature.The particles were readily converted to the uniformEu2O3 with average particle size of 50nm after calcined at 750℃.
文摘A series of thermodynamic parameters in formation of ultrafine monodispersed colloidal particles of Y(OH)CO3 were measured, estimated and calculated. The thermodynamic stability of Y(OH)CO3 colloidal particles was studied and discussed by phenomenological model. It is suggested that ultrafine monodispersed colloidal particles of Y(OH)CO3 are stable only in a very narrow temporary supersaturation range ( 1<x<1 .08).
文摘Monodispersed potymeric microparticles were prepared by seed-poly- merization.High performance packings were obtained for anion chromatography by coating the surface-sutfonated partictes with quarternized latexes.
基金the Fujian Hi-tech Project Foundation (No. 2004H008)
文摘In this paper, zinc acetate, manganese acetate and thiacetamide are used as raw materials to successfully synthesize monodispersed ZnS:Mn^2+ microspheres by using hydrothermal method and taking P123 surfactant as a template. The products were characterized by XRD, STEM, FT-IR and N2 adsorption-desorption. And the results show that the diameter of this microsphere is 1.0 μm or so, which is larger than that of ZnS microsphere without Mn^2+ doping, and it has monodispersion, smooth surface and uniform size, The doping of Mn^2+ does not obviously change the structure of monodispersed ZnS microsphere. The photoluminescence peak lies in a wide band ranging from 450 to 650 nm, and the microspheres emit orange light; with the increase of Mn^2+ concentration, fluorescence intensity of ZnS:Mn^2+ microsphere changes, and when the mole ratio of Mn^2+:Zn^2+ is 0.3:1, the fluorescence intensity is the strongest.
基金Supported by the National Natural Science Foundation of China
文摘The present, paper contains a new composite material Co;O;UFP sol prepared by using W/O microemulsion method, and its size distribution, interracial and optical nonlincar properties are discussed. The method for the preparation of UFP sol is as follows: at first, CoCl;and DBS so-
文摘Based on the template formed from monodispersed polystyrene (PS) latex, a modified fast sol-gel process was employed to synthesize a three-dimensional ( 3-D ) ordered macroporous silica material after removing the template by calcination at high temperature. It was indicated that there existed highly ordered packed pores within the whole silica material by SEM morphology observation. It was also found that the pores were interconnected. The pore size could be controlled mainly by varying the particle size of the latex ranging from 101 to 102 nm. The formation process of the ordered pores was also preliminarily discussed.
基金Acknowledgement This work is sponsored by the National Natural Science Foundation of China (No. 51202175) and the Natural Science Foundation of Hubei Province (No. 2011 CDB245).
文摘In this paper, highly dispersive nanosized copper particles with a mean particle size of less than 6 nm are prepared by an environmentally friendly chemical reduction method. Non-toxic L-ascorbic acid acts as both reducing agent and antioxidant in ethylene glycol in the absence of any other capping agent. Transmission electron microscopy (TEM) is used to characterize the size and morphology of Cu nanoparticles. The results of UV-Vis spectroscopy (UV-Vis), energy dispersive spectroscopy (EDS) and high resolution TEM (HRTEM) illustrate that the resultant product is pure Cu nanocrystals. The size of Cu nanoparticles is remarkably impacted by the order of reagent addition, and the investigation reveals the reaction procedure of Cu^2+ ions and L-ascorbic acid.
基金financially supported by the Initiative Scientific Research Program from Jingdezheng Ceramic Institute and SRT Program (No. 1721T0264) from Tsinghua University
文摘The α-Fe_2 O_3@SiO_2 reddish pigments with core-shell structure were successfully prepared by hydrothermal and Stober methods. The structure, morphology, and chromaticity of the synthesized pigments were characterized by XRD, SEM, TEM, FTIR, XPS, and colorimetry. The results indicated that the as-prepared pigments have the characteristics of narrow particle size distribution, high dispersion,and good sphericity. The α-Fe_2 O_3@SiO_2 reddish pigments were uniform and well dispersed in solution. In addition, the pigments with different shell thickness were also prepared, and the effect of shell thickness on the color performance of the pigments was discussed.
基金Project supported by the National Natural Science Foundation of China.
文摘The preparations of superconducting thin films by DC, RF sputtering, laser evaporation and the MOCVD method have been reported. In order to extend the applications of high T<sub>c</sub> superconducting thin films in industry, a homogeneous sol with monodispersed particles Y<sub>2</sub>O<sub>3</sub>, BaO and CuO in size of nanocrystalline 50—200 nm
基金Project supported by the Provincal Major Science and Technology Special Projects of Zhejiang Province (2006 C11172)
文摘A cerium-triethanolamine complex was obtained by the reaction of cerium(III) nitrate and triethanolamine in ethanol solution. Spontaneous oxidation of cerium(III) to cerium(IV) by oxygen occurred during the reaction. The complex was crystalline and soluble in water. Nanosized ceria (CeO2) particles could be prepared via hydrolysis of the complex in aqueous solution, and the extent of agglomeration of particles increased with the increase in temperature for hydrolysis. Under the low temperature of 25 oC, mon...
文摘Using the polymerizable hydrophobic styrene monomer as the dispersion medium and the traditional nonionic surfactant OP-10 as emulsifier, stable silver nanoparticles of narrow size distribution were prepared by a reverse (w/o) microemulsion method. The powder X-ray diffraction (XRD) pattern indicated that the obtained silver nanoparticles were of face-centered cubic structure. The results of the transmission electron microscopy (TEM) show that the final silver nanoparticles are of spherical structure with an average diameter of 15.2 nm and of a Gaussian distribution. The internal high-ordered structure of silver nanoparticles was characterized by the field-emission high-resolution transmission electron microscopy (FEHRTEM), indicating that the silver is monocrystalline and it has only one nucleation site during the formation process of a nanoparticle. The time-resolved UV-visible absorption spectra was used to monitor the process of the reaction in situ. The results show that the concentration of silver nanoparticles increases but the size changes little and the morphology transforms from obvious ellipsoidal shape to nearly spherical shape during the process. The experimental results indicate that the droplets’ dynamic exchange which is closely related to the nature of surfactant film is the control factor of the kinetics. The dynamic exchange mechanism of silver nanoparticle formation is proposed to involve continual encounter of two separate droplets forming transient fused dimer in which the chemical reaction occurs followed by re-separation without combination. Attributed to the dual role of surfactant in the nanoparticle formation, tailored nanoparticles can be successfully synthesized in control in the premise of a certain stability of reverse microemulsion.
文摘A series of new water-soluble bifunctional comonomers having both carboxyl and alkyl polyoxyethylene groups, such as sodium mono(ethyl polyoxyethylene) maleate (ZE series) with various molecular weights of polyoxyethylene ethyl ether, were synthesized and characterized. The effects of the structural factor, the amount and feeding mode of the comonomers, the initiator concentration and polymerization temperature on the stability of emulsifier-free emulsion copolymerization of methyl methacrylate (MMA) and butyl acrylate (BA) in the presence of a small amount of ZE with potassium persulfate as initiator were investigated. Stable, almost monodispersed MMA/BA/ZE emulsifier-free latex particles were prepared.
基金The National Natural Science Foundation of China(No.10474024)NSFC-RGC Joint Research Scheme(No.60318002)+1 种基金Youth Chenguang Project of Science and Technology of Wuhan City of China(No.20065004116-10)StateKey Lab.of Advanced Technology for Materials Synthesis and Processing(Wuhan University of Technology,No.WUT2004 M08)
文摘The preparation process of electrically conductive filler for anisotropic conductive adhesive was performed and discussed.The spherical filler contains tri-layer structures: resin core,Ni-P intermediate coating layer,Au outer coating layer.The 4 μm resin spherical cores were synthesized by monodispersion polymerization method.Then they were contributed to electrical conductivity by electrolessly plating Ni-P layer and gold layer.These particles have good corrosion resistance,high stability,and enough mechanical strength.When mixed with thermosetting epoxy resin to produce anisotropic conductive adhesive(ACA),it can realize a good conductive bonding between bumps on dies and pads on substrates.This environmentally friendly conductive material offers numerous advantages over conventional solder technology and is an ideal substitute for the lead-contained solder in electronics packaging.
基金This work was funded by the financial support of the National Natural Science Foundation of China(Project No.20274018)Nankai University.
文摘Monodisperse crosslinked poly(chloromethylstyrene-co-divinylbenzene)(poly(CMSt-co-DVB))microsphereswere prepared by distillation-precipitation copolymerization of chloromethylstyrene(CMSt)and divinylbenzene(DVB)inneat acetonitrile.The polymer particles had clean surfaces due to the absence of any added stabilizer.The size of the particlesranges from 2.59 μm to 3.19 μm and with mono-dispersity around 1.002-1.014.The effects of monomer feed incopolymerization on the microsphere formation were described.The polymer microspheres were characterized by SEM andchlorinity elemental analysis.
文摘Monodisperse titania glycolate submicrospheres were synthesized by a modified sol-gel route, in which ultrasonic treatment was introduced to improve the reaction efficiency. The as-prepared products were characterized by means of Fourier transform infrared spectrum (FT-IR), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results indicate that the as-prepared products are titania glycolate submicrospheres with diameters of 230-330 nm. The average particle diameter is estimated to be about 280 nm. Ultrasonic treatment has an important influence on the morphology of the produced titania glycolates. After calcination at 450°C for 2 h, these titania glycolates were completely converted into anatase TiO2. The morphology of TiO2 particles was well reserved during the calcination process except for a reduction of 18% in the average particle size.
基金supported by the National Natural Science Foundation of China(No.30870679 and 30970787)National Basic Research Program of China(No.2006CB933206 and 2006CB705606)
基金National Natural Science Foundation of China(51873079)for financial support。
文摘Simultaneous achievement in high solid content and high microsphere yield is deemed a challenge in the fabrication of monodisperse microspheres by precipitation polymerization.We herein demonstrate that micro-sized monodisperse poly(methacrylic monomer-divinylbenzene)microspheres containing epoxy,lauyl,carboxyl and hydroxyl functions can be fabricated by solvothermal precipitation copolymerization at 20%(mass)monomer loading with over 94%microsphere yield.The morphology and porosity of the obtained particles can be readily tuned by cosolvent-acetonitrile binary solvents.Addition of a small amount of cosolvent that has similar solubility parameter to that of the functional monomer can significantly improve the monodispersity of the obtained microspheres.When tetrahydrofuran was used as the co-solvent,the surface area of the highly porous microspheres achieved higher than 400 m^(2)·g^(-1).Solvothermal precipitation co-polymerization can be expected in scale-up fabrication of various monodisperse functional microspheres free of any surfactant and additive.