Polyaniline(PAn)doped with multiple sulfonic acid system of dodecylbenzenesulfonic acid(DBSA)and sulfosalicylic acid(SSA)was synthesized by emulsion polymerization using ammonium persulfate(APS)as an oxidizing agent i...Polyaniline(PAn)doped with multiple sulfonic acid system of dodecylbenzenesulfonic acid(DBSA)and sulfosalicylic acid(SSA)was synthesized by emulsion polymerization using ammonium persulfate(APS)as an oxidizing agent in the presence and the absence of a constant magnetic field(MF)of 0.8 T.The structure and properties of the PAn were characterized by X-ray diffractometer(XRD),thermogravimetric apparatus(TGA),FT-IR spectroscope(FT-IR)and four probe digital multimeter.The results indicate that,when the molar ratio of DBSA to SSA is 1/3,that of dopant to An is 3/2,that of APS to An is 4/5 in the synthesizing media,and the doping time is 3 h,the conductivity of the PAn synthesized in the presence of the MF of 0.8 T reaches 5.88 S/cm,which is higher than that of the PAn synthesized in the absence of the MF.The thermal stability,the crystallinity and the doping degree of the PAn synthesized in the presence of the MF are also improved.MF not only enhances the conductivity,but also reduces the doping time,the dosage of the dopant and the oxidizing agent when the conductivity reaches the maximum.展开更多
The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to ...The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to shorter wavelength when polyaniline was doped with CSAH in N methyl 2 pyrrolidione (NMP) solvent, while the red shift of polaron band was observed when it was in N, N dimethylformamide (DMF). It indicates that the influence of different processing solvents on the doping property of polyaniline is greatly different. N methyl 2 pyrrolidione is a good solvent for polyaniline, polyaniline chain is unfolded in it. The interaction of NMP with CSAH is so strong that the resulting product is apt to dedoping, while the solubility of polyaniline in DMF is relatively low and polyaniline chain is in partly folded state. Thus the doping reaction is kinetically disadvantageous but thermodynamically advantageous.展开更多
The DBSA-PANI-Fe composite powder with 50wt% of Fe nanoparticles was prepared by mechanically mixing the DBSA-doped polyaniline powder and Fe nanoparticles. The composite powder was compacted to pellets and the pellet...The DBSA-PANI-Fe composite powder with 50wt% of Fe nanoparticles was prepared by mechanically mixing the DBSA-doped polyaniline powder and Fe nanoparticles. The composite powder was compacted to pellets and the pellets were annealed in vacuum at 443,493,543, and 593 K for 60 and 120 min. The conductivity of the pellet increases markedly with increasing the annealing temperature up to 493 K, and then decreases with further increasing the annealing temperature. When the pellet was annealed at 493 K for 60 min, the increment of conductivity reaches a maximum value, and the conductivity is 2.6 times as large as that of the pellet unannealed. The conductivities of the pellets annealed under the conditions of 543 K/120 min, 593 K/60 min, and 593 K/120 min are lower than the conductivity of the pellet unannealed. For all the pellets, the variation in conductivity with temperature reveals that the charge transport mechanism can be considered to be 1-D variable-range-hopping （1-D VRH）. The composite pellet shows a magnetic hysteresis loop independent of the annealing condition. The saturation magnetization is about 5.4×10^4 emu/kg. The saturation field and the coercivity are estimated to be 4.38×10^5 and 3.06×10^4 A/m, respectively. The crystalline structure ofFe nanoparticles in the composites does not change with the annealing condition. The annealing condition cannot destroy the polymer backbones.展开更多
4-(3-(4-((4-Nitrophenyl)azo)phenyloxy)propyl)aminobenzene sulfonic acid (C3-ABSA) was synthesized by the reaction of 3-bromide-1-(4-((4-nitrophenyl)azo)phenyloxy)propane (B3) with sodium p-aminobenzene sulfonic acid (...4-(3-(4-((4-Nitrophenyl)azo)phenyloxy)propyl)aminobenzene sulfonic acid (C3-ABSA) was synthesized by the reaction of 3-bromide-1-(4-((4-nitrophenyl)azo)phenyloxy)propane (B3) with sodium p-aminobenzene sulfonic acid (ABSA) and acidification with hydrochloric acid. The C3-ABSA was characterized by FTIR, H-1-NMR and second ion mass spectrum (SIMS). The molecular formula of dehydrated C3-ABSA was estimated to be ca. C21H20O6N4S by SIMS. Its decomposition temperature was measured by TGA to be ca. 232 degreesC. It was found that tubular polyaniline (PANI) with a conductivity of 1.1 S/cm at room temperature was successfully synthesized by in-situ doping polymerization in the presence of C3-ABSA as a dopant.展开更多
Ag nanoparticles were sputter-deposited on ammonium persulfate((NH_4)_2S_2O_8) powder to obtain(NH_4)_2S_2O_8-Ag powder, which was used to synthesize the HCl-doped polyaniline-Ag(HCl-PANI-Ag) composite via a polymeriz...Ag nanoparticles were sputter-deposited on ammonium persulfate((NH_4)_2S_2O_8) powder to obtain(NH_4)_2S_2O_8-Ag powder, which was used to synthesize the HCl-doped polyaniline-Ag(HCl-PANI-Ag) composite via a polymerization procedure. The Ag nanoparticles were dispersed in the HCl-PANI matrix, and their sizes mainly ranged from 3 to 6 nm. The Ag nanoparticles did not affect the structure of emeraldine salt in the composite, and they increased the ordered crystalline regions in the HCl-PANI matrix. The HCl-PANI-Ag composite had a conductivity of(6.8 ± 0.1) S/cm, which is about four times larger than that of the HCl-PANI. The charge transport mechanism in the composite is explained by the three-dimensional Mott variable-range hopping(3D-Mott-VRH).展开更多
The chain structure of polyaniline doped with HCl or CF_3COOH has been investigated by FTIR, solid state ^(13)CNMR, resonance laser Raman and UV-VIS spectroscopies. The results show that during the protonic acid dopin...The chain structure of polyaniline doped with HCl or CF_3COOH has been investigated by FTIR, solid state ^(13)CNMR, resonance laser Raman and UV-VIS spectroscopies. The results show that during the protonic acid doping, a partial redox reaction takes place between the quinone-diimine and benzene-diamine units and it leads to a long conjugate system with a certain charge distribution.展开更多
基金Project(20176066)supported by the National Natural Science Foundation of China
文摘Polyaniline(PAn)doped with multiple sulfonic acid system of dodecylbenzenesulfonic acid(DBSA)and sulfosalicylic acid(SSA)was synthesized by emulsion polymerization using ammonium persulfate(APS)as an oxidizing agent in the presence and the absence of a constant magnetic field(MF)of 0.8 T.The structure and properties of the PAn were characterized by X-ray diffractometer(XRD),thermogravimetric apparatus(TGA),FT-IR spectroscope(FT-IR)and four probe digital multimeter.The results indicate that,when the molar ratio of DBSA to SSA is 1/3,that of dopant to An is 3/2,that of APS to An is 4/5 in the synthesizing media,and the doping time is 3 h,the conductivity of the PAn synthesized in the presence of the MF of 0.8 T reaches 5.88 S/cm,which is higher than that of the PAn synthesized in the absence of the MF.The thermal stability,the crystallinity and the doping degree of the PAn synthesized in the presence of the MF are also improved.MF not only enhances the conductivity,but also reduces the doping time,the dosage of the dopant and the oxidizing agent when the conductivity reaches the maximum.
文摘The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to shorter wavelength when polyaniline was doped with CSAH in N methyl 2 pyrrolidione (NMP) solvent, while the red shift of polaron band was observed when it was in N, N dimethylformamide (DMF). It indicates that the influence of different processing solvents on the doping property of polyaniline is greatly different. N methyl 2 pyrrolidione is a good solvent for polyaniline, polyaniline chain is unfolded in it. The interaction of NMP with CSAH is so strong that the resulting product is apt to dedoping, while the solubility of polyaniline in DMF is relatively low and polyaniline chain is in partly folded state. Thus the doping reaction is kinetically disadvantageous but thermodynamically advantageous.
基金the Education Reform Foundation of University of Science and Technology Beijing (No.00008099)
文摘The DBSA-PANI-Fe composite powder with 50wt% of Fe nanoparticles was prepared by mechanically mixing the DBSA-doped polyaniline powder and Fe nanoparticles. The composite powder was compacted to pellets and the pellets were annealed in vacuum at 443,493,543, and 593 K for 60 and 120 min. The conductivity of the pellet increases markedly with increasing the annealing temperature up to 493 K, and then decreases with further increasing the annealing temperature. When the pellet was annealed at 493 K for 60 min, the increment of conductivity reaches a maximum value, and the conductivity is 2.6 times as large as that of the pellet unannealed. The conductivities of the pellets annealed under the conditions of 543 K/120 min, 593 K/60 min, and 593 K/120 min are lower than the conductivity of the pellet unannealed. For all the pellets, the variation in conductivity with temperature reveals that the charge transport mechanism can be considered to be 1-D variable-range-hopping （1-D VRH）. The composite pellet shows a magnetic hysteresis loop independent of the annealing condition. The saturation magnetization is about 5.4×10^4 emu/kg. The saturation field and the coercivity are estimated to be 4.38×10^5 and 3.06×10^4 A/m, respectively. The crystalline structure ofFe nanoparticles in the composites does not change with the annealing condition. The annealing condition cannot destroy the polymer backbones.
文摘4-(3-(4-((4-Nitrophenyl)azo)phenyloxy)propyl)aminobenzene sulfonic acid (C3-ABSA) was synthesized by the reaction of 3-bromide-1-(4-((4-nitrophenyl)azo)phenyloxy)propane (B3) with sodium p-aminobenzene sulfonic acid (ABSA) and acidification with hydrochloric acid. The C3-ABSA was characterized by FTIR, H-1-NMR and second ion mass spectrum (SIMS). The molecular formula of dehydrated C3-ABSA was estimated to be ca. C21H20O6N4S by SIMS. Its decomposition temperature was measured by TGA to be ca. 232 degreesC. It was found that tubular polyaniline (PANI) with a conductivity of 1.1 S/cm at room temperature was successfully synthesized by in-situ doping polymerization in the presence of C3-ABSA as a dopant.
基金financially supported by the Fundamental Research Funds for the Central Universities of China (No. 8220)
文摘Ag nanoparticles were sputter-deposited on ammonium persulfate((NH_4)_2S_2O_8) powder to obtain(NH_4)_2S_2O_8-Ag powder, which was used to synthesize the HCl-doped polyaniline-Ag(HCl-PANI-Ag) composite via a polymerization procedure. The Ag nanoparticles were dispersed in the HCl-PANI matrix, and their sizes mainly ranged from 3 to 6 nm. The Ag nanoparticles did not affect the structure of emeraldine salt in the composite, and they increased the ordered crystalline regions in the HCl-PANI matrix. The HCl-PANI-Ag composite had a conductivity of(6.8 ± 0.1) S/cm, which is about four times larger than that of the HCl-PANI. The charge transport mechanism in the composite is explained by the three-dimensional Mott variable-range hopping(3D-Mott-VRH).
基金Project supported by the National Natural Science Foundation of China.
文摘The chain structure of polyaniline doped with HCl or CF_3COOH has been investigated by FTIR, solid state ^(13)CNMR, resonance laser Raman and UV-VIS spectroscopies. The results show that during the protonic acid doping, a partial redox reaction takes place between the quinone-diimine and benzene-diamine units and it leads to a long conjugate system with a certain charge distribution.
