Catalytic polymerization of acetylene in the presence of n5-C5H5-M-(CO)3 R (M=Mo,W;R=CH3-,C2H5-) has been studied.The results show that these complexes possess catalytic activities for the polymerization and copolymer...Catalytic polymerization of acetylene in the presence of n5-C5H5-M-(CO)3 R (M=Mo,W;R=CH3-,C2H5-) has been studied.The results show that these complexes possess catalytic activities for the polymerization and copolymerization of monosubstituted acetylene.The catalytic mechanism has been preliminarily discussed.It is suggested that the active species be metal-car-bene.In our previous publications we reported the synthesis of some new Fischer's molybdenum and tungsten-carbene complexes and catalytic activity for alkyne polymerization.The results show that the activity of Fischer's molybdenum-carbene is higher than that of tungsten.The catalytic polymerization of alkyne by M-σ-c bond-containing complexes of molybdenum and tungsten has not been reported yet in literature.Therefore,four M-σ-C bondontaining complexes of molybdenum and tungsten were synthesized by using the method reported in the literature,and catalyst polymerization of alkyne by these complexes was examined.展开更多
A novel multiplayer film was assembled from poly[(4 carboxyphenyl)acetylene](PCPA) and diazoresin(DR) in aqueous solution via electrostatic attraction. Under UV irradiation, following the decomposition of diazonium gr...A novel multiplayer film was assembled from poly[(4 carboxyphenyl)acetylene](PCPA) and diazoresin(DR) in aqueous solution via electrostatic attraction. Under UV irradiation, following the decomposition of diazonium group between the adjacent interfaces of the multiplayers, the ionic bonds of the self assembly film convert to covalent bonds and the film becomes very stable toward electrolyte solutions. Thus the photoelectric conversion property of poly[(4 carboxyphenyl)acetylene] containing film can be measured in conventional three electrode photoelectrochemical cell, and 0.5 mol/L KCl solution can be used as the supporting electrolyte. The photocurrent spectroscopy responses coincide with the absorption spectrum of the irradiated self assembly film, which indicates that the irradiated DR/PCPA film is responsible for the photocurrent generation.展开更多
Full conjugated multilayer thin films fabricated by the alternate adsor ption of partially doped polyaniline (PANI) as a polycation and water-soluble p o ly(4-carboxyphenyl)acetylene (PA) as a polyanion were used as n...Full conjugated multilayer thin films fabricated by the alternate adsor ption of partially doped polyaniline (PANI) as a polycation and water-soluble p o ly(4-carboxyphenyl)acetylene (PA) as a polyanion were used as nanoreactors to s t udy the in situ preparation of PbS nanoparticles.First,the self-assembled mu ltilayers were immersed in a 1 mol/L NaOH solution to fabricate a controlled con tent of free carboxylic acid binding groups.Chemical reaction within the polyme r film was initiated by absorbing Pb 2+ from a 0 4 mol/L aqueous solutio n of Pb(Ac) 2 and followed by exposing the film to H 2S gas.UV-Vis absorp tion studies re veal that the absorption spectral profiles of the films are dependent on the dip ping time of the film in the Pb(Ac) 2 solution.AFM and TEM microscopic examina tions o f the films reveal that PbS crystals with rhomboid structures are formed in the films.The particles of narrow size distribution stand vertically on the fil m plane.Due to being doped by PbS,the photoelectric conversion property of ultra-thin composite films,which can be measured with a conventional three-e lectrod e photoelectrochemical cell using 0 5 mol/L KCl solution as the supporting elec tr olyte,is improved obviously.The results show that the value of the photocurren t for an 8\|layer film is 3 times higher than that of the original film.展开更多
In this review we discuss the history of research into the use of gold for the acetylene hydrochlorin‐ation reaction, and describe the recent developments which have led to its commercialisation. We discuss the use o...In this review we discuss the history of research into the use of gold for the acetylene hydrochlorin‐ation reaction, and describe the recent developments which have led to its commercialisation. We discuss the use of different precursors and the addition to gold of a secondary metal as methods which attempt to improve these catalysts, and consider the nature of the active gold species. The vast majority of poly vinyl chloride （PVC） produced globally still uses a mercuric chloride as a cata‐lyst, despite the environmental problems associated with it. Due to the agreement by the Chinese government to remove mercury usage in the PVC industry over the course of the next few years there is an obvious need to find a replacement catalyst;the potential use of gold for this process has been well known for several decades and to date gold seems to be the best candidate for this, pri‐marily due to its superior selectivity when compared to other metals.展开更多
文摘Catalytic polymerization of acetylene in the presence of n5-C5H5-M-(CO)3 R (M=Mo,W;R=CH3-,C2H5-) has been studied.The results show that these complexes possess catalytic activities for the polymerization and copolymerization of monosubstituted acetylene.The catalytic mechanism has been preliminarily discussed.It is suggested that the active species be metal-car-bene.In our previous publications we reported the synthesis of some new Fischer's molybdenum and tungsten-carbene complexes and catalytic activity for alkyne polymerization.The results show that the activity of Fischer's molybdenum-carbene is higher than that of tungsten.The catalytic polymerization of alkyne by M-σ-c bond-containing complexes of molybdenum and tungsten has not been reported yet in literature.Therefore,four M-σ-C bondontaining complexes of molybdenum and tungsten were synthesized by using the method reported in the literature,and catalyst polymerization of alkyne by these complexes was examined.
文摘A novel multiplayer film was assembled from poly[(4 carboxyphenyl)acetylene](PCPA) and diazoresin(DR) in aqueous solution via electrostatic attraction. Under UV irradiation, following the decomposition of diazonium group between the adjacent interfaces of the multiplayers, the ionic bonds of the self assembly film convert to covalent bonds and the film becomes very stable toward electrolyte solutions. Thus the photoelectric conversion property of poly[(4 carboxyphenyl)acetylene] containing film can be measured in conventional three electrode photoelectrochemical cell, and 0.5 mol/L KCl solution can be used as the supporting electrolyte. The photocurrent spectroscopy responses coincide with the absorption spectrum of the irradiated self assembly film, which indicates that the irradiated DR/PCPA film is responsible for the photocurrent generation.
文摘Full conjugated multilayer thin films fabricated by the alternate adsor ption of partially doped polyaniline (PANI) as a polycation and water-soluble p o ly(4-carboxyphenyl)acetylene (PA) as a polyanion were used as nanoreactors to s t udy the in situ preparation of PbS nanoparticles.First,the self-assembled mu ltilayers were immersed in a 1 mol/L NaOH solution to fabricate a controlled con tent of free carboxylic acid binding groups.Chemical reaction within the polyme r film was initiated by absorbing Pb 2+ from a 0 4 mol/L aqueous solutio n of Pb(Ac) 2 and followed by exposing the film to H 2S gas.UV-Vis absorp tion studies re veal that the absorption spectral profiles of the films are dependent on the dip ping time of the film in the Pb(Ac) 2 solution.AFM and TEM microscopic examina tions o f the films reveal that PbS crystals with rhomboid structures are formed in the films.The particles of narrow size distribution stand vertically on the fil m plane.Due to being doped by PbS,the photoelectric conversion property of ultra-thin composite films,which can be measured with a conventional three-e lectrod e photoelectrochemical cell using 0 5 mol/L KCl solution as the supporting elec tr olyte,is improved obviously.The results show that the value of the photocurren t for an 8\|layer film is 3 times higher than that of the original film.
文摘In this review we discuss the history of research into the use of gold for the acetylene hydrochlorin‐ation reaction, and describe the recent developments which have led to its commercialisation. We discuss the use of different precursors and the addition to gold of a secondary metal as methods which attempt to improve these catalysts, and consider the nature of the active gold species. The vast majority of poly vinyl chloride （PVC） produced globally still uses a mercuric chloride as a cata‐lyst, despite the environmental problems associated with it. Due to the agreement by the Chinese government to remove mercury usage in the PVC industry over the course of the next few years there is an obvious need to find a replacement catalyst;the potential use of gold for this process has been well known for several decades and to date gold seems to be the best candidate for this, pri‐marily due to its superior selectivity when compared to other metals.
