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1986 Volume 3 Issue 6
1986, 3(6): 1-8
Abstract:
A review on progress of the polymer film modified electrode with 24 references is presented. The characters, types electrode process and the applications of the polymer film electrode are discussed.
A review on progress of the polymer film modified electrode with 24 references is presented. The characters, types electrode process and the applications of the polymer film electrode are discussed.
1986, 3(6): 9-14
Abstract:
The thermal decomposition processes and hydrogenation reactions of K2Co[Fe(CN)6]·H2O and Co3[Fe(CN)6]·7H2O in hydrogen were studied by GC to discern the gas products and by Mossbauer spectroscopy, IR and XRD to determine the structure of the solid products. Their decomposition processes may be divided into three steps: (1) dehydration, (2) reduction of Fe (Ⅲ) to Fe(Ⅱ), and (3) rupture ofthe triple bond of C≡N- by hydrogenation to evolev NH3 and CH4. Iron-Cobalt alloy was formed at the final step of decomposition. K2Co[Fe(CN)6)·H2O and Co3[Fe(CN)6]·7H2O may be considered as a multibond activation model of bimetal coordination, since CN- acts as a typical ambident ligand in it. The activation of CN- triple bond has been discussed in terms of hydrogenation reaction.
The thermal decomposition processes and hydrogenation reactions of K2Co[Fe(CN)6]·H2O and Co3[Fe(CN)6]·7H2O in hydrogen were studied by GC to discern the gas products and by Mossbauer spectroscopy, IR and XRD to determine the structure of the solid products. Their decomposition processes may be divided into three steps: (1) dehydration, (2) reduction of Fe (Ⅲ) to Fe(Ⅱ), and (3) rupture ofthe triple bond of C≡N- by hydrogenation to evolev NH3 and CH4. Iron-Cobalt alloy was formed at the final step of decomposition. K2Co[Fe(CN)6)·H2O and Co3[Fe(CN)6]·7H2O may be considered as a multibond activation model of bimetal coordination, since CN- acts as a typical ambident ligand in it. The activation of CN- triple bond has been discussed in terms of hydrogenation reaction.
1986, 3(6): 15-19
Abstract:
A number of polyurethane based on liquid,chloroprene-hydroxyethyl methacrylate copolymer (CP-HEMA)-polystyrene (ST) interpenetrating polymer networks (PU-ST-IPN) were synthesized. Some physical properties were examined and density behavior was investigated.For 60% polyurethane (PU) system, the tensile strength and density were found to be increased clearly. Transmission electron micrographs showed the existence of phase separation and the sizes of ST domains dispersed in PU phase were esfimated about 500-4000Å. In comparison with correlative PU-MMA-IPN system, the IPN prepared had a more extensive phase separation and boundaries because of the higher compatibility in the PU-MMA-IPN.No phase inversion has been observed till up to 60% content of PU in system at which ST phase remained as a dispersed phase and PU as a continuous phase.It was considered as a result of the greater rate of PU formation than that of polymerization of ST. The relatively uniform distribution of domain size and the density effect indicated that the interentanglements between the two networks existed in the system, to some extent, would cause the incompatible system to become a partially compatible one.
A number of polyurethane based on liquid,chloroprene-hydroxyethyl methacrylate copolymer (CP-HEMA)-polystyrene (ST) interpenetrating polymer networks (PU-ST-IPN) were synthesized. Some physical properties were examined and density behavior was investigated.For 60% polyurethane (PU) system, the tensile strength and density were found to be increased clearly. Transmission electron micrographs showed the existence of phase separation and the sizes of ST domains dispersed in PU phase were esfimated about 500-4000Å. In comparison with correlative PU-MMA-IPN system, the IPN prepared had a more extensive phase separation and boundaries because of the higher compatibility in the PU-MMA-IPN.No phase inversion has been observed till up to 60% content of PU in system at which ST phase remained as a dispersed phase and PU as a continuous phase.It was considered as a result of the greater rate of PU formation than that of polymerization of ST. The relatively uniform distribution of domain size and the density effect indicated that the interentanglements between the two networks existed in the system, to some extent, would cause the incompatible system to become a partially compatible one.
1986, 3(6): 20-24
Abstract:
Several studies on the micro-and crystalline structure of solution-and suspension-chlorinated polyethylene(CPE) have appeared in literature.This paper presents our study on the structure of solid phase chlorinated powder polyethylene by means of 13C-nuclear magnetic resonance, infrared spectroscopy, pyrolysis-gas chromatography and differential scanning calorimetry.The results show that chlorination of the samples with low chlorine-content was hindered-type substitution,while that of the samples with chlorine content over 50 wt% seemed to be more complicated. The molecular chains of these CPE mainly composed of -CH2- and -CHCl- groups; only in the samples with chlorine-content over 50 wt% appeared -CCl2- groups, the quantity of which,however,was extremely small. The change of crystallization behavior of these CPE was different from both the solution-chlorinated and the suspension chlorinated polyethylenes.
Several studies on the micro-and crystalline structure of solution-and suspension-chlorinated polyethylene(CPE) have appeared in literature.This paper presents our study on the structure of solid phase chlorinated powder polyethylene by means of 13C-nuclear magnetic resonance, infrared spectroscopy, pyrolysis-gas chromatography and differential scanning calorimetry.The results show that chlorination of the samples with low chlorine-content was hindered-type substitution,while that of the samples with chlorine content over 50 wt% seemed to be more complicated. The molecular chains of these CPE mainly composed of -CH2- and -CHCl- groups; only in the samples with chlorine-content over 50 wt% appeared -CCl2- groups, the quantity of which,however,was extremely small. The change of crystallization behavior of these CPE was different from both the solution-chlorinated and the suspension chlorinated polyethylenes.
1986, 3(6): 25-29
Abstract:
The dynamic mechanical properties in terms of the storage modulus E', loss modulus E", and the loss tangentδ of poly (butadiene-co-acrylonitrile) with 40% acrylonitrile composites filled with graphite powder and molybdenum disulfide powder fillers have been studied. The effect of the volume fraction of fillers and the polymer-filler interaction on the above meationed parameters and relaxation spectra have been elucidated. A model has been tested for calculating the complex modulus E1* of interphase.
The dynamic mechanical properties in terms of the storage modulus E', loss modulus E", and the loss tangentδ of poly (butadiene-co-acrylonitrile) with 40% acrylonitrile composites filled with graphite powder and molybdenum disulfide powder fillers have been studied. The effect of the volume fraction of fillers and the polymer-filler interaction on the above meationed parameters and relaxation spectra have been elucidated. A model has been tested for calculating the complex modulus E1* of interphase.
1986, 3(6): 30-35
Abstract:
The physicochemical properties of Bi-P catalyst system and the mechanism of oxidation-dehydrodimerization and aromatization of propylene were investigated by using XPS,PAS, TPR and X-ray diffraction methods.The results indicated that propylene is dissociatively adsorbed on the surface of the catalyst and the activation of α-hydrogen is related to the strength of metal-oxygen bond in the catalyst. The products of allyl oxidation depend on the electron transference between the allylic intermediates and the catalyst.
The physicochemical properties of Bi-P catalyst system and the mechanism of oxidation-dehydrodimerization and aromatization of propylene were investigated by using XPS,PAS, TPR and X-ray diffraction methods.The results indicated that propylene is dissociatively adsorbed on the surface of the catalyst and the activation of α-hydrogen is related to the strength of metal-oxygen bond in the catalyst. The products of allyl oxidation depend on the electron transference between the allylic intermediates and the catalyst.
1986, 3(6): 36-39
Abstract:
The extraction behaviors of iron (Ⅲ) with N,N-di(1-methylheptyl) acetamide (N503) in hydrochlorie acid medium, including equilibrium time, the effect of additive agents and acidity, and extraction capacity have been described. The equation ofextraction reaction has been deduced through a study on the equilibrium as Fe3++H++4Cl-+3S (O)???19860611???HFeCl4·3S(O), where S refers to the extractant. The extrraction constant, Kex has been estimated as 10(2.19±0.04) (25℃, μ=4M). By means of both elemental analyses and thermal analysis, the composition of the coordination compound of iron(Ⅲ)obtained by saturation extraction has been identified as HFeCl4·2S. The species of coordination compound investigated by magnetic moment.UV and IR spectra measurements can be expressed as(H+·2S)(FeCl4-).
The extraction behaviors of iron (Ⅲ) with N,N-di(1-methylheptyl) acetamide (N503) in hydrochlorie acid medium, including equilibrium time, the effect of additive agents and acidity, and extraction capacity have been described. The equation ofextraction reaction has been deduced through a study on the equilibrium as Fe3++H++4Cl-+3S (O)???19860611???HFeCl4·3S(O), where S refers to the extractant. The extrraction constant, Kex has been estimated as 10(2.19±0.04) (25℃, μ=4M). By means of both elemental analyses and thermal analysis, the composition of the coordination compound of iron(Ⅲ)obtained by saturation extraction has been identified as HFeCl4·2S. The species of coordination compound investigated by magnetic moment.UV and IR spectra measurements can be expressed as(H+·2S)(FeCl4-).
1986, 3(6): 40-43
Abstract:
Methyl tributyltin maleate was copolymerizied with methyl, ethyl and butyl acrylates alternatively.Various copolymerization conditions such as amount and kind of initiators,concentration of monomers and solvents were examined. Copolymers were characterized by IR, 1H-NMR, elemental and TG analysis. The copolymers obtained are soluble in common organic solvents. Copolymer of MTBTM-MA is a transparant elastomer,while copolymers of MTBTM-EA and MTBTM-BA are viscous.
Methyl tributyltin maleate was copolymerizied with methyl, ethyl and butyl acrylates alternatively.Various copolymerization conditions such as amount and kind of initiators,concentration of monomers and solvents were examined. Copolymers were characterized by IR, 1H-NMR, elemental and TG analysis. The copolymers obtained are soluble in common organic solvents. Copolymer of MTBTM-MA is a transparant elastomer,while copolymers of MTBTM-EA and MTBTM-BA are viscous.
1986, 3(6): 44-47
Abstract:
The crystal of the title compound is triclinic with space group PI and a=11.949(6)Å, b=12.886(5)Å, c=11.557(6)Å, α=112.93(3)°, β=115.92(4)°, γ=82.41(4)°. Diffraction bata of 3739 independent reflections were collected on Nicolet XRD R3 four circle diffractometer using Mokα radiation. The crystal structure was solved by the heavy atom method and difference Fourier synthesis and refined by the block least square to a final R=0.113 based on 3019 unique reflections upon F0≥3σ(F0). the structure analysis showed that the coordination of neodymium by oxygen atoms is eightfold with a geometry of a slightly distorted square antiprism and average Nd-O bond length 2.453Å and O-Nd-O angle ranged from 69.3°to 147.4°
The crystal of the title compound is triclinic with space group PI and a=11.949(6)Å, b=12.886(5)Å, c=11.557(6)Å, α=112.93(3)°, β=115.92(4)°, γ=82.41(4)°. Diffraction bata of 3739 independent reflections were collected on Nicolet XRD R3 four circle diffractometer using Mokα radiation. The crystal structure was solved by the heavy atom method and difference Fourier synthesis and refined by the block least square to a final R=0.113 based on 3019 unique reflections upon F0≥3σ(F0). the structure analysis showed that the coordination of neodymium by oxygen atoms is eightfold with a geometry of a slightly distorted square antiprism and average Nd-O bond length 2.453Å and O-Nd-O angle ranged from 69.3°to 147.4°
1986, 3(6): 48-53
Abstract:
A formula for calculating M in a given interval of Wesslau distribution and Lansing-Kraemer distribution has been derived. It is impossible that the molecular weight of any polymer will distribute over the whole range of 0-∞, hencc a GPC curve always has two boundaries. Therefore a GPC curve should be treated as a normal distribution curve wih its side tails cut out. This paper has shown that three parameters (M0, β and UR) are necessary for characterizing a normal GPC curve.The precision of M calculated from GPC curve by Wesslau function is discussed.
A formula for calculating M in a given interval of Wesslau distribution and Lansing-Kraemer distribution has been derived. It is impossible that the molecular weight of any polymer will distribute over the whole range of 0-∞, hencc a GPC curve always has two boundaries. Therefore a GPC curve should be treated as a normal distribution curve wih its side tails cut out. This paper has shown that three parameters (M0, β and UR) are necessary for characterizing a normal GPC curve.The precision of M calculated from GPC curve by Wesslau function is discussed.
1986, 3(6): 54-57
Abstract:
The effects of normal aliphatic alcohols (C1-C6, and C8) on the demulsifibility of feur demulsifiers(block type polyoxyethylene-polyoxypropylene copolymer) for W/O type emulsion have been studied.The results show that the addition of alcohols (>1%)greatly enhances the demulsification and n-amyl alcohol is found to be the most effective.
The effects of normal aliphatic alcohols (C1-C6, and C8) on the demulsifibility of feur demulsifiers(block type polyoxyethylene-polyoxypropylene copolymer) for W/O type emulsion have been studied.The results show that the addition of alcohols (>1%)greatly enhances the demulsification and n-amyl alcohol is found to be the most effective.
1986, 3(6): 58-60
Abstract:
By reacting of benzene with Chlorine in the Presence of Sb2S3-I2 as a Catalyst,We have Obtained paradichlorobenzene under mild conditions in high yields and goodquality. The experiments indicate that the used catalyst has fair activities on the reactionof selective catalytic chlorination of benzene. In the fraction of dichlorobenzene theproportion of paradichlorobenzene is equal to 88% or so. The main factors which affect the reaction are reaction temperature, the chlorine-flow speed, the amount of the catalyst used and stirring efficiency. Experiments showthat the optimum reaction conditions are:(1) the molar ratio of chlorine to benzene:2.8:1, (2) chlorination temperature: 20~60℃, and (3) amounts of Sb2S3 and I2: 1%and 0.2% of benzene weight, respectively.
By reacting of benzene with Chlorine in the Presence of Sb2S3-I2 as a Catalyst,We have Obtained paradichlorobenzene under mild conditions in high yields and goodquality. The experiments indicate that the used catalyst has fair activities on the reactionof selective catalytic chlorination of benzene. In the fraction of dichlorobenzene theproportion of paradichlorobenzene is equal to 88% or so. The main factors which affect the reaction are reaction temperature, the chlorine-flow speed, the amount of the catalyst used and stirring efficiency. Experiments showthat the optimum reaction conditions are:(1) the molar ratio of chlorine to benzene:2.8:1, (2) chlorination temperature: 20~60℃, and (3) amounts of Sb2S3 and I2: 1%and 0.2% of benzene weight, respectively.
1986, 3(6): 61-63
Abstract:
(±)-2-(6-Methoxyl-2-naphthyl)-propionic aldehyde has been oxidized to the corre-sponding acid with hydrogen peroxide by use of selenium dioxide as catalyst insteadof Tollen's reagent. The optimum conditions obtained are reported in this paper:catalyst/aldehyde=0. 01(wt), aldehyde/absolute ethyl alcohol=0.20(wt/vol), watercontent in the reaction medium 3%, H2O2/aldehyde=1-1.2(mol), reaction tempera-ture and time: 10-15℃ for 5 days. The yield of acid was 73.13%. less than that bysilver nitrate method. Content of Se in the product≤3ppm.
(±)-2-(6-Methoxyl-2-naphthyl)-propionic aldehyde has been oxidized to the corre-sponding acid with hydrogen peroxide by use of selenium dioxide as catalyst insteadof Tollen's reagent. The optimum conditions obtained are reported in this paper:catalyst/aldehyde=0. 01(wt), aldehyde/absolute ethyl alcohol=0.20(wt/vol), watercontent in the reaction medium 3%, H2O2/aldehyde=1-1.2(mol), reaction tempera-ture and time: 10-15℃ for 5 days. The yield of acid was 73.13%. less than that bysilver nitrate method. Content of Se in the product≤3ppm.
1986, 3(6): 64-67
Abstract:
The morphology of melt-drawn films of copolymers of vinylidene fluoride and te-trafluoroethylene with various compositions has been investigated by TEM, IR,WAXDand DSC techniques. The melt-drawn films contain highly oriented lamellae consisted of β crystal formwithin the composition range investigated (tetrafluoroethylene content of 10-40mol%)The β phase is stable at higher temperatures. No phase transition has been observedduring the uniaxial deformation process of the films.
The morphology of melt-drawn films of copolymers of vinylidene fluoride and te-trafluoroethylene with various compositions has been investigated by TEM, IR,WAXDand DSC techniques. The melt-drawn films contain highly oriented lamellae consisted of β crystal formwithin the composition range investigated (tetrafluoroethylene content of 10-40mol%)The β phase is stable at higher temperatures. No phase transition has been observedduring the uniaxial deformation process of the films.
1986, 3(6): 68-69
Abstract:
The proton dissociation process of tris- (hydroxymethyl) -aminomethane(THAM)has been studied by 1H and 13C NMR methods.The proton dissociation constant of thetitle compound determined was pK=8,15, which was in good agreement with the re-sults obtained by other methods in the literature.
The proton dissociation process of tris- (hydroxymethyl) -aminomethane(THAM)has been studied by 1H and 13C NMR methods.The proton dissociation constant of thetitle compound determined was pK=8,15, which was in good agreement with the re-sults obtained by other methods in the literature.
1986, 3(6): 70-72
Abstract:
The influence of electrolytes on the stability of anionic dimethylpolysiloxanelatex has been investigated. It was found that the stability of these latices towardselectrolytes was greatly improved by incorporation with alkyl polyoxyethylene glycolmonoethers. However, excess anionic surfactants would appreciably impair the stabilityof these latices towards electrolytes and, in this case, a much more amount of alkylpolyoxyethylene glycol monoethers is needed to prevent these latices from coagulationin the presence of electrolytes.
The influence of electrolytes on the stability of anionic dimethylpolysiloxanelatex has been investigated. It was found that the stability of these latices towardselectrolytes was greatly improved by incorporation with alkyl polyoxyethylene glycolmonoethers. However, excess anionic surfactants would appreciably impair the stabilityof these latices towards electrolytes and, in this case, a much more amount of alkylpolyoxyethylene glycol monoethers is needed to prevent these latices from coagulationin the presence of electrolytes.
1986, 3(6): 73-75
Abstract:
The fluorescent solid complex of europium nitrate with 1, 8-naphthyridine-N-oxide(napyo) has been synthesized.The new complex has the composition Eu(napyo)2 (NO3)3characterized by elemental analyses, infrared spectra, ultraviolet spectra, fluorescencespectra, molar conductance and x-ray powder diffraction measurements.
The fluorescent solid complex of europium nitrate with 1, 8-naphthyridine-N-oxide(napyo) has been synthesized.The new complex has the composition Eu(napyo)2 (NO3)3characterized by elemental analyses, infrared spectra, ultraviolet spectra, fluorescencespectra, molar conductance and x-ray powder diffraction measurements.
1986, 3(6): 76-79
Abstract:
The dependence of the intrinsic viscosities of polyacrylamide(PAM)and hydrolyzedpolyacrylamide(HPAM) in water on the concentration of added salt (sodium nitrate)and time was studied.The intrinsic viscosities of HPAM decrease with the increase ofthe concentration of added salt.When the salt concentration is high,the ratio[η)/M isinversely proportional to the concentration of salt added to the polyelectrolytes. The Solution instability of PAM and HPAM was examined in 1M NaNO3 aqueoussolution for samples with different molecular weight and hydrolyzed degree. The solu-tion viscosities decrease with time. After a certain period of storage the ratio ((ηsp/C)t0 - (ηsp/C)ti)/(ηsp/C)t0 is found to be proportional to the logarithm of Mw. Mw stands for the apprent molecular weight of HPAM.
The dependence of the intrinsic viscosities of polyacrylamide(PAM)and hydrolyzedpolyacrylamide(HPAM) in water on the concentration of added salt (sodium nitrate)and time was studied.The intrinsic viscosities of HPAM decrease with the increase ofthe concentration of added salt.When the salt concentration is high,the ratio[η)/M isinversely proportional to the concentration of salt added to the polyelectrolytes. The Solution instability of PAM and HPAM was examined in 1M NaNO3 aqueoussolution for samples with different molecular weight and hydrolyzed degree. The solu-tion viscosities decrease with time. After a certain period of storage the ratio ((ηsp/C)t0 - (ηsp/C)ti)/(ηsp/C)t0 is found to be proportional to the logarithm of Mw. Mw stands for the apprent molecular weight of HPAM.
