Login In
2001 Volume 18 Issue 8
2001, 18(8): 596-598
Abstract:
An elastomeric stamp with micro-patterns on the surface was molded out of poly(dimethylsiloxane). Then the micro contact printing was carried out on the glass substrate with octadecyltrichlorosilane(OTS), which produced hydrophobic-micro patterns on hydrophilic substrate. After the substrate was drawn out from salt solution, the solution drops could stay in the hydrophilic microzone to give regular CdCl2, Zn(NO3)2 and Pb(NO3)2 micro crystal arrays. The latter compounds were then converted to sulfide arrays by reacting with H2S. The PbS micropatterns with printed substrate can also be produced by the same proceduce via solution deposition method.
An elastomeric stamp with micro-patterns on the surface was molded out of poly(dimethylsiloxane). Then the micro contact printing was carried out on the glass substrate with octadecyltrichlorosilane(OTS), which produced hydrophobic-micro patterns on hydrophilic substrate. After the substrate was drawn out from salt solution, the solution drops could stay in the hydrophilic microzone to give regular CdCl2, Zn(NO3)2 and Pb(NO3)2 micro crystal arrays. The latter compounds were then converted to sulfide arrays by reacting with H2S. The PbS micropatterns with printed substrate can also be produced by the same proceduce via solution deposition method.
2001, 18(8): 599-601
Abstract:
Several new hydrazides of 1-aryl-1,4-dihydro-6-methyl-4-pyridazinone have been synthesized and are characterized by 1H NMR and elemental analysis. The preliminary biological test showed that compounds(3a,3h) possess higher antiviral activities against rice stripe virus and 3a,3g shows higher bioactivity against tobacco mosaic virus(TMV).
Several new hydrazides of 1-aryl-1,4-dihydro-6-methyl-4-pyridazinone have been synthesized and are characterized by 1H NMR and elemental analysis. The preliminary biological test showed that compounds(3a,3h) possess higher antiviral activities against rice stripe virus and 3a,3g shows higher bioactivity against tobacco mosaic virus(TMV).
2001, 18(8): 602-605
Abstract:
Study on the effects of penicillin-K on the partial phasediagram of CTAB/n-C5H11OH/H2O system showed that penicillin-K can increase the amount ofn-C5H11OH solubilized in O/W microemulsion as well as the amount of water in W/O microemulsion. Penicillin-K was found to be solubilized easier than vitamin C as previously reported by authors. It appears that the presence of penicillin-K is probably responsible for stabilization of O/W and W/O microemulsion and at the same time for reduction of the stability of the lamellar liquid crystal phase, resulting in the transition of the latter to bicontineuous structure.
Study on the effects of penicillin-K on the partial phasediagram of CTAB/n-C5H11OH/H2O system showed that penicillin-K can increase the amount ofn-C5H11OH solubilized in O/W microemulsion as well as the amount of water in W/O microemulsion. Penicillin-K was found to be solubilized easier than vitamin C as previously reported by authors. It appears that the presence of penicillin-K is probably responsible for stabilization of O/W and W/O microemulsion and at the same time for reduction of the stability of the lamellar liquid crystal phase, resulting in the transition of the latter to bicontineuous structure.
2001, 18(8): 606-609
Abstract:
The photocurable carboxylated epoxy acrylate(CEA) resins were synthesized via the reaction between hydroxyl group on epoxy acrylate resin(EA) and polybasic carboxylic acid anhydride, e.g. maleic anhydride(MAn), phthalic anhydride(PAn), succinic anhydride (SAn), tetrahydrophthalic anhydride(THPAn) and hexahydrophthalic anhydride(HHPAn). The catalyst, such as tetramethyl ammonium bromide, could effectively accelerate the reaction. If one-third of epoxy resin based on CEA was cooperated with CEA resin, the dried films comprised of MAn or PAn modified resin were completely unsoluble in alkaline solution before photocuring, but not for that comprised of SAn, TPAn or HPAn resins. The formulations mixtures containing THPAn or HHPAn resins could be photopolymerized rapidly to a greater extent compared with that containing MAn or PAn resins. The photocured and post-thermal-cured films exhibited satisfactory thermal stability except for that containing PAn resin. THPAn and HHPAn were the appropriate carboxylic anhydride for the preparation of the alkaline developable photosensitive solder resist.
The photocurable carboxylated epoxy acrylate(CEA) resins were synthesized via the reaction between hydroxyl group on epoxy acrylate resin(EA) and polybasic carboxylic acid anhydride, e.g. maleic anhydride(MAn), phthalic anhydride(PAn), succinic anhydride (SAn), tetrahydrophthalic anhydride(THPAn) and hexahydrophthalic anhydride(HHPAn). The catalyst, such as tetramethyl ammonium bromide, could effectively accelerate the reaction. If one-third of epoxy resin based on CEA was cooperated with CEA resin, the dried films comprised of MAn or PAn modified resin were completely unsoluble in alkaline solution before photocuring, but not for that comprised of SAn, TPAn or HPAn resins. The formulations mixtures containing THPAn or HHPAn resins could be photopolymerized rapidly to a greater extent compared with that containing MAn or PAn resins. The photocured and post-thermal-cured films exhibited satisfactory thermal stability except for that containing PAn resin. THPAn and HHPAn were the appropriate carboxylic anhydride for the preparation of the alkaline developable photosensitive solder resist.
2001, 18(8): 610-613
Abstract:
Two series of polymers based on zinc complexes of the tetrathiafulvalene tetrathiolate(ttftt4-) of stoichiometry[(Zn-ttftt)Mx]n (M=Mn,Co,Ni,Cu,Hg; x=0.3,0.4,0.5,1.3,0.7) and[(Zn ttftt)Lny]n (Ln=La,Er, y=0.5; Ln=Nd,Eu, y=0.6) were prepared in absolute ethanol. The insoluble amorphous polymeric complexes have been characterized by IR spectra and X-ray photoelectron spectrometry and elemental and thermal analysis and conductivity measurements. The complexes behave as semiconductors at 25℃ as compacted pellets. Among them, the compound[(Zn-ttftt)Ni0.5 ·1.9EtOH]n showed the highest conductivity of 3.6 S/cm.
Two series of polymers based on zinc complexes of the tetrathiafulvalene tetrathiolate(ttftt4-) of stoichiometry[(Zn-ttftt)Mx]n (M=Mn,Co,Ni,Cu,Hg; x=0.3,0.4,0.5,1.3,0.7) and[(Zn ttftt)Lny]n (Ln=La,Er, y=0.5; Ln=Nd,Eu, y=0.6) were prepared in absolute ethanol. The insoluble amorphous polymeric complexes have been characterized by IR spectra and X-ray photoelectron spectrometry and elemental and thermal analysis and conductivity measurements. The complexes behave as semiconductors at 25℃ as compacted pellets. Among them, the compound[(Zn-ttftt)Ni0.5 ·1.9EtOH]n showed the highest conductivity of 3.6 S/cm.
2001, 18(8): 614-617
Abstract:
The molecular recognition properties of four chiral molecular tweezers derived from deoxycholic acid for amino acid methyl esters have been investigated by UV Vis spectroscopic titration. The association constants (Ka) and Gibbs free energy changes (-ΔG0) have been calculated. The results show that all the molecular tweezers 1~4 can form 1:1 inclusion complexes with methyl esters of D/L-phenylalanine and leucine. The recognition ability of these receptors comes mainly from hydrogen bonding and van der Waals interaction. The size/shape-fitting and geometrical complement between receptor and substrate play an important role in the inclusion complexation of amino acid methyl esters with molecular tweezers 1~4.
The molecular recognition properties of four chiral molecular tweezers derived from deoxycholic acid for amino acid methyl esters have been investigated by UV Vis spectroscopic titration. The association constants (Ka) and Gibbs free energy changes (-ΔG0) have been calculated. The results show that all the molecular tweezers 1~4 can form 1:1 inclusion complexes with methyl esters of D/L-phenylalanine and leucine. The recognition ability of these receptors comes mainly from hydrogen bonding and van der Waals interaction. The size/shape-fitting and geometrical complement between receptor and substrate play an important role in the inclusion complexation of amino acid methyl esters with molecular tweezers 1~4.
2001, 18(8): 618-622
Abstract:
6-chloro-2,4-di(N,N-(2',2',6',6'-tertamethyl-4'-piperidyl alkyl amine)-1,3,5-triazine has been synthesized from alkylated piperidineamine and cyanuric chloride by condensation reaction, then condensed with alkyl polyamine such as ethylenediamine, diethylenetriamine et al to give a series of high molecular weight piperidine-triazine compounds. A polypropylene blend with p-tert butyl calix[4]arene and high molecular weight hindered amine compound was prepared, and their thermal oxidation stability were evaluated. The blend exhibited an excellent antithermal oxidative performance due to the synergistic effects.
6-chloro-2,4-di(N,N-(2',2',6',6'-tertamethyl-4'-piperidyl alkyl amine)-1,3,5-triazine has been synthesized from alkylated piperidineamine and cyanuric chloride by condensation reaction, then condensed with alkyl polyamine such as ethylenediamine, diethylenetriamine et al to give a series of high molecular weight piperidine-triazine compounds. A polypropylene blend with p-tert butyl calix[4]arene and high molecular weight hindered amine compound was prepared, and their thermal oxidation stability were evaluated. The blend exhibited an excellent antithermal oxidative performance due to the synergistic effects.
2001, 18(8): 623-626
Abstract:
1-Bromo-2-methyloctane was obtained from diethyl malonate through hexylation, methylation, hydrolysis, decarboxylation, reduction, and bromination while 3-methyl 4-(4-methyl-1,3-dioxolan)-2-pentanone was synthesized from acetylacetone through methylation, protection of single carboxyl group. The above two compounds are the key intermediates for the synthesis of sex pheromone of Diprion pini.
1-Bromo-2-methyloctane was obtained from diethyl malonate through hexylation, methylation, hydrolysis, decarboxylation, reduction, and bromination while 3-methyl 4-(4-methyl-1,3-dioxolan)-2-pentanone was synthesized from acetylacetone through methylation, protection of single carboxyl group. The above two compounds are the key intermediates for the synthesis of sex pheromone of Diprion pini.
2001, 18(8): 627-630
Abstract:
The promotion effects of Zn,W,Cu,Cr and Ni additives on the methane aromatization performances of Mo/HZSM-5 catalyst have been investigated. Much higher conversion and selectivity for methane were observed on modified Mo-M/HZSM-5. The methods of isopropanol decomposition, NH3-TPD-MS and thermal analysis were used for characterization of the catalysts. The results appeared to be related with the methane aromatization performance that catalyst which gave high aromatics yield and good stability had fewer carbon deposit and considerable acid amount, as well as certain strong acid amount and relative strong dehydrogenating sites.
The promotion effects of Zn,W,Cu,Cr and Ni additives on the methane aromatization performances of Mo/HZSM-5 catalyst have been investigated. Much higher conversion and selectivity for methane were observed on modified Mo-M/HZSM-5. The methods of isopropanol decomposition, NH3-TPD-MS and thermal analysis were used for characterization of the catalysts. The results appeared to be related with the methane aromatization performance that catalyst which gave high aromatics yield and good stability had fewer carbon deposit and considerable acid amount, as well as certain strong acid amount and relative strong dehydrogenating sites.
2001, 18(8): 631-635
Abstract:
A conventional polyurethane-acrylate(PUA) with carboxyl as pendant group was prepared from dimethylolpropionic acid, polyethylene glycol, tolylene-2,4-diisocyanate and hydroxyethyl methacrylate. A modified PUA(g-PUA) with carboxyl group was obtained by grafting the PUA onto the copolymer of glycidyl methacrylate and methyl methacrylate through the reaction between the glycidyl and part of the carboxyl groups. The PUA and g-PUA could be easily dispersed in water in the form of self-emulsified latex after neutralization by triethylamine. The interfacial tension of the acquired dispersions was lower than that of deionized water. The investigation of photocuring on differential photocalorimeter showed that the g-PUA could polymerize to a greater extent than the conventional PUA. The glass transition termperature, thermal stability and physical properties of the cured films from the conventional PUA and the g PUA dispersions were measured. The effects of molecular weight of polyethylene glycol used on the above properties were also investigated.
A conventional polyurethane-acrylate(PUA) with carboxyl as pendant group was prepared from dimethylolpropionic acid, polyethylene glycol, tolylene-2,4-diisocyanate and hydroxyethyl methacrylate. A modified PUA(g-PUA) with carboxyl group was obtained by grafting the PUA onto the copolymer of glycidyl methacrylate and methyl methacrylate through the reaction between the glycidyl and part of the carboxyl groups. The PUA and g-PUA could be easily dispersed in water in the form of self-emulsified latex after neutralization by triethylamine. The interfacial tension of the acquired dispersions was lower than that of deionized water. The investigation of photocuring on differential photocalorimeter showed that the g-PUA could polymerize to a greater extent than the conventional PUA. The glass transition termperature, thermal stability and physical properties of the cured films from the conventional PUA and the g PUA dispersions were measured. The effects of molecular weight of polyethylene glycol used on the above properties were also investigated.
2001, 18(8): 636-639
Abstract:
Fe3+/TiO2/SiO2 complex particles with doped Fe3+ were prepared by the sol-gel method. XRD, BET, UV-vis techniques were used for their characterization and studying the influences on the heterogeneous photocatalytic degradation of nitrite. The UV light photocatalytic activity of the complex particles were found higher than those of TiO2/SiO2.The mose active catalyst was Fe3+ /TiO2/SiO2,k(Fe3+)=1.5%,m(Ti):m(Si)=2:1. It is a low crystlline anatase. The doped Fe3+ increased the particle size of titanium oxide semiconductor and lowers its stability, enhancing the light photocatalytic activity for NO2- degradation.
Fe3+/TiO2/SiO2 complex particles with doped Fe3+ were prepared by the sol-gel method. XRD, BET, UV-vis techniques were used for their characterization and studying the influences on the heterogeneous photocatalytic degradation of nitrite. The UV light photocatalytic activity of the complex particles were found higher than those of TiO2/SiO2.The mose active catalyst was Fe3+ /TiO2/SiO2,k(Fe3+)=1.5%,m(Ti):m(Si)=2:1. It is a low crystlline anatase. The doped Fe3+ increased the particle size of titanium oxide semiconductor and lowers its stability, enhancing the light photocatalytic activity for NO2- degradation.
2001, 18(8): 640-642
Abstract:
The imidazolonoxyphenoxycarboxylic esters(6a~6g) were synthesized by a new tandem aza-Wittig reaction of vinyliminophosphorane 2, aromatic isocynate and substituted phenols. The reaction has been carried out smoothly in the presence of catalytic solid potassium carbonate. The biological tests of the seven novel heterocyclic compounds showed that some of them exhibit fungicidal activities, e.g. compounds 6c and 6e showed 80% and 87% inhibitory effect on pellicularia sasakii in dosage of 50 mg/L, respectively.
The imidazolonoxyphenoxycarboxylic esters(6a~6g) were synthesized by a new tandem aza-Wittig reaction of vinyliminophosphorane 2, aromatic isocynate and substituted phenols. The reaction has been carried out smoothly in the presence of catalytic solid potassium carbonate. The biological tests of the seven novel heterocyclic compounds showed that some of them exhibit fungicidal activities, e.g. compounds 6c and 6e showed 80% and 87% inhibitory effect on pellicularia sasakii in dosage of 50 mg/L, respectively.
2001, 18(8): 643-646
Abstract:
The preparation of poly(methyl methacrylate)-b-polyacrylamide(PMMA-b-PAAM) using 4,4'-azobis[4-cyanopentanoyl(p-dimethyl amino) anilide](ACPDA) as an initiator was investigated. At 70℃, ACPDA initiated methyl methacrylate(MMA) to give a PMMA prepolymer containing N,N dimethyl anilide terminal group(DMA). The redox system of the PMMA/benzoyl peroxide(BPO) could initiate the polymerization of acrylamide(AAM) to give PMMA-b-PAAM. The block copolymer was characterized by IR, TG, DTA, PGC and SEM. The PMMA-b-PAAM showed a better thermal stability than PMMA homopolymer.
The preparation of poly(methyl methacrylate)-b-polyacrylamide(PMMA-b-PAAM) using 4,4'-azobis[4-cyanopentanoyl(p-dimethyl amino) anilide](ACPDA) as an initiator was investigated. At 70℃, ACPDA initiated methyl methacrylate(MMA) to give a PMMA prepolymer containing N,N dimethyl anilide terminal group(DMA). The redox system of the PMMA/benzoyl peroxide(BPO) could initiate the polymerization of acrylamide(AAM) to give PMMA-b-PAAM. The block copolymer was characterized by IR, TG, DTA, PGC and SEM. The PMMA-b-PAAM showed a better thermal stability than PMMA homopolymer.
2001, 18(8): 647-650
Abstract:
A series of five-membered phosphorusheterocycles were synthesized by reacting tris(diethylamino) phosphine with T-aminoacetamides. Their structures were characterized by elemental analysis and 1H NMR, some by MS, IR and 31P NMR as well. The preliminary bioassays show that these compounds possess good selective herbicidal activity and some of them also have had antivirus and fungicidal activities.
A series of five-membered phosphorusheterocycles were synthesized by reacting tris(diethylamino) phosphine with T-aminoacetamides. Their structures were characterized by elemental analysis and 1H NMR, some by MS, IR and 31P NMR as well. The preliminary bioassays show that these compounds possess good selective herbicidal activity and some of them also have had antivirus and fungicidal activities.
2001, 18(8): 651-654
Abstract:
Fourteen N-aryl N'-(6 chloropyridine-3-yl)methylthioureas were prepared, their compositions and structures were confirmed by elemental analysis, IR, and 1H NMR measurements. The plant growth activating effects on cucumber, rice and insecticidal activities on Musca domestica have been tested preliminarily.
Fourteen N-aryl N'-(6 chloropyridine-3-yl)methylthioureas were prepared, their compositions and structures were confirmed by elemental analysis, IR, and 1H NMR measurements. The plant growth activating effects on cucumber, rice and insecticidal activities on Musca domestica have been tested preliminarily.
2001, 18(8): 655-658
Abstract:
The Ti-promoted sulfur-tolerant water-gas-shift catalyst has been studied in micro-reactor system as function of activity and anti hydration by using TPR、SEM、XRD、IR techniques. The results show that an appropriate amount of TiO2 in the carrier of catalyst can transform much more number of the inactive Mo6+ in the catalyst into the active ones such as Mo5+ and Mo4+, obviously increasing the catalytic activity. Meanwhile, the strength of L-acid absorption sites on the surface of the Al2O3 can be effectively weakened, so that the carrier's ability to react with water is weakened, and the anti-hydration of catalyst can be sharply enhanced.
The Ti-promoted sulfur-tolerant water-gas-shift catalyst has been studied in micro-reactor system as function of activity and anti hydration by using TPR、SEM、XRD、IR techniques. The results show that an appropriate amount of TiO2 in the carrier of catalyst can transform much more number of the inactive Mo6+ in the catalyst into the active ones such as Mo5+ and Mo4+, obviously increasing the catalytic activity. Meanwhile, the strength of L-acid absorption sites on the surface of the Al2O3 can be effectively weakened, so that the carrier's ability to react with water is weakened, and the anti-hydration of catalyst can be sharply enhanced.
2001, 18(8): 659-661
Abstract:
The standard formation enthalpy of the glycine complex with erbium chloride was determined by using an isoperibolic calorimeter with the hydrochloric acid solution(2 mol/L) as a calorimetric solvent according a proposed thermochemical cycle. The following values were obtained: ΔrHmθ(298.15 K)=-3.331 kJ/mol ΔfHmθ(Er(Gly)3Cl3·3H2O,s,298.15 K)=-3 632.0 kJ/mol
The standard formation enthalpy of the glycine complex with erbium chloride was determined by using an isoperibolic calorimeter with the hydrochloric acid solution(2 mol/L) as a calorimetric solvent according a proposed thermochemical cycle. The following values were obtained: ΔrHmθ(298.15 K)=-3.331 kJ/mol ΔfHmθ(Er(Gly)3Cl3·3H2O,s,298.15 K)=-3 632.0 kJ/mol
2001, 18(8): 662-663
Abstract:
Using an available compound 3-pentanone(1) as starting material, the key intermediate compound 4,6-dimethyl-3,7-nonandione(5) was synthesized through the additionelimination of silylenol ether and Michael addition of T-methylene 3-pentanone(4) with silylenol ether(2). In the presence of chiral reagent 6U-phenyl amino-3U,5T-chlorestandiol(7), compound (5) was reduced by KBH4 directly to give Tobacco Beetle Pheromone (7S)-(-)-4,6-dimethyl-7-hydroxyl-3-nonanone(6). [T]D25=-35.87°(c=0.23, CHCl3), overall yield 23.9%.
Using an available compound 3-pentanone(1) as starting material, the key intermediate compound 4,6-dimethyl-3,7-nonandione(5) was synthesized through the additionelimination of silylenol ether and Michael addition of T-methylene 3-pentanone(4) with silylenol ether(2). In the presence of chiral reagent 6U-phenyl amino-3U,5T-chlorestandiol(7), compound (5) was reduced by KBH4 directly to give Tobacco Beetle Pheromone (7S)-(-)-4,6-dimethyl-7-hydroxyl-3-nonanone(6). [T]D25=-35.87°(c=0.23, CHCl3), overall yield 23.9%.
2001, 18(8): 664-666
Abstract:
Ten N1-pyridylmethyl-N-arylacyl-urea derivatives were synthesized by the nucleophilic addition reaction of N-alkyl-(2-chloro-5-pyridylmethyl)amine with 2,6-difluorophenylacyl isocyanate, and characterized by IR, 1H NMR and elemental analysis. Preliminary biological tests showed that these compounds have good insecticidal activity against Nephotettix cincticeps and Mosquito larvae, especially, compounds 3f and 3j which could give 100% mortality for Nephotettix cincticeps in dosage with mass fraction of 5×10-5%.
Ten N1-pyridylmethyl-N-arylacyl-urea derivatives were synthesized by the nucleophilic addition reaction of N-alkyl-(2-chloro-5-pyridylmethyl)amine with 2,6-difluorophenylacyl isocyanate, and characterized by IR, 1H NMR and elemental analysis. Preliminary biological tests showed that these compounds have good insecticidal activity against Nephotettix cincticeps and Mosquito larvae, especially, compounds 3f and 3j which could give 100% mortality for Nephotettix cincticeps in dosage with mass fraction of 5×10-5%.
2001, 18(8): 667-669
Abstract:
The viscosity behavior of the sulfonated polystyrene lanthanum ionomers(SPS-La) has been investigated in comparison with the sodium and zinc ionomers in polar solvents. The results indicated that the SPS-La with the same sulfonation degree exhibited higher reduced viscosity and intrinsic viscosity when the polarity of the solvents was high. The lower the sulfonation degree of SPS-La, the higher the reduced viscosity of SPS-La, especially in case of estremely dilute dolutions. The order of the reduced viscosity and the polyelectrolyte effect tendency are:SPS-Na > SPS-Zn > SPS > SPS-La.
The viscosity behavior of the sulfonated polystyrene lanthanum ionomers(SPS-La) has been investigated in comparison with the sodium and zinc ionomers in polar solvents. The results indicated that the SPS-La with the same sulfonation degree exhibited higher reduced viscosity and intrinsic viscosity when the polarity of the solvents was high. The lower the sulfonation degree of SPS-La, the higher the reduced viscosity of SPS-La, especially in case of estremely dilute dolutions. The order of the reduced viscosity and the polyelectrolyte effect tendency are:SPS-Na > SPS-Zn > SPS > SPS-La.
2001, 18(8): 670-672
Abstract:
The interaction of O-{2-[α(2-hydroxy-5-sulphophenylazo)benzylidene]hydrazino}benzoic acid(ZCN) with cetyl trimethyl ammonium bromide(CTAB) was studied by UV spectra in pH=5.0 buffered solution. The results showed the complex has maximum absorption at 540 and 570 nm with an apparent molar absorptivity of 2 0×104L/(mol·cm). Three constants were determined:binding constant K=2.3×105; degree of dissociation T=0.03 and binding number n(CTAB):n(ZCN)=1:2.5.
The interaction of O-{2-[α(2-hydroxy-5-sulphophenylazo)benzylidene]hydrazino}benzoic acid(ZCN) with cetyl trimethyl ammonium bromide(CTAB) was studied by UV spectra in pH=5.0 buffered solution. The results showed the complex has maximum absorption at 540 and 570 nm with an apparent molar absorptivity of 2 0×104L/(mol·cm). Three constants were determined:binding constant K=2.3×105; degree of dissociation T=0.03 and binding number n(CTAB):n(ZCN)=1:2.5.
2001, 18(8): 673-674
Abstract:
The catalytic activities of some solid acid catalysts, H-β, HZSM-5 and HY zeolites, in the esterification of benzyl alcohol with acetic acid were investigated as functions of the molar ratio of benzyl alcohol to acetic acid, the feed amount of H-β zeolite, and reaction temperature and time. A maximum yield of benzyl acetate in 70% was obtained under certain reaction conditions. The H-β zeolite could be used repeatedly at least 5 times after regeneration.
The catalytic activities of some solid acid catalysts, H-β, HZSM-5 and HY zeolites, in the esterification of benzyl alcohol with acetic acid were investigated as functions of the molar ratio of benzyl alcohol to acetic acid, the feed amount of H-β zeolite, and reaction temperature and time. A maximum yield of benzyl acetate in 70% was obtained under certain reaction conditions. The H-β zeolite could be used repeatedly at least 5 times after regeneration.
2001, 18(8): 675-677
Abstract:
A series of porous crosslinked acrylic acid copolymer beads was prepared directly by suspension polymerization of acrylic acid in the presence of 1,2-dichloroethane, toluene or heptane as the inert diluents and divinylbenzene and triallyl isocyanurate as crosslinking agents. A 45% aqueous CaCl2 solution containing 0.2% hydroxyethyl cellulose was used as the water phase. The copoly merization gave a yield more than 90% and copolymers withion-exchange capacity of 12 mmol/g were obtained. The effects of synthesis conditions,including the ratio of monomer to diluent, reaction temperture, on the resin properties were examined.
A series of porous crosslinked acrylic acid copolymer beads was prepared directly by suspension polymerization of acrylic acid in the presence of 1,2-dichloroethane, toluene or heptane as the inert diluents and divinylbenzene and triallyl isocyanurate as crosslinking agents. A 45% aqueous CaCl2 solution containing 0.2% hydroxyethyl cellulose was used as the water phase. The copoly merization gave a yield more than 90% and copolymers withion-exchange capacity of 12 mmol/g were obtained. The effects of synthesis conditions,including the ratio of monomer to diluent, reaction temperture, on the resin properties were examined.
2001, 18(8): 678-680
Abstract:
1-Methyl-1-phenyl-1-[3-(3-phenoxyl)-phenyl]cyclopentene ethane (9) as a non-ester pyrethroid was synthesized via a series of reactions from available materials e.g. cyclopentanone with advantages of good yield and easy operation. The structure of the compound was confirmed by elemental analysis? IR and 1H NMR.
1-Methyl-1-phenyl-1-[3-(3-phenoxyl)-phenyl]cyclopentene ethane (9) as a non-ester pyrethroid was synthesized via a series of reactions from available materials e.g. cyclopentanone with advantages of good yield and easy operation. The structure of the compound was confirmed by elemental analysis? IR and 1H NMR.
