Login In
1995 Volume 12 Issue 2
1995, 12(2): 1-4
Abstract:
The hydrolysis-condensation process of Pb-Ti complex alkoxide has been studied by turbidimetry. It was found that increase in both the amount of water and alkoxide concen-tration accelerated the hydrolysis-condensation reaction. NH4OH greatly promoted the hy-drolysis-condensation reaction,while HOAc showed a promotion effect at lower acid concen-tration,but a suppression effect at higher acid concentration. The results have been ex-plained in terms of hydrolysis-condensation reaction of alkoxide.
The hydrolysis-condensation process of Pb-Ti complex alkoxide has been studied by turbidimetry. It was found that increase in both the amount of water and alkoxide concen-tration accelerated the hydrolysis-condensation reaction. NH4OH greatly promoted the hy-drolysis-condensation reaction,while HOAc showed a promotion effect at lower acid concen-tration,but a suppression effect at higher acid concentration. The results have been ex-plained in terms of hydrolysis-condensation reaction of alkoxide.
1995, 12(2): 5-8
Abstract:
The M-S (M=Mo,W) cluster compound films on copper surfaces have been in-vestigated by FTIR, XPS and AES. The results show that Mo(W)-S-Cu bonds were formed by the reaction of Mo(W)S42- with Cu2O layer on copper surface. The films are com-posed of Mo(W),S,Cu and O,each with the valence of +6,-2,+1 and -2,respective-ly. A multimolecular layer structure of the films was verified. Only Cu and O were found on the film surface, MoS4 or WS2 units remain in the inner layers of the films. The thickness of the film was found to depend on the reaction time: the longer the time,the thicker the film. The color of the films is probably caused by a statistical distribution of various layers and the film is a complicated multicomponent and multilayer system.
The M-S (M=Mo,W) cluster compound films on copper surfaces have been in-vestigated by FTIR, XPS and AES. The results show that Mo(W)-S-Cu bonds were formed by the reaction of Mo(W)S42- with Cu2O layer on copper surface. The films are com-posed of Mo(W),S,Cu and O,each with the valence of +6,-2,+1 and -2,respective-ly. A multimolecular layer structure of the films was verified. Only Cu and O were found on the film surface, MoS4 or WS2 units remain in the inner layers of the films. The thickness of the film was found to depend on the reaction time: the longer the time,the thicker the film. The color of the films is probably caused by a statistical distribution of various layers and the film is a complicated multicomponent and multilayer system.
1995, 12(2): 9-12
Abstract:
The adsorption of heteropoly acid (HPA) SiW12 of Keggin structure on the acti-vated carbons of different sources has been studied in aqueous solutions of H2SO4, HCl, H3PO4 with H+ concentration of 3mol/L,aq. HAc solution and pure acetic acid. It is found that the forms of the adsorption isotherms of SiW12 were different and the micropore struc-ture of the adsorbent and solvation of HPA have an important effect on HPA adsorption. In inorganic acid medium the amount of the adsorbed HPA was higher than it was in water, and there appeared a proportional relation between adsorptive capacity and acid strength of the medium. In organic acid medium the adsorption was more complex. An adsorption model of HPA in acid medium is proposed.
The adsorption of heteropoly acid (HPA) SiW12 of Keggin structure on the acti-vated carbons of different sources has been studied in aqueous solutions of H2SO4, HCl, H3PO4 with H+ concentration of 3mol/L,aq. HAc solution and pure acetic acid. It is found that the forms of the adsorption isotherms of SiW12 were different and the micropore struc-ture of the adsorbent and solvation of HPA have an important effect on HPA adsorption. In inorganic acid medium the amount of the adsorbed HPA was higher than it was in water, and there appeared a proportional relation between adsorptive capacity and acid strength of the medium. In organic acid medium the adsorption was more complex. An adsorption model of HPA in acid medium is proposed.
1995, 12(2): 13-15
Abstract:
A series of Schiff base coordination compounds containing Cu,Ni,Zn,and Co has been synthesized from salicylaldehyde,2,4-dihydroxy benzaldehyde, glycine and L-ala-nine. The order of the antitumor activity of the conlpounds is Ni>Cu>Zn>Co,by ethidium fluorescence spectroscopy.
A series of Schiff base coordination compounds containing Cu,Ni,Zn,and Co has been synthesized from salicylaldehyde,2,4-dihydroxy benzaldehyde, glycine and L-ala-nine. The order of the antitumor activity of the conlpounds is Ni>Cu>Zn>Co,by ethidium fluorescence spectroscopy.
1995, 12(2): 16-19
Abstract:
The stacking interaction of aromatic rings in the mixed ligand complexes Pd(A) (ATP)n- (A=1,10-phenanthroline,2,2'-bipyridyl,and typtophane,n=2,3) has been studied by 1H NMR. The results showed that the stacking degree was in accordance with the size of the aromatic rings.
The stacking interaction of aromatic rings in the mixed ligand complexes Pd(A) (ATP)n- (A=1,10-phenanthroline,2,2'-bipyridyl,and typtophane,n=2,3) has been studied by 1H NMR. The results showed that the stacking degree was in accordance with the size of the aromatic rings.
1995, 12(2): 20-23
Abstract:
Zirconium dibutylaminomethylphosphonate-phosphites Zr(HPO3)2-x·(O3PCH2N-Bu2)x·H2O (ZPDBN-ZP,x=0.8,0.6,0.5,0.4,0.35) have been prepared for the first time. Partly quaternized ZPDBN-ZP with benzylbromide, zirconium (benzyldibutylammo-niomethylphosphonate bromide-dibutylammoniomethylphosphonate-phosphite) Zr(HPO3)2-x·(O3PCH2NBu2)x-y·(O3PCH2N+Bu2PhCH2Br-)y·H2O (ZPBBDB-ZPDBN-ZP, y< x) have been obtained. Heterogeneous PTC reactions of nucleophilic substitution, etherifica-tion,esterification, and addition of dichlorocarbene by using ZPBBDB-ZPDBN-ZP have been carried out successfully. The catalysts can easily be recovered with recovery of 70%~100%. No obvious loss of the catalytic activity was found after more than ten times repeated use.
Zirconium dibutylaminomethylphosphonate-phosphites Zr(HPO3)2-x·(O3PCH2N-Bu2)x·H2O (ZPDBN-ZP,x=0.8,0.6,0.5,0.4,0.35) have been prepared for the first time. Partly quaternized ZPDBN-ZP with benzylbromide, zirconium (benzyldibutylammo-niomethylphosphonate bromide-dibutylammoniomethylphosphonate-phosphite) Zr(HPO3)2-x·(O3PCH2NBu2)x-y·(O3PCH2N+Bu2PhCH2Br-)y·H2O (ZPBBDB-ZPDBN-ZP, y< x) have been obtained. Heterogeneous PTC reactions of nucleophilic substitution, etherifica-tion,esterification, and addition of dichlorocarbene by using ZPBBDB-ZPDBN-ZP have been carried out successfully. The catalysts can easily be recovered with recovery of 70%~100%. No obvious loss of the catalytic activity was found after more than ten times repeated use.
1995, 12(2): 24-28
Abstract:
The discharge and cyclic voltammetry behavior of a variety of zeolites as cathode of lithium secondary cell have been studied by coulometric titration,infrared absorption spectrosoepy and X-ray diffractometry. It was found that in the course of discharge lithium is electrochemically intercalated into compound at discharge depth x < 3.4mol. The intercala-tion free energy of Li into NaA zeolite was found to be -231kJ/mol (25℃). The chemical diffusion coefficient of lithium in LixNaA (x=0.17~0.69) was determined to be about 1×10-9~1×10-10cm2/s at room temperature.
The discharge and cyclic voltammetry behavior of a variety of zeolites as cathode of lithium secondary cell have been studied by coulometric titration,infrared absorption spectrosoepy and X-ray diffractometry. It was found that in the course of discharge lithium is electrochemically intercalated into compound at discharge depth x < 3.4mol. The intercala-tion free energy of Li into NaA zeolite was found to be -231kJ/mol (25℃). The chemical diffusion coefficient of lithium in LixNaA (x=0.17~0.69) was determined to be about 1×10-9~1×10-10cm2/s at room temperature.
1995, 12(2): 29-32
Abstract:
Ten dicyclohexylmethyltin-O,O-dialkyl(aryl)dithiophosphates have been prepared and characterized by IR,NMR (1H, 13C),MS and elemental analysis. The bioassay tests showed the high acaricidal activities and herbicidal activities of the compounds.
Ten dicyclohexylmethyltin-O,O-dialkyl(aryl)dithiophosphates have been prepared and characterized by IR,NMR (1H, 13C),MS and elemental analysis. The bioassay tests showed the high acaricidal activities and herbicidal activities of the compounds.
1995, 12(2): 33-36
Abstract:
The surface of Nafion membrane can be rendered more hydrophilic by modification with perfluorinated surfactants. A surfactant of sulfonic acid type (FC-99) was found to be most suitable for membrane modification. The swelling of the membrane is not serious after treatment, while the advancing contact angle between water and the membrane can be signi-ficantly reduced. Bubble effect ("zero-gap" effect) was diminished markedly in experimental membrane electrolysis cell using modified Nafion membrane.
The surface of Nafion membrane can be rendered more hydrophilic by modification with perfluorinated surfactants. A surfactant of sulfonic acid type (FC-99) was found to be most suitable for membrane modification. The swelling of the membrane is not serious after treatment, while the advancing contact angle between water and the membrane can be signi-ficantly reduced. Bubble effect ("zero-gap" effect) was diminished markedly in experimental membrane electrolysis cell using modified Nafion membrane.
1995, 12(2): 37-41
Abstract:
Two ligands 1,6-diferrocenyl-2,5-diazahexane and 1,1,6,6-tetraferrocenyl-2,5-diazahexane,were synthesized by reacting ethylene diamine with ferrocenyl formaldehyde and biferrocenylmethyl flouroborate respectively. Fourteen complexes of the ligands with Fe2+,Co2+,Ni2+,Cu2+ and Zn2+ were prepared. All the compounds have been characterized by elemental analysis, DTA and IR,1H NMR measurements. The ligands and their cuprous complex have been used as burning-rate modifiers for composite solid propellants. No migra-tion was found in composite propellants. The catalytic efficiency of burning-rate was over that of octylferrocene.
Two ligands 1,6-diferrocenyl-2,5-diazahexane and 1,1,6,6-tetraferrocenyl-2,5-diazahexane,were synthesized by reacting ethylene diamine with ferrocenyl formaldehyde and biferrocenylmethyl flouroborate respectively. Fourteen complexes of the ligands with Fe2+,Co2+,Ni2+,Cu2+ and Zn2+ were prepared. All the compounds have been characterized by elemental analysis, DTA and IR,1H NMR measurements. The ligands and their cuprous complex have been used as burning-rate modifiers for composite solid propellants. No migra-tion was found in composite propellants. The catalytic efficiency of burning-rate was over that of octylferrocene.
1995, 12(2): 42-46
Abstract:
A novel ligand 2,6-bis (1'-phenyl-3'-methyl-5'-oxo-4'-formylpyrazol) pyridine (H2L) and its complexes have been prepared by reacting H2L with rare earth nitrate in ethyl alcohol solution. The complexes have been characterized by elemental analysis, thermoanal-ysis,molar conductivity,IR,UV,1H NMR and fluorescence spectra measurements.
A novel ligand 2,6-bis (1'-phenyl-3'-methyl-5'-oxo-4'-formylpyrazol) pyridine (H2L) and its complexes have been prepared by reacting H2L with rare earth nitrate in ethyl alcohol solution. The complexes have been characterized by elemental analysis, thermoanal-ysis,molar conductivity,IR,UV,1H NMR and fluorescence spectra measurements.
1995, 12(2): 47-50
Abstract:
Nine aryl β-aryloxypropionates and eight ary β-aryloxypropionamides have been synthesized and confirmed by elemental analysis,UV,IR, and 1H NMR spectrometry mea-surements. The promoting effects of these compounds on the wheat growth were tested pre-liminary.
Nine aryl β-aryloxypropionates and eight ary β-aryloxypropionamides have been synthesized and confirmed by elemental analysis,UV,IR, and 1H NMR spectrometry mea-surements. The promoting effects of these compounds on the wheat growth were tested pre-liminary.
1995, 12(2): 51-54
Abstract:
The production of micronized cellulose by acid hydrolysis induced the changes in main structural characteristics,such as degree of polymerization,crystallinity,size of crys-tallites and morphological structure,which depend greatly on the original crystalline types and means of the treatment. The results from X-ray diffraction showed that the biphase sys-tem still remains in the micronized celluloses,so their original crystalline type.
The production of micronized cellulose by acid hydrolysis induced the changes in main structural characteristics,such as degree of polymerization,crystallinity,size of crys-tallites and morphological structure,which depend greatly on the original crystalline types and means of the treatment. The results from X-ray diffraction showed that the biphase sys-tem still remains in the micronized celluloses,so their original crystalline type.
1995, 12(2): 55-58
Abstract:
The LB films of two fluorescent molectiles,4-dicyanomethylene-2-methyl-6-p-dimethylaminostyryl-4H-pyran (DCM) and 1,2-bis(5-methylbenzoxazol-2-yl) ethylene (DT) and their mixture were prepared. The configtiration, micro environment and luminescence properties of these molecules in films have been investigated by absorption and fluorcscence spectroscopy. The content of cis-form DCM in LB film was found to be greatly increascd in comparison with that in solution.
The LB films of two fluorescent molectiles,4-dicyanomethylene-2-methyl-6-p-dimethylaminostyryl-4H-pyran (DCM) and 1,2-bis(5-methylbenzoxazol-2-yl) ethylene (DT) and their mixture were prepared. The configtiration, micro environment and luminescence properties of these molecules in films have been investigated by absorption and fluorcscence spectroscopy. The content of cis-form DCM in LB film was found to be greatly increascd in comparison with that in solution.
1995, 12(2): 59-62
Abstract:
The ESR spectra of VO-Glu and VO-Glu-phen systems in glycol/water(1:1) mixture with various acidity have been recorded at 173K. It is found that the constitution of the complexes is in dependence on the pH values of the solution. Their possible structures were suggested according to Johnson's rule and IR values. By using electronic spectral data the crystal field parameters were calculated.
The ESR spectra of VO-Glu and VO-Glu-phen systems in glycol/water(1:1) mixture with various acidity have been recorded at 173K. It is found that the constitution of the complexes is in dependence on the pH values of the solution. Their possible structures were suggested according to Johnson's rule and IR values. By using electronic spectral data the crystal field parameters were calculated.
1995, 12(2): 63-66
Abstract:
Twenty one α-thiophosphorylamidocetamidcs with general formula [RO(R1O)P (S)N(Et)CH2CON(C3H7)2] have been synthesized by reacting RO(R1O)P(S)Cl with EtNHCH2CON(C3H7)2 and characterized by elemental analysis,1H NMR and 31 P NMR mea-surements. They showed a better acaricidal and insecticidal activity.
Twenty one α-thiophosphorylamidocetamidcs with general formula [RO(R1O)P (S)N(Et)CH2CON(C3H7)2] have been synthesized by reacting RO(R1O)P(S)Cl with EtNHCH2CON(C3H7)2 and characterized by elemental analysis,1H NMR and 31 P NMR mea-surements. They showed a better acaricidal and insecticidal activity.
1995, 12(2): 67-71
Abstract:
Nanosized stannic oxide powders were prepared by sol-gel method. The mi-crostructure change of the ultrafine particles after heat-treatment at 300~800℃ has been in-vestigated by XRD,TEM,TG-DTA,and FT-IR techniques. It is found that the intensity of the transverse optical mode of Sn-O streching vibration increased with the calcining tempcr-ature and the bonding vibration of O-Sn-O showed a blue shift. The changes are strongly affected by the size, shape, and the state of aggregation of the ultrafine particles.
Nanosized stannic oxide powders were prepared by sol-gel method. The mi-crostructure change of the ultrafine particles after heat-treatment at 300~800℃ has been in-vestigated by XRD,TEM,TG-DTA,and FT-IR techniques. It is found that the intensity of the transverse optical mode of Sn-O streching vibration increased with the calcining tempcr-ature and the bonding vibration of O-Sn-O showed a blue shift. The changes are strongly affected by the size, shape, and the state of aggregation of the ultrafine particles.
1995, 12(2): 72-75
Abstract:
A polyester/polyurethane interpenetrating polymer network (IPN) was prepared from acetoxy terminated unsaturated polyester(FUPR) and crosslinked polyurethaiie pre-polymer. The kinetics of network formation, behavior of rnicrophase separation and mecha-nical properties of the IPNs were examined by IR,DSC,and SEM. The results showed that the IPN was formed at a certain ratio of FUPR/PU. The products showed an improved ri-gidity to polyutrethane and increased impact strength to unsaturated polyester.
A polyester/polyurethane interpenetrating polymer network (IPN) was prepared from acetoxy terminated unsaturated polyester(FUPR) and crosslinked polyurethaiie pre-polymer. The kinetics of network formation, behavior of rnicrophase separation and mecha-nical properties of the IPNs were examined by IR,DSC,and SEM. The results showed that the IPN was formed at a certain ratio of FUPR/PU. The products showed an improved ri-gidity to polyutrethane and increased impact strength to unsaturated polyester.
1995, 12(2): 76-79
Abstract:
The influences of addition of La2O3 and Y2O3 on the crystallization and melting be-havior of MC nvlon-6 have been studied by DSC technique at a rate of 10℃/min. Both rare earth oxides increased the crvstallization temperattire Tc and decreascd the melting tempera-ture Tm of MC nylon-6,decreased the crystallinity Xc. Addition of La2O3 decreased the equi-librlum melting temperature Tmo,leading to the increased crystallization rate and imperfect-ness of the crvstallization. Adtlition of Y2O3 increased the Tmo, remarkedly improving the thermal stability of MC nylon-6.
The influences of addition of La2O3 and Y2O3 on the crystallization and melting be-havior of MC nvlon-6 have been studied by DSC technique at a rate of 10℃/min. Both rare earth oxides increased the crvstallization temperattire Tc and decreascd the melting tempera-ture Tm of MC nylon-6,decreased the crystallinity Xc. Addition of La2O3 decreased the equi-librlum melting temperature Tmo,leading to the increased crystallization rate and imperfect-ness of the crvstallization. Adtlition of Y2O3 increased the Tmo, remarkedly improving the thermal stability of MC nylon-6.
1995, 12(2): 80-83
Abstract:
Three kinds of clay were fractionated according to the particle size using ultrasonic and centrifugal method. The mechanical properties of the clay-rubber masterbatch with vari-ous clay fractions were determined. The results show that within a certain range,the clay particle size only affects some of the mechanical properties of clay-rubber masterbatch. The characteristic morphological structure of the clay provides a significant reinforcing action on clay-rubber masterbatch.
Three kinds of clay were fractionated according to the particle size using ultrasonic and centrifugal method. The mechanical properties of the clay-rubber masterbatch with vari-ous clay fractions were determined. The results show that within a certain range,the clay particle size only affects some of the mechanical properties of clay-rubber masterbatch. The characteristic morphological structure of the clay provides a significant reinforcing action on clay-rubber masterbatch.
1995, 12(2): 84-87
Abstract:
The morphology and mechanical properties of PES-C/PPS blends have been stud-ied by means of DSC,DMA,SEM and mechanical characterization. The blends are partly compatible. It is interested that, though the strength and ductility of PPS is lower than that of PES-C, at low content of PPS the impact strength of PES-C can be improved markedly without changing its tensile strength and elongation at break. The melt index of the blends also increases with increasing PPS content.
The morphology and mechanical properties of PES-C/PPS blends have been stud-ied by means of DSC,DMA,SEM and mechanical characterization. The blends are partly compatible. It is interested that, though the strength and ductility of PPS is lower than that of PES-C, at low content of PPS the impact strength of PES-C can be improved markedly without changing its tensile strength and elongation at break. The melt index of the blends also increases with increasing PPS content.
1995, 12(2): 88-91
Abstract:
The thermal and crystallization behaviour of HDPE/LDPE/EVA blends have been studied by DSC and WAXD technigues. The results showed that when HDPE content was less than 40%, the EVA as a diluent for the LDPE,promotes crystal phase separation of HDPE and LDPE: when the content of HDPE was more than 40%,LDPE may enter into HDPE crystalline regions,forming cocrystallite in the lamellar regian.
The thermal and crystallization behaviour of HDPE/LDPE/EVA blends have been studied by DSC and WAXD technigues. The results showed that when HDPE content was less than 40%, the EVA as a diluent for the LDPE,promotes crystal phase separation of HDPE and LDPE: when the content of HDPE was more than 40%,LDPE may enter into HDPE crystalline regions,forming cocrystallite in the lamellar regian.
1995, 12(2): 92-94
Abstract:
3'-Allyldibenzo-18-crown-6,prepared from 3-allylcatechol and 1,2-bis(β-(β'-chloroethoxy)-ethoxy) benzene,was subjected to hydrosilylation by methyldichlorosiloxane,followed by polycondensation with hydroxy-terminated polydimethylsiloxane to give a linear polysiloxane with pendant crown ether moieties. The transport properties of sodium,potas-sium,and ammonium salts throtigh a bulk liquid membrane system using this polysiloxane as a carrier have been investigated.
3'-Allyldibenzo-18-crown-6,prepared from 3-allylcatechol and 1,2-bis(β-(β'-chloroethoxy)-ethoxy) benzene,was subjected to hydrosilylation by methyldichlorosiloxane,followed by polycondensation with hydroxy-terminated polydimethylsiloxane to give a linear polysiloxane with pendant crown ether moieties. The transport properties of sodium,potas-sium,and ammonium salts throtigh a bulk liquid membrane system using this polysiloxane as a carrier have been investigated.
1995, 12(2): 95-97
Abstract:
The molybdenum(Ⅳ) oxides of formula Ln2Mo3O9 were obtained by reduction of α-Ln2Mo3O12(Ln=La,Pr,Nd, Sm,Gd,Dy) as well as Ce2Mo3O12.25 in hydrogen at 500~650℃ for 60 hours. The compounds are of single phase and crystallize in tetragonal structure with parameters α=0.5260nm~0.5131nm and c=1.18211nm~1.1122nm. There are two broad absorption bands in the IR spectra of the Ln2Mo3O9. All of the compounds are n-type semiconductors with ρr.t. =92.13Ωcm~7.51Ωcm. Their electrical properties at 10~350℃ and magnetic properties at 100~250K were measured.
The molybdenum(Ⅳ) oxides of formula Ln2Mo3O9 were obtained by reduction of α-Ln2Mo3O12(Ln=La,Pr,Nd, Sm,Gd,Dy) as well as Ce2Mo3O12.25 in hydrogen at 500~650℃ for 60 hours. The compounds are of single phase and crystallize in tetragonal structure with parameters α=0.5260nm~0.5131nm and c=1.18211nm~1.1122nm. There are two broad absorption bands in the IR spectra of the Ln2Mo3O9. All of the compounds are n-type semiconductors with ρr.t. =92.13Ωcm~7.51Ωcm. Their electrical properties at 10~350℃ and magnetic properties at 100~250K were measured.
1995, 12(2): 98-100
Abstract:
The crystallization of polycaprolactone (PCL),polyethylene glycol (PEG) and their block copolymers have been studied using DSC technique. The results showed that the composition as well as the molecular weight of PCL and PEG affected the crystallinity of the block copolymers. The crystallinity of the copolymer showed a maximum value on standing. Some of the kinetic parameters on isothermo-crystallization have been calculated.
The crystallization of polycaprolactone (PCL),polyethylene glycol (PEG) and their block copolymers have been studied using DSC technique. The results showed that the composition as well as the molecular weight of PCL and PEG affected the crystallinity of the block copolymers. The crystallinity of the copolymer showed a maximum value on standing. Some of the kinetic parameters on isothermo-crystallization have been calculated.
1995, 12(2): 101-103
Abstract:
NaBH3CN-ZnCl2 was applied for the selective reduction deoxygenation of hydroxyl and carbonyl groups in ferrocene derivatives under mild condition without affecting on the carboxy groups. The molar ratio of B/Fe and Zn/Fe,as well as the solvents showed impor-tant influences on the deoxygenation. The possible intermediates were suggested.
NaBH3CN-ZnCl2 was applied for the selective reduction deoxygenation of hydroxyl and carbonyl groups in ferrocene derivatives under mild condition without affecting on the carboxy groups. The molar ratio of B/Fe and Zn/Fe,as well as the solvents showed impor-tant influences on the deoxygenation. The possible intermediates were suggested.
1995, 12(2): 104-106
Abstract:
The alcohol-soluble polyamide resins have been obtained by copolymerization of a mixture comprising polymeric fatty acid,ricinoleic acid and sebacic acid with ethylenediamine and 1,3-diamino-2-hydroxypropane. In an appropriate proportion of ricinoleic acid to 1,3-di-amino-2-hydroxypropane the polymerized product exhibits an improved low temperature sol-ubility in lower molecular aliphatic alcohols and higher softening point.
The alcohol-soluble polyamide resins have been obtained by copolymerization of a mixture comprising polymeric fatty acid,ricinoleic acid and sebacic acid with ethylenediamine and 1,3-diamino-2-hydroxypropane. In an appropriate proportion of ricinoleic acid to 1,3-di-amino-2-hydroxypropane the polymerized product exhibits an improved low temperature sol-ubility in lower molecular aliphatic alcohols and higher softening point.
1995, 12(2): 107-109
Abstract:
The conditions of extraction of tea-polyphenols (TP) from tea dusts by precipita-tion method using metal ions Ca2+,Mg2+,Ba2+,Fe3+,Zn2+ and Al3+ as precipitating agents have been investigated. The influences of pH value,temperture,time,type and content of basic solutions used to regulate the pH value on the extraction rate of TP were examined. It is shown that the extraction rate of TP could reach 10.5% and the content of the effective in-gredients of TP could reach 99.5% by the proposed method.
The conditions of extraction of tea-polyphenols (TP) from tea dusts by precipita-tion method using metal ions Ca2+,Mg2+,Ba2+,Fe3+,Zn2+ and Al3+ as precipitating agents have been investigated. The influences of pH value,temperture,time,type and content of basic solutions used to regulate the pH value on the extraction rate of TP were examined. It is shown that the extraction rate of TP could reach 10.5% and the content of the effective in-gredients of TP could reach 99.5% by the proposed method.
1995, 12(2): 110-112
Abstract:
The adsorption of gold-thiourea complex ions by activated carbon in solution has been studied. The adsorption rate curves and isothems were obtained and the effects of pH values of the solution and foreign ions were examined. The microwave radiation technique was used to desorb the gold complexes from the activated carbon. It is found to be more ef-fective as compared with other desorption methods.
The adsorption of gold-thiourea complex ions by activated carbon in solution has been studied. The adsorption rate curves and isothems were obtained and the effects of pH values of the solution and foreign ions were examined. The microwave radiation technique was used to desorb the gold complexes from the activated carbon. It is found to be more ef-fective as compared with other desorption methods.
1995, 12(2): 113-114
Abstract:
A series of hydrosiloxanes were prepared as model compounds for hydrosilylation study of 1,3-divinyl-1,1,3,3-tetramethyl-disiloxane in relation to their vinyl contents. The results show that the rate of hydrosilylation depends on the structure of the hydrosiloxane.
A series of hydrosiloxanes were prepared as model compounds for hydrosilylation study of 1,3-divinyl-1,1,3,3-tetramethyl-disiloxane in relation to their vinyl contents. The results show that the rate of hydrosilylation depends on the structure of the hydrosiloxane.
1995, 12(2): 115-116
Abstract:
The blends of polyethersulfone (PES) with polycarbonate (PC) have been pre-pared by melt mixing in a brabender. Their mechanical property and transition behavior have been characterized by tensile test, DSC and TBA. The improvement of mechanical property of PES by blending has been discussed in terms of the compatibility.
The blends of polyethersulfone (PES) with polycarbonate (PC) have been pre-pared by melt mixing in a brabender. Their mechanical property and transition behavior have been characterized by tensile test, DSC and TBA. The improvement of mechanical property of PES by blending has been discussed in terms of the compatibility.
1995, 12(2): 117-118
Abstract:
Several derivatives of chitosan were prepared and their adsorption to Cu2- and Ni2+ was studied,their structure was identified by IR.
Several derivatives of chitosan were prepared and their adsorption to Cu2- and Ni2+ was studied,their structure was identified by IR.
