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1.
A series of new amphoteric surfactants, having a quaternary ammonium group and a phosphoric acid group, 2-(N-alkyl-N,N-dimethylammonio)ethyl hydrogen phosphates (alkyl: dodecyl, tetradecyl, hexadecyl), were prepared by introducing a phosphoric acid group into N-alkyl-N,N-dimethyl-(N-2-hydroxyethyl) ammoniumiodide, followed by neutralization with sodium hydroxide and removal of inorganic salts. By the evaluation of the physicochemical properties, it was found that the phosphobetaines behave like “nonionic” surfactant in the zwitterionic region, having very small CMC values in comparison with sodium 2-(N-alkyl-N-methylamino)ethyl hydrogen phosphates. Additionally, similar trends were also observed in the experiments from the point of the effect of electrolyte and temperature on CMC, respectively. It should be considered that the hydrophobicity of the surfactant molecule is increased by the electronic interaction between the quaternary ammonium group and a phosphoric acid group. On the other hand, the phosphobetaines gave the smaller values of the occupied area per molecule at the air/water interface than sodium 2-(N-alkyl-N-methylamino)ethyl hydrogen phosphates. Therefore, it is clear that the phosphobetaines have higher surface-active properties than the amphoteric surfactants.  相似文献   

2.
A series of new phosphate type of amphoterics having a 2-hydroxyalkyl group as a hydrocarbon chain, 2-(N-2-hydroxyalkyl-N,N-dimethylammonio)ethyl hydrogen phosphates (alkyl[R]:dodecyl, tetradecyl, hexadecyl), was synthesized and their physicochemical properties—isoelectric point, critical micelle concentration (CMCs), occupied area/molecule at interface and the change of free energy of micellization—and antimicrobial properties were investigated in comparison with those of sodium 2-(N-alkyl-N-methylamino)ethyl hydrogen phosphates. It was found that the CMCs and the occupied areas were observed to decrease due to a phosphobetaine moiety and a 2-hydroxyethyl group. Solution properties of the binary system of SDS/2-(N-2-hydroxytetradecyl-N,N-dimethylammonio)ethyl hydrogen phosphate in aqueous solutions were studied in terms of surface tension and pH value. On the other hand, it was observed that the Minimum inhibitory concentration (MICs) of 2-(N-2-hydroxyhexadecyl-N,N-dimethylammonio)ethyl hydrogen phosphate against fungi were smaller than those of chlorhexidine digluconate.  相似文献   

3.
戴燕  吕春绪  李斌栋  谭卫红 《精细化工》2013,30(2):221-224,228
以2-(4-氨基苯基)六氟异丙醇(Ⅰ)为原料,经重氮化、水解制得2-(4-羟基苯基)六氟异丙醇(Ⅱ),产物结构经EA、IR、1HNMR和MS确认;同时,对影响反应的主要因素进行了系统考察。结果表明,在重氮化反应温度为-2~2℃、w(H2SO4)=w(NaNO2)=30%、n(H2SO4)∶n(NaNO2)∶n(Ⅰ)=4.1∶1.1∶1.0及水解反应温度110℃、w(H2SO4)=50%、n(H2SO4)/n(Ⅰ)=11.0、水解时间2 h的优化条件下,目标物的平均收率高达91%。  相似文献   

4.
A series of new amphoteric surfactants having a phosphoric acid group, a tertiary amino group and a 2-hydroxyalkyl group, sodium 2-(N-2-hydroxyalkyl-N-methyl-amino)ethyl hydrogen phosphates (alkyl: n-tetradecyl, n-hexadecyl, n-octadecyl), were prepared by an addition reaction of 1,2-epoxyalkanes to N-methylaminoethanol, followed by the introduction of a phosphoric acid group and neutralization with sodium hydroxide. The structures of these compounds were confirmed by spectroscopy and elemental analysis. The solubility in solvents, Krafft point, surface tension, critical micelle concentration (CMC), occupation area of the molecule at the surface of aqueous solutions and foaming power were measured. It was shown that a 2-hydroxyethyl group in a long alkyl chain seemed to behave as a hydrophobic part.  相似文献   

5.
胡玲  胡波  杨旭  贾卫斌 《山东化工》2010,39(7):22-24
(Z)-2-(呋喃-2-基)-2-甲氧亚胺基乙酸是一种重要的医药中间体,主要用于合成头孢菌素-头孢呋辛(头孢呋辛钠或头孢呋辛酯)。按照不同的合成原料、试剂和反应路线对(Z)-2-(呋喃-2-基)-2-甲氧亚胺基乙酸的合成方法进展进行了综述。  相似文献   

6.
Samples of poly[1–(trimethylsilyl)–1–propyne] were kept for about 4 years in ambient conditions. The permeability and diffusion coefficients were examined and found to be decreased by 1–2 orders of magnitude. To ascertain the nature of the changes underwent during long-term storage of this polymer, several physicochemical methods were applied: positron annihilation, wide-angle X-ray diffraction, spin probe, and density evaluation. These studies indicated that a decrease of free volume and more close chain packing took place during the aging process. IR spectroscopy and 13C-NMR showed that oxygen-containing products appeared in the polymer after long-term storage. This should result in a certain decrease in the rigidity of the backbone chains and more intensive interchain in-teractions, and, hence, in a decrease in the free volume of the aged polymer. © 1993 John Wiley & Sons, Inc.  相似文献   

7.
8.
以邻氨基对硝基苯酚和对硝基苯甲酰氯为原料进行酰胺化反应,再用多聚磷酸进行环化反应,得到中间体5-硝基-2-(4-硝基苯)苯并噁唑(NNB);中间体在77~80℃,压力为2.0~2.5MPa,Raney-Ni作催化剂条件下高压催化加氢合成了5-氨基-2-(4-氨基苯)苯并噁唑,纯度为99.8%,总收率为81.1%。通过熔点、MS、元素分析对产品进行了结构表征。  相似文献   

9.
An oxetane-derived monomer, 3-acryloyloxy-methyl-3′-methyloxetane (AMO) was prepared from the reaction of 3-hydromethyl-3-methyloxetane with acryloyl chloride. The cationic ring-opening copolymerization of AMO with another oxetane-derived monomer, 3-(2-(2-(2-methoxyethylenoxy)ethylenoxy)ethylenoxy)-3′-methyloxetane (MEMO) was conducted in CH2Cl2 solution using BF3 · OEt2/1,4-butanediol as a co-initiator. The resulting copolymers were characterized by FTIR, 1H NMR and Gel Permeation Chromatography (GPC) analyses, and it was found that the enchained ratio of AMO in the copolymers is far lower than its feed ratio. They were crosslinked in situ via the radical polymerization of the vinyl group initiated by BPO after doping with lithium trifluoromethanesulfonimide (LiTFSI) to give rise to tough polymeric electrolyte films. The ionic conductivity was measured at varying content of AMO and different concentration of lithium salt LiTFSI by AC impedance, and a maximum ion conductivity of 1.44 × 10−5 S/cm at 30°C or 1.25 × 10−4 S/cm at 80°C was attained in the sample PAM 33 at the mole ratio of O: Li = 20. The DSC results indicated that T g decreases with the increase of the proportion of AMO in the copolymer, well consistent with the ion conductivity trend. The TGA (thermogravimetric analysis) measurement revealed that this kind of copolymer electrolytes is more thermostable than their liquid counterparts. __________ Translated from Transactions of Beijing Institute of Technology, 2006, 26(12): 1098–1103 [译自: 北京理工大学学报]  相似文献   

10.
Homo- and copolymerizations of 1,5-hexadiene with ethene and styrene using halfsandwich metallocene catalyst Me2Si(Me4Cp)(N-tert.-butyl)TiCl2/MAO (Cp = cyclopentadienyl, Me = methyl, MAO = methylalumoxane) were investigated. According to 13C-NMR spectroscopic microstructure analysis, cyclopolymerization of 1,5-hexadiene afforded randomly distributed cis- and trans-cyclopentane rings in the homo- and copolymer backbone. 1,5-hexadiene incorporation reached 52 mol-%. The ratio of vinyl side chains to cyclopentane rings was controlled by 1,5-hexadiene concentration, where low 1,5-hexadiene concentration promoted cyclopolymerization. Copolymer glass transition temperatures increased with increasing content of cyclic units in the backbone. Styrene was used successfully as termonomer in ethene/1,5-hexadiene polymerization, resulting in a semicrystalline terpolymer with cyclic and styrenic units in the polymer backbone. Received: 5 September 1996/Accepted: 11 November 1996  相似文献   

11.
Conclusions One-, two-, and three-stage methods of preparing structurally-dyed aromatic polyamides with chromophoric fragments in the chain have been investigated.It has been shown that the molecular weight of the polymers obtained and the proportion of chromophores bound into their chain is determined by the reactivity of the starting diaminoanthraquinones.It has been found that the introduction of anthraquinone units into the poly-m-phenylene isophthalamide chain has little effect on the structure or basic physicochemical properties of the polyamide, but gives the polymer a uniform and regular coloration.Structural dyeing of poly-m-phenylene isophthalamide with fragments of 1,5-DAAQ or 4,8-DADHAQ increases the resistance of the polyamide fibres to UV irradiation.The authors express their thanks to Yu. Ya. Shavarin and N. M. Bol'bit for performance of the fibre irradiation, and also to B. A. Tsaplin for thermomechanical testing of the fibres.L. Ya. Karpov NIFKhI, Moscow. VNIISV, Tver'. Translated from Khimicheskie Volokna, No. 2, pp. 24–27, March–April, 1992.  相似文献   

12.
Yu Nagase  Koji Ikeda  Yoshiro Sekine 《Polymer》1982,23(11):1646-1652
Tetramethyl-p-silphenylenesiloxanealkenylmethylsiloxane (TMPS/AMS) copolymers were snyhtesized from p-bis-dimethylhydroxysilylbenzene and a series of alkenylmethyldichlorosilanes as the starting materials. The alkenyl groups of the copolymers were vinyl, allyl, 2-(3-cyclohexenyl)ethyl, methacryloxypropyl and 3-bicycloheptenyl groups. The composition ranged from TMPS/AMS mole% ratio of 928 to 8317 and the molecular weights were in the range 104 to 105. These copolymers were confirmed to have two compositions, one a certain length of TMPS segment and the other an AMS monomer unit, and that they could form films on the basis of the crystallization character of the TMPS segment. The melting temperatures of these copolymers decreased as the TMPS mole content decreased and as the alkenyl group contents were increased. The epoxidation reactions of these copolymers with m-chloroperbenzoic acid were carried out and the proportions of conversions of the alkenyl groups into epoxy groups varied depending upon the types of alkenyl groups involved. Cyclic olefin groups such as the 2-(3-cyclohexenyl)ethyl or the 3-bicycloheptenyl group were more easily epoxidized than the vinyl or allyl groups. The TMPS/dimethylsiloxane (DMS) graft copolymer could also be synthesized by the reaction of TMPS/vinylmethylsiloxane copolymer with dimethylhydrosilyl-terminated DMS oligomer in the presence of chloroplatinic acid acting as the catalyst.  相似文献   

13.
《应用化工》2013,(11):2130-2131
以(S)-(2-甲基丁基)苯为原料,经碘代和Suzuki偶联四步反应,合成了手性液晶(S)-4-(2-甲基丁基)-4'-(4-丙基环己基)-2-氟联苯,总收率11.4%,纯度99.2%,并采用IR、MS、1H NMR及元素分析对其结构进行了表征。结合差示扫描量热仪(DSC)和偏光显微镜(POM)研究了目标化合物的介晶性,并采用Cano’s wedge法测定了目标化合物的扭曲力。  相似文献   

14.
韩亮  李正名  张云  杨娜  郭维明 《农药》2005,44(4):165-166,173
烷氧基磷酰二氯与取代苯酚、N-硬脂酰乙醇胺反应制备得到了6个新的标题化合物,其结构用核磁、元素分析进行了表征,并对它们的植物生长调节和杀菌活性进行了测定。  相似文献   

15.
Nine dialkyl trichloromethylphosphonates (TCMPs) were synthesized by the Arbusov reaction from the corresponding trialkyl phosphite and carbon tetrachloride. Some characteristics of these compounds were studied. The alkyl groups contained from 2 to 18 even carbon atoms. The reaction of triethyl phosphite and carbon tetrachloride was completed in about 4 hr under an indoor natural light. However, in the preparation of the lower dialkyl TCMPs the mixture of trialkyl phosphite and carbon tetrachloride was refluxed for 8 hr. With alkyl groups higher than decyl, a reaction time of 8 hr was insufficient. Utilization of these dialkyl TCMPs was discussed. These compounds were shown to be effective chelating, antistatic and flame resistant additives in a formulation of polyvinyl chloride. Moreover, they were found to be very excellent extreme pressure additives for lubricating oil; especially the dibutyl TCMP which was extremely effective at concentrations as low as 0.25%. Presented at the Japan Oil Chemists’ Society Meeting in Tokyo, October 1968.  相似文献   

16.
The effects of cefoperazone sodium (CS), a pharmaceutical compound, on the critical micelle concentration (CMC) of surfactants with different charges [cetyl trimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), and Triton X-100], the cloud point of Triton X-100, and the Krafft temperatures of SDS and CTAB were studied. The interaction of CS with differently charged surfactants was determined by ultraviolet and fluorescence spectrophotometry. The results show that with increasing CS concentration, the Krafft temperature increases and the CMC decreases in the SDS/H2O system, whereas the opposite results are obtained in the CTAB/H2O system. Both the cloud point and the CMC of Triton X-100 increase with the addition of CS. The above results are attributed to the different micellar interactions between CS and surfactants with different charges.  相似文献   

17.
The objective of this study was to analyse how macromolecular structure of polylactides influences their properties and degradation rate. To achieve this, novel 2- and 4-armed PDLLA and PLLA (noted as 2b and 4b) were synthesized by ring-opening method. 1,4-butanediol and pentaerythritol were used as initiators and stannous octoate was used as catalyst. The obtained polymers were investigated in terms of molecular weight by size exclusion chromatography, thermal properties by differential scanning calorimetry and thermogravimetry, and hydrophilicity by the contact angle measurements. The in vitro degradation test was carried out in PBS solution at 37 °C by means of the mass loss, water uptake, molecular weight and thermal properties changes. The branched polylactides including 2bPDLLA, 4bPDLLA, 2bPLLA and 4bPLLA were successfully synthesized and the average molecular weights were around 40-45 kDa. The numbers of arms in each polymer just slightly influenced the thermal properties and the contact angle. The crystallinity of 4bPLLA was 23 %, whereas for 2bPLLA it was 41 %. The degradation rates of both 2b and 4bPLLA were similar and the degradation process was similar only during first 7 weeks. After this period, the degradation rate of 4bPDLLA increased. Consequently, thermal properties and degradation profiles of the branched polymers would depend on plural factors, such as chain length and crystallinity in branched structure.  相似文献   

18.
The micelle-forming monomers of sodium 6-acrylamidocaproate (Na 6-AAC), sodium 11-acrylamidoundecanoate (Na 11-AAU), sodium 11-(N-methylacrylamido) undecanoate (Na 11-MAAU), and sodium 11-(N-ethylacrylamido) undecanoate (Na 11-EAAU) have been synthesized and polymerized. Except poly(Na 6-AAC), the molecular weights of the other three poly(sodium acrylamidoalkanoate) s were over 106. They behave as strong anionic polyelectrolytes in aqueous solutions. Their solution properties, such as viscosity, charge density, and radius of gyration, were investigated. The performance of these anionic polyelectrolytes as coagulant aids in water treatment were assessed by jar test. Poly(Na 6-AAC) and poly (Na 11-AAU) were superior to poly (Na 11-MAAU) and poly (Na 11-EAAU) in terms of flocs settling. All these four anionic polyelectrolytes tested in water treatment are as effective as a commercially available cationic polyamine organic coagulant (Hyperfloc CP 753).  相似文献   

19.
A (sulfonylbisphenoxy)-containing cyclotriphosphazene polymer system has been prepared by polycondensation of (phenoxy)chlorocyclotriphosphazene and 4,4-sulfonylbisphenol. The syntheses by polycondensation using sodium salt of 4,4-sulfonylbisphenol and by interfacial polycondensation were carried out for comparison. The characterization, thermal stability, and fire resistance of the synthesized polymers were studied. Thermogravimetric analysis showed that the polymers prepared were stable to above 400°C in nitrogen and exhibited high char contents at elevated temperature. The result indicated that the presence of a sulfonyl group was helpful for enhancing thermal stability and the presence of a phosphphazene ring was the cause of the high char residue at elevated temperature.  相似文献   

20.
Aromatic bismaleimides (BMIs) were prepared by the condensation of malefic anhydride with multiring diamines containing ether bridges. The thermal behavior of the bismaleimides was investigated by differential scanning calorimetry (DSC). Thermogravimetric analysis (TGA) and thermomechanical analysis (TMA) were utilized to characterize the thermal properties of the cured resins. The effect of the structures of bismaleimides on their thermal behavior and the thermal properties of the cured resins is discussed. Increasing molecular weight between reactive endgroups lowered melting points of BMIs, leading to a large temperature range between their melting point and the initial polymerization temperature. The introduction of ether bonds together with other flexible partners to bismaleimide resins decreased the glass transition temperatures or softening temperatures and the brittleness of the cured bismaleimide resins without extreme loss of their thermal stability. The cured bismaleimides were stable up to 450°C in both air and nitrogen.  相似文献   

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