双胺醚制备中二乙烯三胺和双胺醚的气相色谱分析

双胺醚制备中二乙烯三胺和双胺醚的气相色谱分析张惠良，施耀增，杜争鸣，吕槊贤，阮劲松（南京大学化学系，南京，２１０００８）关键词：双胺醚；二乙烯三胺；气相色谱分析ＣＨ＿３＼双胺醚［Ｎ—ＣＨ＿２—ＣＨ＿２］，亦称双（Ｎ，Ｎ－二甲胺基乙基）醚，可采用二乙烯...     

The Synthesis and the Cationic Fluorescence Role of Glycols with Aromatic End Groups, Part III

Some novel bis-(substituted-phenoxy) ended glycols were synthesised usinghydroxy aromatics of vanillin, o-vanillin, iso-vanillin and 4-hydroxy coumarin which reacted with bis-dihalides of polyglycols in the presence ofDMSO/alkali carbonate. The novel podands, Ar-(CH₂CH₂O)_m-Ar,(m = 1–4), were identified with IR, ¹H-NMR, ¹³C-NMR and mass spectrometry. The various (formyl-methoxy)phenyl and 4-oxycoumarin derivatives of glycols were studied to estimate the cation binding selectivity of SCN^- salts ofLi⁺, Na⁺, K⁺ and Zn²⁺ cations in acetonitrile using steady statefluorescence spectroscopy. The relevant structures of podands have shown goodselectivity depending on the cation and the glycollength, although the chromophoreend groups have no specific contribution on binding.     

Speeds of sound and isentropic compressibilities of (2-ethoxyethanol + ethylene glycol, diethylene glycol, triethylene glycol, and tetraethylene glycol) binary mixtures at 298.15 K

The speed of sound (u) has been obtained at a frequency of 8.3 MHz in {CH₃CH₂OCH₂CH₂OH + HOCH₂CH₂(OCH₂CH₂)_nOH}for n = 0, 1, 2, and 3 over the whole composition range of studied binary liquid mixtures, at T = 298.15 K. The speed of sound values were combined with those of our previous results for densities and viscosities to obtain isentropic compressibility (κ_s), free volume (V_f), and intermolecular free length (L_f). From all these data excess isentropic compressibility (κ_s^E), excess free volume (V_f^E) and excess intermolecular free length (L_f^E) as well as the deviations of the speed of sound (Δu) were obtained. The results are interpreted in terms of molecular interactions occurring in the solutions.     

聚合物对非离子十二烷基聚氧乙烯聚氧丙烯醚浊点的影响

测定了水溶性高分子聚乙二醇（PEG1000、PEG2000、PEG6000）和聚乙烯吡咯烷酮（PVP－K30、PVP－K90）对三种非离子表面活性剂十二烷基聚氧乙烯聚氧丙烯醚C12H25O（EO ）m(PO)nH(LS36,m=3,n=6,LS45,m=4,n=5;LS54,m=5,n=4)浊点的影响。结果表明,聚乙二醇（PEG） 可使三种表面活性剂水溶液浊点降低;而聚乙烯吡咯烷酮（PVP）随其浓度增加,表面活性剂溶液浊点先升高然后又下降;浊点下降程度与聚合物浓度和分子量有关。     

Microemulsion polymerization of styrene stabilized by sodium dodecyl sulfate and diethylene glycol monoalkyl ether

The effects of the cosurfactants diethylene glycol monoalkyl ether [C _i H_{2 i +1}O(CH₂CH₂O) _j OH (C _i E _j ; i=4, 6 and j=1, 2)] on the formation of an oil-in-water styrene (ST) microemulsion and the subsequent free radical polymerization were studied. For comparison, the data for the C _i H_{2 i +1}OH (C _i OH; i=4, 6) systems obtained from the literature were also included in this work. Sodium dodecyl sulfate was used as the surfactant. The pseudo three-component phase diagram (macroemulsion, microemulsion and lamellar gel phases) was constructed for each cosurfactant. The primary parameters selected for the polymerization study are the concentrations of cosurfactant and styrene. The number of latex particles nucleated is much smaller than that of the microemulsion droplets initially present in the reaction system. Limited flocculation of the latex particles occurs to some extent during polymerization. Among the cosurfactants investigated, the C₄OH-containing polymerization system is the least stable. By contrast, the diethylene glycol monoalkyl ether group of C _i E _j tends to enhance the latex stability. C _i E _j is more effective in stabilizing the ST microemulsion and the subsequent polymerization in comparison with the C _i OH counterpart. Received: 24 December 1999 Accepted: 9 February 2000     

Apparent Specific Polarization and Dipole Moment of Some Poly(oxyethylene) Glycols in 1,4-Dioxane and Benzene Solutions at 298.15 K

Summary. The electrical permittivity of 1,4-dioxane and benzene solutions of some poly(oxyethylene) glycols up to the average molecular weight of 1590 were measured at 298.15 K. From the experimental data the limiting apparent specific polarization and partial molar polarization were calculated. The electrical dipole moment of the investigated solutes was estimated according to the Debye, Onsager, and Kirkwood theoretical approaches. The calculated dipole moments increase linearly with the square root of the number of monomeric units. The group dipole moment of the polar monomeric unit was calculated from the corresponding limiting partial molar volume, the refraction and polarization of the solute. The factor g, which takes into account the degree of flexibility of the chain, was estimated and found to be greater than 0.92, which means that the lower members of the poly(oxyethylene) glycols possess almost free rotation within the chain backbone of polymer.     

A means of analysing glycols,especially ethylene glycol and diethylene glycol,by a method used for the determination of carbohydrates in alcoholic beverages

Summary This paper describes the separation of carbohydrates/glycerol/ethylene glycol/diethylene glycol in alcoholic liquids by TLC. An in situ reaction already proven in carbohydrate analysis is used for the detection among other things, of diethylene glycol in low, unpermitted concentrations and is compared with vanadium pentoxide derivatisation also described in the literature. Only the vanadium pentoxide reaction yields satisfactory results for diethylene glycol. The information capacity of HPTLC chromatograms is also demonstrated by the simultaneous analysis of 19 samples. Chromatogram filing is an important consideration, since the lifespans of chromatograms derivatised by the two methods vary considerably. Plates or sheets treated with dichlorofluorescein can still be evaluated over a period of years, whereas plates treated with vanadium pentoxide are unusable after only a few weeks. An advantage of the latter procedure, however, is the amenability of the chromatograms to normal photocopying.     

Thermodynamic Properties of CTAB in Aqueous Solutions of Neutral Polymers at 25°C

Interactions of polyethylene glycols (PEGs) and polypropylene glycols (PPOs) in aqueous solutions of hexadecyltrimethylammonium bromide (CTAB) were investigated through thermodynamic properties at 25°C. The densities and heat capacities of the solutions were measured with a vibrating tube densimeter and a Picker flow microcalorimeter, respectively. The variations in the apparent molar volumes and heat capacities of both solutes, calculated from the densities and heat capacities of the solutions, are unusually large in the vicinity of the CMC, reflecting the existence of very strong interactions between CTAB and PPOs. With the more hydrophilic polymers, PEGs, the apparent properties of CTAB are less affected by the presence of the polymer, indicating that PEGs interact only weakly with CTAB. This revised version was published online in August 2006 with corrections to the Cover Date.     

Use of carbowax 20M coated porapak Q for the gas chromatographic analysis of the products obtained by the ammoxidation of ethylene oxide

Summary GC separation of pure ethanolamines as well as mixtures with ethylene glycols, obtained from a real technological process is achived using Porapak Q coated with 15% Carbowax 20M. Symmetrical peaks, satisfactory resolution, and reasonable analysis times are obtained. The proposed method is suitable for a convenient, correct and express routine analysis.