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1.
Regular aliphatic/aromatic copolyoxamides were prepared from diamine-oxamides and aromatic diacid chlorides by interfacial and solution polymerization. Solution polymerization in chloroform or dimethylacetamide is preferred for the preparation of large quantities of polymers but interfacial polymerization is most conveniently carried out for the preparation of polymers with high molecular weight. Aromatic diacid chlorides used included the diacid chlorides of terephthalic acid, isophthalic acid, 2,6-pyridinedicarboxylic acid, two isomeric naphthalene dicarboxylic acids, two cyclo-hexanedicarboxylic acid isomers, as well as 1,1-cyclobutane-dicarboxylic acid. Copolymers of diamine-oxamides with mixtures of acid chlorides of isophthalic and pyridine dicarboxylic acid and isophthalic acid/tetrachloroterephthalic acid have also been prepared. Most polymers are film-forming and are soluble in concentrated sulfuric acid, trifluoroacetic acid, and dimethylacetamide (containing several per cent LiCl). A number of these polymers gave dense or asymmetric membranes, particularly the polymers from ethylene diamine as the aliphatic diamine, particularly poly(iminoethyleneimino-oxalyliminoethyleneiminoisophthaloyl) (p-222I). Diamine oxamides with more than two amide groups in the molecules have been prepared, and in one case polymers with aromatic diacid chlorides have been prepared by interfacial polymerization. All regular aliphatic/aromatic copolyoxamides are high-melting and generally decompose above 350°C without melting. They can, however, be fabricated from solution into brittle fibers or into desalination membranes.  相似文献   

2.
Ternary copolyamides were obtained either by anionic copolym-erization of ?-caprolactam, ω-capryllactam, and ω-laurinlactam or by cocondensation of AH-salt with e-caprolactam and ω-laurinlactam. These copolyamides contain nine different amide groups which can be identified by their CO-signals in the 90.5 MHz 13C-NMR spectra. From the intensities of the CO signals, the ratio of monomer units in the copolymers and hence the reactivity of the monomers can be estimated. Furthermore, the average length of the homogeneous blocks can be calculated.  相似文献   

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4.

A series of novel aromatic copolyamides were synthesized by the direct polycondensation of 2‐(4‐carboxyphenyl)‐4‐[4‐(4‐carboxyphenoxyl)phenyl]‐phthalazinone (1), terephthalic acid (TPA), and four commercial diamines. The inherent viscosities of the polyamides were between 0.79~1.56 dL/g. Introduction of the non‐coplanar phthalazinone segments into the main chains remarkably decreased the crystallinity and improved the solubility of the copolyamides. When the percentage of 1 in the diacid monomers was above 50%, the copolymers were soluble in aprotic polar solvents, such as N‐methyl‐pyrrolidinone and N,N‐dimethylacetamide. The copolyamides showed high thermal properties associated with the glass transition temperatures in the range of 276~337°C and 10% wt loss temperatures in nitrogen over 496°C. Some polymer films cast from NMP solution had tensile strengths up to 123.4 MPa, initial moduli up to 2.10 GPa, and elongation at break values up to 9.6%.  相似文献   

5.
Thermostable polymers and, more particularly, thermostable fibers and films are becoming more and more important as the demands of space-age technology increase. In the preparation of thermostable fibers having good tensile strengths and practical utility the processibility of the polymer is of great importance. Aromatic polyamides meet the two most important requirements: a high degree of thermal stability and an ease of preparation as viscous solutions that can be spun into fibers or cast into films.  相似文献   

6.
Based on the Hammett equation, a general method is established to relate the polycondensation monomer reactivity with both the monomer structural parameters and the properties of the solvent used for the non‐equilibrium ternary copolycondensation to give copolyamides. Linear plots of the logarithm of the monomer reactivity ratio, log r, versus structure parameter ΔpK could be represented by the equation log r = ρΔpK.

Relationship between log r and ΔpK using THF as the solvent.  相似文献   


7.
Abstract

The atmospheric transport of organic pollutants over long distances and their effect on the biological cycles of the sea are two major questions of concern in environmental chemistry. These processes are of particular importance in the Mediterranean Sea because of its semi-enclosed characteristics, which determine the accumulation of the pollutants entering into the system.

In order to get some insight into these processes a project (PHYCEMED), was developed for the evaluation of the atmospheric budget of organic and inorganic substances in the Western Mediterranean and for the investigation of the exchange mechanisms of these materials across the air/sea interface.

A high volume air sampling system including a cascade impactor was placed on board of the R/V le Suroit for collecting the acrosols along several transects parallel to the French, Spanish and North-African coasts, facing areas of different population densities and industrial activities. The cruise was realised on October 1983 and the particulate material was fractionated into the following sizes: 7.2, 3.0, 1.5, 0.96, and 0.03 μm. Quantitative and qualitative analyses of the aliphatic and the aromatic hydrocarbons present in these fractions were performed by high resolution gas chromatography and gas chromatography-mass spectrometry.

Total non-aromatic hydrocarbon concentrations are in the range 30-57 ng/m3 (10-14ng/m3 for n-alkanes). The distribution of n-alkanes indicates that most of the aerosol mass is associated with small particles < 1 μm.Polycyclic aromatic hydrocarbons are identified from phenanthrene to benzo(ghi)perylene with fluoranthene and pyrene as dominant compounds. Concentrations for individual PAH vary in the range 4.1 pg/m3 for benzo(a)anthracene up to 100 pg/m3 for fluoranthene. The evaluation of different contributions such as land plant waxes or soil sources and various anthropogenic sources is discussed from n-alkanes and PAH distribution patterns.  相似文献   

8.
Abstract

Viscosities of binary mixtures of tetrachloroethylene with hexane, heptane, cyclohexane, methylcyclohexane, toluene, chlorobenzene, bromobenzene and nitrobenzene were measured at 303.15 K. The values of ηE are negative in all the systems except in tetrachloroethylene + bromobenzene system. An inversion in sign from positive to negative is observed in the system, tetrachloroethylene + bromobenzene. The viscosity data were analysed in terms of absolute reaction rate and free volume theories of liquid viscosity. Further, Grunberg and Nissan Parameter has also been evaluated.  相似文献   

9.
A series of new polyanhydrides, [—OC(O)ArXC(O)(CH2)nC(O)—]m, where Ar was (substituted) phenylene, X was O or NH and n was 2, 3 or 4, was synthesized. Polyanhydride fluoresence was observed only for those with the number of methene groups in the repeating unit (n) being 2. Copolymers based on sebacic acids and the above chromophoric units can also emit light. The relative fluorescence intensity of poly[p‐(carboxyethylformamido)benzoic‐co‐sebacic anhydride] (P(CEFB‐SA)) and PCEFB, IP(CEFB‐SA) /IPCEFB, increases with a decrease in the fraction of SA. However, the fluorescence intensity of poly[o‐acetyl‐p‐(carboxyethylformamido)benzoic‐co‐sebacic anhydride] (P(ACEFB‐SA)) reaches a maximum when the ACEFB content is 50%.  相似文献   

10.
渗透汽化芳烃/烷烃分离膜材料   总被引:1,自引:0,他引:1  
芳烃/烷烃混合物的分离在石油化工及环保领域都具有重大意义.与传统的萃取精馏等技术相比,渗透汽化膜技术以其清洁、节能和高效的优点,应用于芳烃/烷烃混合物的分离并受到重视.本文综述了渗透汽化芳烃/烷烃分离膜的研究进展,概述了渗透汽化技术的基本原理和应用,重点介绍了用于渗透汽化芳烃/烷烃分离的聚酰亚胺、聚氨酯等高分子膜材料的结构特点和分离性能.总结了膜材料的接枝、共聚和共混,添加传质促进剂的改性方法.分析了渗透汽化芳烃,烷烃分离膜材料的研究思路,在此基础上对渗透汽化芳烃/烷烃分离膜材料的研究方向和发展前景进行了展望.  相似文献   

11.
Mono- and diesters of D-mannite with aliphatic acids and mixed diesters with aliphatic and aromatic acids were synthesized by transesterification of their methyl esters. The structures of the products are confirmed by PMR, 13 C NMR, and IR spectra  相似文献   

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14.
A number of hydrazines, hydrazides, and related compounds have been condensed with isatin and substituted isatins. The anticonvulsant activity of these compounds is reported.  相似文献   

15.
The reaction of aliphatic and aromatic aldehydes, aliphatic ketones, and cycloketones with hydrogen sulfide in anhydrous pyridine tiethylamine medium, provides a satisfactory method for preparation of alkyl, cycloalkyl, and aralkyl disulfides.  相似文献   

16.
17.
渗透汽化分离芳烃/烷烃混合体系的研究进展*   总被引:5,自引:0,他引:5  
杨立明  徐利文  郭勇 《化学进展》2001,13(4):303-309
本文对近年来应用于分离芳香烃/ 烷烃混合体系的渗透汽化(简称PV ) 膜材料, 特别是高分子材料进行了较为系统的综述, 并简要概述了渗透汽化膜分离特点、机制以及影响渗透汽化分离过程的主要因素。  相似文献   

18.
近年来分子内1,3-偶极环加成反应引起了较大的注意,它被用来合成某些杂环、多环以及结构复杂的天然产物,为了解决中间体问题,我们摸索了某些芳环醛肟(N-4-戊烯基)氮酮Nitrone的合成方法.通常,醛肟与活泼的卤代烃作用得到N-烷基化产物和O-烷基肟.某些碘代烃对光敏感,不很稳定,产率较低,我们采用溴代烃,方法简便,产率较高.表1给出某些芳环醛肟的烷基化产物,从中看出,Z型肟(1,4,7,12,17,20)主要生成N-烷基化产物,N/O比值为4.73-6.80;E型肟(10,15)主要生成O-烷基肟(11,16),N/O比值为0.14-0.15。  相似文献   

19.
《Analytical letters》2012,45(12):2093-2103
Abstract

A simple and rapid spectrofluorimetric method is described for the determination of aliphatic and aromatic amines on the basis of ammonia and aniline, respectively. Aromatic amines in samples were reacted at pH 5.5 with fluram immoblised on an Octadecylsilane Solid Phase Extraction (ODS-SPE) cartridge. The produced pyrrolinones were adsorbed on SPE and separated from the aliphatic amines. Analysis of these compounds was carried out by elution of SPE with 1 ml Tetrahydrofuran (THF) and determination of fluorescence intensity at excitation wavelength 400 nm and emission wavelength 475 nm. Aliphatic amines after passing from SPE were collected and reacted with fluram at pH 9.2, and extracted into dichloromethane at pH 3 and quantitated fluorimetrically.

Linear dynamic ranges and detection limits (LOD) were 1–20, 0.43 mg 1?1 and 1-200, 0.39 μg 1?1 for ammonia and aniline, respectively. The proposed method was successfuly applied for the evaluation of these compounds in local well waters and municipality wastewaters.  相似文献   

20.
Reactions of vanillin and vanillal with aromatic and functionally substituted aliphatic carboxylic acid chlorides in the presence of pyridine afforded the corresponding previously unknown esters.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1015–1019.Original Russian Text Copyright © 2005 by Dikusar, Kozlov.  相似文献   

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