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1.
由3,5-二硝基苯甲酰氯和间氨基苯甲酸合成了一种超支化AB2型单体3-(3,5-二氨基苯甲酰氨基)苯甲酸,该单体进行自缩聚反应,合成了新型超支化聚酰胺(a),将其与酰氯反应,制得7种封端超支化聚合物(b ̄h)。所得聚合物通过红外光谱(FT-IR)、核磁共振(1H-NMR)和差示扫描量热法(DSC)等进行了表征。聚合物a ̄h的特性黏度为0.063 ̄0.077dL/g,玻璃化转变温度(Tg)为54 ̄188℃。聚合物b ̄d的Tg随封端剂脂肪链增长而降低,聚合物e ̄h的Tg随封端剂极性增加而升高。封端改性后,聚酰胺的溶解性得到了不同程度的改善。 相似文献
2.
以2-氯-5-硝基三氟甲苯和1,4-环己二醇为起始原料,通过两步有机反应合成了一种新的含氟二胺单体:1,4-双[4-胺基-2-(三氟甲基)苯氧基]环己烷;并由该二胺单体和对苯二甲酸、间苯二甲酸、4,4'-二苯醚二甲酸和2,2-双(4-羧基苯基)六氟丙烷经缩聚反应制备了一系列新型聚芳酰胺,其特性黏度在0.89~1.29 dL/g之间。该类聚芳酰胺表现出了优良的溶解性能和光学性能,室温下不仅可以溶于N-甲基-吡咯烷酮、N,N-二甲基乙酰胺、N,N-二甲基甲酰胺等强极性溶剂中,还能溶于低沸点的四氢呋喃、氯仿、二氯甲烷等溶剂中;由该类聚合物溶液所制的薄膜无色透明,截断波长在335~357 nm,在400 nm后具有高透明性。此外,该聚芳酰胺还表现出了良好的热学性能,玻璃化转变温度在202~223 ℃,氮气中10 %热失重温度在330~364 ℃。 相似文献
3.
A series of novel aromatic polyamides having noncoplanar biphenylene units in the main chain and bulky naphthyl or phenyl
pendant group at 2,2′-disubstituted position were prepared from the two rigid-rod aromatic dicarboxylic acid monomers, 2,2′-diphenylbiphenyl-4,4′-dicarboxylic
acid ( 1) and 2,2′-dinaphthylbiphenyl-4,4′-dicarboxylic acid ( 2), and various aromatic diamines. These polyamides were readily soluble in many organic solvents and showed excellent thermal
stability associated with high glass-transition temperatures in the range of 229–292°C. These polymers also exhibited strong
UV–Vis absorption bands at 262–353 nm in NMP solution, and their photoluminescence spectra showed maximum bands at 440–462 nm
in the purple to blue region. The poly(amine–amide) IId derived from the diamine with triphenylamine moieties revealed excellent electrochromic contrast and coloration efficiency,
changing color from the pale yellowish neutral form to green then to the blue oxidized forms when scanning potentials positively
from 0.00 to 1.30 V.
Figure Graphical Abstract. A series of novel aromatic polyamides having noncoplanar biphenylene units in the main chain and bulky
naphthyl or phenyl pendant group at 2,2′-disubstituted position were prepared from the two dicarboxylic acids and various
aromatic diamines. These polyamides were readily soluble in many organic solvents and showed excellent thermal stability associated
with high glass-transition temperatures in the range of 229–292°C. These polymers also exhibited strong UV–Vis absorption
bands at 262–353 nm in NMP solution, and their photoluminescence spectra showed maximum bands at 440–462 nm in the purple
to blue region. The poly(amine–amide) IId derived from the diamine with triphenylamine moieties revealed excellent electrochromic contrast and coloration efficiency,
changing color from the pale yellowish neutral form to green then to the blue oxidized forms when scanning potentials positively
from 0.00 to 1.30 V. 相似文献
5.
A new aromatic dicarboxylic acid monomer 4-pyridylformylimino-N-(phenyl,2′,5′ – dicarboxylic acid) (PPDC) containing pyridine and azomethine units was synthesized through a simple one-step condensation reaction between 2-aminoterephthalic acid and 4-pyridinecarboxaldehyde. A series of new polyamides was prepared through the direct one-pot phosphorylation polycondensation of PPDC with simple aromatic commercial diamines and diamines bearing phenylthiourea groups. The polyamides were characterized by FT-IR, 1H-NMR, and 13C-NMR spectroscopy. Thermal stability of the polymers was evaluated using thermogravimetric analysis. The polyamides with inherent viscosities in the range of 0.30–0.51 dL/g showed an outstanding solubility in various solvents such as 1-methyl-2-pyrrolidone (NMP), dimethly sulfoxide (DMSO), N,N-dimethylformamide (DMF), N,N-dimetylacetamide (DMAc), and pyridine. The cured polyamides displayed significantly higher thermal stability than the uncured polyamides. The conductivity of the polyamides, when blended with 20% by weight of doped polyanilines, was in the range 3.09–4.21 × 10 ?3 S cm ?1. 相似文献
6.
This research was primarily focused on investigating the possibility of the production of novel organo-soluble polyamides with coordination metal complex units in the main chain. Using a copper(II) coordination complex as a monomer, a novel Cu(II)-containing polyamide was synthesized by polycondensation with m-phenylenediamine. The obtained polyamide with Cu(II) ions in the main chain had an inherent viscosity of 0.20 dL/g, which indicated that it was a low molecular weight polymer. Then the p-phthalic acid monomer was introduced to the above synthesis system to create a Cu(II)-containing co-polyamide with a higher molecular weight. The subsequent addition of p-phthalic acid resulted in the formation of a series of co-polyamides with different contents of the Cu-complex in the main chain, which had higher inherent viscosity. The structures of the Cu(II)-containing polymers were characterized by ICP and 1H-NMR. The prepared co-polyamides had increased solubility in organic solvents. It also revealed that the UV absorption properties of co-polyamides were enhanced significantly by the incorporation of Cu(II) ions into the polymer chain. 相似文献
7.
综述了用于聚酰胺(PA)和耐高温聚酰胺(HWA)的三大阻燃系统,即聚合型或低聚型溴系阻燃系统、无卤阻燃系统及纳米无机填料(纳米粘土和碳纳米管)的近况,系统地论述了它们的性能及特点,并介绍了它们的生产厂家及商品牌号。 相似文献
8.
A new quinoxaline moiety containing aromatic diamine; 2,3-bis[4-(4-aminophenoxy)phenyl]quinoxaline (APQ) was synthesized starting from 4-methoxybenzaldehyde and was characterized by IR, 1H, 13C NMR and Mass spectrometry. Five new polyamides were synthesized by polycondensation of various aliphatic diacid / aromatic diacids namely, azelaic acid, bis(4-carboxyphenyl)dimethylsilane, 4,4′-oxybis(benzoicacid), isophthalic acid and terephthalic acid with APQ by Yamazaki’s phosphorylation method using triphenyl phosphite as condensing agent. The polyamides were characterized by IR spectroscopy, solubility tests, inherent viscosity, X-ray diffraction technique, differential scanning colorimetry and thermogravimetric analysis. The polyamides had inherent viscosities in the range 0.39–0.45 dL/g in N, N-dimethylacetamide at 30?±?0.1?°C. The polyamides were soluble in polar aprotic solvents such as N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone. X-Ray diffraction studies showed that polyamides were amorphous in nature. The polyamides showed glass transition temperatures in the range 104–205?°C, according to differential scanning calorimetry. Thermogravimetric analysis exhibited initial decomposition temperatures above 348?°C; indicating that these polyamides possessed excellent thermal stability. 相似文献
9.
The sulfonation of polyamides (Nylons-3,6,11 and 6,6) was investigated using fuming sulfuric acid and solutions of SO 3 in CCl 4. The sulfonated polymers were soluble in water and insoluble in ethanol. Acid hydrolysis of the polymers and quantitative determination of the amino acids in the hydrolysate showed the presence of α-sulfo amino acids. This showed that sulfonation in the polymer occurred in the active α-position of the amide group. 相似文献
11.
Efforts have been devoted to synthesize and characterize processable polymers with desired properties. Herein, four different series of aromatic and aliphatic terpolyamides were prepared via solution phase polycondensation of 4,4′-oxydianiline and hexamethylenediamine (HMDA) with various diacids chlorides (isophthalyol dichloride, terepthalyol dichloride, 1, 1′-ferrocene dicarboxylic acid chloride and trans-azobenzene-4, 4′-dicarbonyl chloride). The structural, morphological and physico-chemical nature of as prepared polymers was explored by Fourier-transform infrared spectroscopy, scanning electron microscopy, thermal analysis (TGA and DSC), and wide-angle x-ray diffraction. Moreover, an aliphatic diamine was incorporated in varying concentration as a flexible methylene spacer and the effect of its concentration on the properties of polyamides was also studied. Changes in various physico-chemical properties such as solubility, inherent viscosity, surface morphology and flame retarding behaviour were investigated. Marked difference in morphology and solubility was observed with the change in the ratio of segments in the chain. Inherent viscosities of polymers ranged from 1.8052–1.6274 dl/g indicating reasonably moderate molecular weights. Interestingly, ferrocene based aromatic polymers were more thermally stable (Tg 260 °C, Ti 310 °C, Th 525 °C, Tf 720 °C, for PF0), and also found to exhibit best flame retarding behavior (limiting oxygen index value for PF0is LOI 33.15%). 相似文献
12.
A series of polyamide and copolyamide resins were prepared from carboxystearic acid or methyl carboxystearate, with ethylenediamine, hexamethylenediamine, adipic acid, or caprolactam as coreactants. None of the product formulations appeared suitable for use in hot melt adhesives. More promising were the liquid, reactive polyamides made from carboxystearic acid and polyamines. These products gave excellent adhesion value in scouting tests when used as one component in 2-component epoxy adhesives and coatings. In other applications, C-19 polyamides had enhanced solubility and low melting characteristics to make them attractive as modifiers. 相似文献
14.
Summary The preparation and properties of various polyamides, copolyamides, and modified polyamides, of polymeric fat acids have been
described. These polymers are of interest because of their unusual properties and because of the unsaturation and relatively
high molecular weight of the polybasic acids involved. Despite the presence of tribasic acids in polymeric fat acids, ungelled
polymers having molecular weights of 3,000 to 5,000 are obtainable. A brief discussion has been given concerning the application
of theoretical principles of polymerization to the preparation of these polymers. Possible industrial uses for the polyamides
are indicated.
This is one of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration,
U. S. Department of Agriculture. 相似文献
16.
不同种类聚酰胺的结构和性能不同,为了便于生产,需对聚酰胺的种类进行鉴别.讨论了用红外光谱法鉴别不同种类聚酰胺,包括:试样制备、谱图分析、结论与建议.谱图分析概述了不同种类聚酰胺红外吸收光谱的共同特征,详细分析了不同种类聚酰胺红外吸收光谱的区别,包括尼龙6和尼龙66,尼龙11和尼龙12,尼龙610、尼龙612和尼龙1010,尼龙6T和尼龙9T共4组红外光谱图特征区别峰. 相似文献
18.
An attempt is made to establish the most proper initial structure for the obtaining of highly drawn (at room temperature) nylons and polyesters. It is found that neither the completely crystalline structure nor the fully amorphous one but a low-crystallinity, very imperfect structure (with a large number of small crystallites) is the most suitable one. Through ultraquenching of nylon 6 and PBT melts, and storage at ambient conditions, draw ratios of 7 and 8, respectively, are achieved. Subsequent annealing results in the obtaining of doubly higher values of the elasticity modulus and tensile stress. By means of WAXS, SAXS, IR spectroscopy, and DSC measurements the obtained structure is characterized. The highly drawn and annealed samples show a strongly reduced concentration of chain folds and a lack of long spacing. 相似文献
19.
Three new polyamides containing ferrocene units in the main chain were synthesized via low temperature polycondensation route,
reacting 1,1′-ferrocenedicarboxylic acid chloride with three different types of aromatic diamines. The products were characterized
by their solubilities, elemental analysis, FTIR spectral analysis, differential scanning calorimetry, thermogravimetry and
viscosity measurements. The glass transition temperatures of the polymers were found by DSC curves and the activation energies
of pyrolysis were estimated from TG curves applying Horowitz and Metzger method. Among these, polyamide P-1 (prepared from
4-(4-aminophenyloxy)phenyl-4-aminobenzamide) was found soluble in some of the organic solvents at room temperature but has
poor thermal stability. Polyamide P-2 (prepared from 1,2-di( para-aminophenyloxy)ethylene) was soluble on heating and is thermally stable. However, all of these were also miscible with concentrated
H 2SO 4 forming red coloured solutions.
Graphical Abstract Ferrocenedicarbonyl chloride was reacted with three different types of aromatic diamines via solution polycondensation to
get three new polyamides. Two of which were soluble in some organic solvents. The resulting polymers were characterized by
their solubilities, viscosity measurements, elemental analysis, FTIR spectroscopy, differential scanning calorimetric and
thermogravimetric studies.
相似文献
20.
介绍了聚酰胺用各种阻燃剂(卤素阻燃剂、无卤阻燃剂和阻燃协效剂)的主要品种、特点、开发现状。指出了聚酰胺用阻燃剂的发展方向为提高热稳定性、流动性和分散性。 相似文献
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