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WHOLLY AROMATIC CHIRAL polyamides BEARING PENDANT PHTHALIMIDO AND L-ISOLEUCINE MOITIES

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Chinese Journal of Polymer Science 2010年第6期28卷 859-867页

作者： Shadpour Mallakpour Marziyeh Khani Organic Polymer Chemistry Research Laboratory Department of ChemistryIsfahan University of Technology

A potential biodegradable and optically active bulky chiral aromatic amide-imidic diacid monomer,（2S,3S）-5-（3- methyl-2-phthalimidylpentanoylarnino）isophthalic acid（7）,containing a rigid phthalimide and flexible L-isoleucine pendant group was synthesized in three steps.New aromatic polyamides including pendant phthalimido groups and flexible side spacers have been synthesized by direct polycondensation reaction of equimolar amounts of different aromatic diamines with an optically active diacid 7,using N-methyl-2-pyrrolidone（NMP） as a solvent and triphenyl phosphite/CaCl_2/pyridine as a condensing agent.These polyamides were characterized by FTIR,~1H-NMR spectroscopy,specific rotation, thermogravimetric and elemental analysis.The resulting polymers have inherent viscosities in the range of 0.21-0.45 dL/g. Amino acid existence in this backbone results in optically active polymers.Due to introduction of bulky and flexible groups in these polyamides,they show improved solubility in polar aprotic solvents such as NMP and dimethylacetamide and also good thermal stability（10%weight loss temperatures in excess of 330℃,and char yields at 600℃in nitrogen higher than 62%）.

关键词： polyamides Biodegradable Thermally stable polymers Thermogravimetric analysis Polycondensation reaction

SYNTHESIS AND CHARACTERIZATION OF ORGANOSOLUBLE polyamides FROM QUINOXALINE BASED DIAMINE

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Chinese Journal of Polymer Science 2010年第2期28卷 147-155页

作者： Hossein Mighani Mousa Ghaemy Department of Chemistry University of Golestan Department of Chemistry University of Mazandaran

Aromatic/aliphatic polyamides were synthesized from a diamine monomer, 2,3-bis-p-aminophenylquinoxaline （IV）, based on quinoxaline and various dicarboxylic acids of aliphatic, aromatic and heterocyclic. The diamine and polyamides were characterized by elemental analysis, FTIR and IH-NMR. The solubility of the polyamides was affected by the quinoxaline and heterocyclic groups in the polymer chain. They were all soluble in common organic solvents such as dimethylsulfoxide （DMSO）, N,N-dimethylformamide （DMF） and N-methylpyrolidone （NMP）. The polyamides showed inherent viscosity in the range of 0.25-0.3 dL/g in DMSO at 25℃ and good thermal stability with the char yields in the range of 65%-82% at 600℃ in nitrogen.

关键词： Quinoxaline polyamides Solubility Thermal stability

SYNTHESIS AND CHARACTERIZATION OF polyamides DERIVED FROM(4-(4-(2,6-DIPHENYLPYRIDIN-4YL)PHENOXY)PHENYL)-3,5-DIAMINOBEZAMIDE

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Chinese Journal of Polymer Science 2012年第1期30卷 82-92页

作者： Mousa Ghaemy Soheila Khajeh Faculty of Chemistry University of Mazandaran BabolsarIran

New types of polyamides containing pendent triaryl pyridine groups were successfully synthesized by direct polycondensation of a symmetry diamine,（4-（4-（2,6-diphenylpyridin-4yl）phenoxy）phenyl）-3,5-diaminobezamide（DPDAB）, and various aromatic and aliphatic dicarboxylic diacids in NMP using triphenyl phosphate（TPP） and pyridine as catalyst. The diamine and all the prepared polyamides were fully characterized by using FT-IR,~1H-NMR,UV-Vis spectroscopy, fluorimetry and elemental analysis.The inherent viscosity of polyamides ranged from 0.45 dL/g to 0.68 dL/g.All the polymers exhibited solubility in common polar aprotic solvents such as NMP,DMAc,DMF,DMSO,pyridine,HMPA,and even in less polar solvents such as THF and m-cresol at room temperature.Thermal properties of polyamides were evaluated by means of DSC,DMTA and TGA.These polymers showed glass transition temperatures（T_g） in the range of 138-210℃. Their initial decomposition temperature（T_i） varied from 265℃to 310℃under N_2.The dilute solution（0.2 g/dL） of polyamides in DMF exhibited fluorescence emission withλ_（max） in the range of 470-550 nm.

关键词： polyamides Synthesis Direct polycondensation Solubility Thermal stability

SYNTHESIS AND CHARACTERIZATION OF SCHIFF-BASE-CONTAINING polyamides

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Chinese Journal of Polymer Science 2011年第2期29卷 149-155页

作者： Mousa Ghaemy Hossein Mighani Raouf Alizadeh Department of Chemistry Mazandaran UniversityBabolsarIran

A series of new Schiff base polyamides（PAs） were synthesized by polycondensation of benzilbisthiosemicarbazone diamine（LH6） with different commercially available aliphatic and aromatic diacid chlorides. The monomer and all the PAs were characterized by FTIR,^1H-NMR,and elemental analysis.The prepared polyamides showed inherent viscosities in the range of 0.30-0.36 dL/g in DMF at 25℃,indicating their moderate molecular weight.The PAs were completely soluble in aprotic polar solvents such as dimethylformamide（DMF）,N-methylpyrolidone（NMP）, tetrachloroethane（TCE）,dimthylsulfoxide（DMSO） and also in H_2SO_4 and partially soluble in THF,acetone and chloroform at room temperature.Thermal analysis showed that these PAs were practically amorphous and exhibited 10%weight loss above 220℃.

关键词： polyamides Schiff base polymers Solubility Thermal stability

ORGANOSOLUBLE,THERMALLY STABLE polyamides CONTAINING SULFONE AND SULFIDE UNITS

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Chinese Journal of Polymer Science 2009年第6期27卷 781-787页

作者： Shahram Mehdipour-Ataei Mehdi Hatami Mohammad Hossein Mosslemin Iran Polymer and Petrochemical Institute Department of Chemistry Isfahan University of Technology Department of Chemistry Islamic Azad University

A new diamine containing sulfone,sulfide and amide groups was synthesized via a three-step reaction process. The nucleophilic substitution reaction of 4-aminothiophenol with 4-nitrobenzoyl chloride in the presence of propylene oxide (PO) afforded N-(4-mercaptophenyl)-4-nitrobenzamide(MPNB).The catalytic reduction of the nitro group in MPNB to amino group was accomplished by using Pd/C and hydrazine monohydrate to produce 4-amino-N-(4-mercapto phenyl)benzamide(AMPB).Reaction of two moles of AMPB with bis(4-c...

关键词： Polymerizations Polycondensation Nucleophilic substitution polyamides Thermal properties

Synthesis of organosoluble polyamides with bulky triaryl imidazole pendent group

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Chinese Chemical Letters 2009年第8期20卷 961-964页

作者： Mousa Ghaemy Hossein Behmadi Raouf Alizadeh Faculty of Chemistry Mazandaran UniversityBabolsar 47416-1467 Iran

New unsymmetrical diamine monomer containing triaryl imidazole pendent group, 4-[4-（4,5-diphenyl-1H-imidazol-2-y1）phe- noxy]-1,3-benzenediamine, was synthesized via aromatic substitution reaction of 1-chloro-2,4-dinitrobenzene with 4-（4,5- diphenyl-1H-imidazol-2-y1）pbenol, followed by palladium-catalyzed hydrazine reduction. This new monomer was further confirmed by FT-IR, IH NMR and ^13C NMR. Novel polyamides having pendant triaryl imidazole group were prepared by the phosphorylation polycondensation of four commercially aromatic dicarboxylic acids with the prepared diamine. Inherent viscosities of polyamides were in the range 0.42-0.53 dL/g indicating formation of medium molecular weight polymers. polyamides exhibited glass-transition temperature （Tg） in the range 236-265 ℃. These polymers are essentially amorphous and were soluble in polar aprotic solvents such as DMF, NMP, DMAc. The 10% weight loss temperatures in air atmosphere, measured by TGA were in the range 350-373 ℃ indicating their good thermal stabilities. ？2009 Mousa Ghaemy. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： polyamides Bulky pendent group Thermal properties Imidazole

Synthesis and Characterization of polyamides Based on Dimer Acid

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Journal of Wuhan University of Technology(Materials Science) 2009年第3期24卷 367-370页

作者：王文志章永化 College of Materials Science and Engineering South China University of Technology

A series of dimer acid-based polyamides were synthesized by melt-polycondensation of dimer acid and various aromatic diamines, and were characterized by Fourier transform infrared spectrum （FT-IR） and nuclear magnetic resonance （^1H NMR）. The physical properties of the polyamides, such as glass transition temperature, melting temperature, decomposition temperature and mechanical properties were also investigated. The polyamides＇ intrinsic viscosity ranges from 1.8 dL·g^-1 to 2.2 dL·g^-1, and the melting temperature ranges from 140 ℃ to 181 ℃. The glass transition temperatures, observed from dynamic mechanical analysis, fall in the range of 34.8-48.2 ℃. The physical and mechanical properties of the resultant polyamides are similar to those of the PA1212. The heat resistance and mechanical properties of poly （4, 4′-diphenylsulfone dimeramide）（PSD） and poly（4, 4′-di pb enyl dimeramide）（PPDI） are comparable to those of PA 1212.

关键词： polyamides dimer acid polycondensation aromatic diamines

Simultaneous Thermoluminescence and Thermally Stimulated Current in Polyamide

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Journal of Materials Science & Technology 1998年第4期14卷 357-360页

作者： Fan, Yong Wang, Xuan Zhang, Xiaohong Lin, Jiaqi Lei, Qingquan Harbin Univ Sci & Technol Dept Elect Mat Engn Harbin 150040 Peoples R China

The simultaneous thermoluminescence (TL) and thermally stimulated current (TSC) spectra were obtained in two types of polyamide film, such as nylons 6 and 11 under study of electron detrapping and recombination. There are three main relaxation peaks or regions, designated gamma , beta and alpha in order of increasing temperature in the TSC spectra, in contrast, a high temperature relaxation peak in TL spectra disappears. The centers of peaks of these relaxation regions are located at near 180, 230 and 310 K, respectively, deviating plus or minus 10 K. However, two anomalous phenomena were observed: firstly, a very large, short-circuited, thermally stimulated discharge current (TSDC) is up to 10** minus **8A, but reversible in direction for non-polarized nylons 6 and 11, even after several times repeatedly; secondly, there is no TL signal except for non-polarized nylon 6 film. (Edited author abstract) 11 Refs.

关键词： polyamides

Depolymerization of polyamide 6 in hydrophilic ionic liquids

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Green Energy & Environment 2019年第2期4卷 166-170页

作者： Akio Kamimura Yuto Shiramatsu Takuji Kawamoto Department of Applied Chemistry Yamaguchi University

Polyamide 6 underwent an efficient depolymerization in hydrophilic ionic liquids under microwave irradiation at 300C. The depolymerization completed within 60 min. Caprolactam was readily separated by simple extraction procedure and the ionic liquids were recovered and reused for several times. Addition of catalytic amounts of DMAP(N,N-dimethylaminopyridine) promoted the depolymerization effectively.The present improved procedure provides a method to avoid direct distillation procedure, which consumes energy for the separation of caprolactam from ionic liquids. Although some contamination of ionic liquids was observed, the present procedure provides a new possibility for the use of ionic liquids for plastic chemical recycling from the viewpoint of development of an energy-saving methodology. Use of solubility switchable ionic liquids is also examined to explore a possibility for better separation although depolymerization did not work well.

关键词： Chemical recycling polyamides Chemical conversion Ionic liquids