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1.
<正>Six new optically active and flame-retardant poly(amide-imide)s PAIs 5a-5f containing phosphine oxide moiety as a flame-retardant unit in the main chain were synthesized from direct polycondensation reaction of six chiral N,N′-(pyromellitoyl)-bis-L-amino acid 3a-3f with bis(3-aminophenyl)phenyl phosphine oxide 4 in a medium consisting of N-methyl-2-pyrrolidone(NMP),triphenyl phosphite(TPP),calcium chloride(CaCl_2) and pyridine.The polymerization reactions produced a series of optically active poly(amide-imide)s with good yield and good inherent viscosity of 0.34-0.70 dLg~(-1).The resulted polymers were fully characterized by means of FTIR and ~1H-NMR spectroscopy,gel permeation chromatography(GPC),elemental analyses,inherent viscosity and solubility tests.Thermal properties and flame-retardant behavior of the PAIs 5a-5f were investigated using thermal gravimetric analysis(TGA and DTG) and limiting oxygen index(LOI).Data obtained by thermal analysis(TGA and DTG) revealed that these polymers showed good thermal stability.Furthermore,high char yield in TGA and good LOI values indicated that the resulting polymers were capable of exhibiting good flame retardant properties.N,N′-(pyromellitoyl)-bis-L-amino acids 3a-3f were prepared in quantitative yields by the condensation reaction of pyromellitic dianhydride(1,2,4,5-benzenetetracarboxylicacid-1,2,4,5-dianhydride) 1 with L-alanine 2a,L-valine 2b,L-leucine 2c,L-isoleucine 2d,L-phenyl alanine 2e and L-2-aminobutyric acid 2f in acetic acid solution.  相似文献   

2.
Six new optically active poly(amide-imide)s(5a-f) were synthesized through the direct polycondensation reaction of N,N'-(4,4'- diphthaloyl)-bis-L-leucine(3) with six hydantoin derivatives(4a-f).Triphenyl phosphite(TPP)/pyridine in the presence of calcium chloride(CaCl_2) and N-methyl-2-pyrrolidone(NMP) were successfully applied for direct polycondensation.The polycondensation reactions produce a series of new poly(amide-imide)s(5a-f) in high yields,and inherent viscosity between 0.42 and 0.55 dL/g.The re...  相似文献   

3.
Eight novel poly(amide-imide)s were synthesized under microwave irradiation by using a domestic microwaveoven from the polycondensation reactions of N,N′-(pyromellitoyl)-bis-L-alanine diacid chloride (1) with eight different derivatives of hydantoin compounds (2a-h) in the presence of a small amount of a polar organic medium such as o-cresol. The polycondensation proceeded rapidly, compared with the conventional solution polycondensation and was completed within 8-10min, producing a series of new poly(amide-imide)s (3a-h) with inherent viscosities about 0.35-0.68dL/g in high yields. The obtained PAIs (3a-h) were fully characterized by means of FT-IR spectroscopy, elemental analyses, inherent viscosity (ηinh), solubility and specific rotation measurements. All of the resulting polymers show optical rotation and are optically active. Thermal properties of the poly(amide-imide)s were investigated by using thermal gravimetric analysis(TGA).  相似文献   

4.
<正>New organo-soluble poly(amide-imide)s(PAIs) 8a-8f were prepared from newly synthesized 1,2-bis[4,4'-(trimellitimido) phenoxy]ethane 6 via direct polycondensation with various aromatic diamines.The diacid 6 was synthesized by the condensation reaction of 12-bis[4-atninophenoxy]ethane 4 with trimellitic anhydride 5 in acetic acid.All polymers were obtained in quantitative high yields with inherent viscosities of 0.48-0.61 dL/g.All of these polymers were highly soluble in organic solvents such as,N-methyl-2-pyrrolidone(NMP),dimethylformamide(DMF),N,N'-dimethylacetamide (DMAc) and dimethylsulfoxide(DMSO) at room temperature and were fully characterized by means of NMR spectroscopy, FTIR spectroscopy,elemental analyses,inherent viscosity,solubility test,specific rotation,differential scanning calorimetry (DSC) and thermogravimetric analysis(TGA).  相似文献   

5.
Facile and rapid polycondensation reactions of N,N′-(pyromellitoyl)-bis-L-leucine diacid chloride 1 with eight different derivatives of hydantoin compounds 2a-h were developed by using a domestic microwave oven in the presence of a small amount of polar organic medium such as o-cresol. The polycondensation reactions proceeded rapidly, compared with the conventional solution polycondensation, and was completed within 7-10 min, producing a series of novel optically active poly(amide-imide)s 3a-h with high yield and inherent viscosity of 0.35-0.65 dL/g. All of the above polymers were fully characterized by FT-IR, elemental analyses, inherent viscosity (ηinh), solubility test and specific rotation. Some structural characterization and physical properties of these optically active poly(amide-imide)s are reported.  相似文献   

6.
<正>A novel calix[4]arene derivative 2 with amino functional groups at the lower rim was first prepared via introduction of nitro functional groups and amination of the dinitro derivative of calix[4]arene.The optically active monomers were synthesized by dehydration of L-leucine(and L-isoleucine) and 3,3',4,4'-benzophenonetetracarboxylic- 3,3',4,4'-dianhydride(3) followed by reaction with thionyl chloride to form 5a and 5b.Two methods,polymerization under microwave irradiation and solution polymerization in CH_2Cl_2/TEA,were then employed to carry out the condensation polymerization of 2 with the optically active monomers 5a and 5b,respectively.The polymerization conditions affected the kind of resulting polymers,poly(amide-imide)s(PAIs) 6a and 6b and poly(ester-imide)s(PEIs) 6a' and 6b' were obtained selectively in good yields and moderate inherent viscosities.Sorption-extraction experiments were carried out using cram picrate extraction method and verified good binding ability of the resulting calixarene-based polymers towards silver,alkali metal and toxic heavy metal cations.Also thermogravimetric analysis indicated that the resulting PAIs and PEIs were thermally stable.  相似文献   

7.
A series organosoluble and heterocyclic poly(ether-amide)s (PEA)s were synthesized from a new diamine containing pyridine moiety and four aliphatic-aromatic dicarboxylic acids by direct polycondensation reactions. Dicarboxilic acids 4a-4d containing ether groups were synthesized in two step reactions. At first, dialdehydes 3a-3d were synthesized from four dibromo alkanes la-ld and 4-hydroxybenzaldehyde 2, then dicarboxilic acids 4a-4d were synthesized from dialdehydes 3a-3d and malonic acid in a solvent free reaction. On the other hand, the new diamine 8 containing pyridine ring was synthesized in two step reactions. The structures of synthesized monomers and polymers were proven by FTIR, NMR spectroscopy and elemental analysis. Also all of the above polymers were fully characterized by inherent viscosity, solubility tests, gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The resulted PEAs have shown good inherent viscosities, solubility and thermal properties.  相似文献   

8.
<正>Five new optically active polyamides(PAs) 6a-6e were prepared by direct polycondensation reaction of 2-(1,3- isoindolinedione-2-yl)-glutaric acid 4 as a new chiral diacid with various aromatic diamines 5a-5e in a medium consisting of triphenyl phosphite(TPP),calcium chloride,pyridine(Py) and N-methyl-2-pyrrolidone(NMP).The polycondensation reaction produced a series of polyamids 6a-6e in quantitative yields with inherent viscosities of 0.26-0.39 dL/g.The resulting polymers were fully characterized by means of ~1H-NMR,FT-IR spectroscopy,elemental analysis,inherent viscosity and specific rotation.Thermal properties of these polymers were investigated using thermal gravimetric analysis (TGA) and differential thermal gravimetry(DTG).Phthalimide rings as a bulky pendent group in the polymer chains disturb the interchain and intrachain interactions and make these PAs readily soluble in polar,aprotic solvents such as N,N-dimethyl acetamide(DMAc),N,N-dimethyl formamide(DMF),dimethyl sulfoxide(DMSO),N-methyl-2-pyrrolidone(NMP) and sulfuric acid.  相似文献   

9.
Eight novel poly(amide-imide)s were synthesized under microwave irradiation by using a domestic microwaveoven from the polycondensation reactions of N.N'-(pyromellitoyl)-bis-L-alanine diacid chloride(1)with eight differentderivatives of hydantoin compounds(2a-h)in the presence of a small amount of a polar organic medium such as o-cresol.The polycondensation proceeded rapidly,compared with the conventional solution polycondensation and was completedwithin 8-10 min,producing a series of new poly(amide-imide)s(3a-h)with inherent viscosities about 0.35-0.68 dL/g inhigh yields.The obtained PAIs(3a-h)were fully characterized by means of FT-IR spectroscopy,elemental analyses,inherentviscosity(ηinh),solubility and specific rotation measurements.All of the resulting polymers show optical rotation and areoptically active.Thermal properties of the poly(amide-imide)s were investigated by using thermal gravimetric analysis(TGA).  相似文献   

10.
In order to synthesize new polyamide(PA) 5 and copolyamides(Co PA) 7a-7d, a new-type of dicarboxylic acid containing triazine ring was successfully synthesized from 2,4-dichloro-6-methoxy-s-triazine 1 and 4-aminobenzoic acid. New polyamide 5 containing triazine moiety was prepared from 4,4'-(6-methoxy-1,3,5-triazine-2,4-diyl)bis(azanediyl)dibenzoic acid 3 and 4,4′-diaminodiphenylether by direct polycondensation reaction. Then new series thermally stable copolyamides 7a-7d with high solubility in common organic solvents were synthesized from the direct polycondensation reaction of diacid 3 as a first monomer, aliphatic-aromatic diacids 6a-6d as second diacids and 4,4′-diaminodiphenylether. All of the above polymers were fully characterized by 1H-NMR and FTIR spectroscopy, elemental analysis(CHN), inherent viscosity, solubility tests, gel permeation chromatography(GPC), differential scanning calorimetry(DSC) and thermogravimetric analysis(TGA). The resulted Co PAs 7a-7d have shown good inherent viscosities, solubility and thermal properties.  相似文献   

11.
<正>Six new polyesters 7a-f were synthesized through the solution polycondensation reaction of diacid chloride 5 with six aromatic diols 6a-f in N,N-dimethyl acetamide(DMAc) as solvent in the presence of pyridine as base.The polycondensation reaction produced a series of novel polyester containing pyridyl moiety in the main chain in high yields with inherent viscosities between 0.35 and 0.54 dL/g.The resulted polymers were fully characterized by means of FT-IR spectroscopy,elemental analyses,inherent viscosity and solubility tests.Thermal properties of these polymers were investigated by using thermal gravimetric analysis(TGA) and differentional thermal gravimetric(DTG).The glass-transition temperatures of these polyesters were recorded between 130 and 170℃by differential scanning calorimetry(DSC) and the 10%weight loss temperatures were ranging from 390 to 450℃under nitrogen.  相似文献   

12.
<正>Based on several unsymmetrical,twist,noncoplanar phthalazinone-containing monomers 2a-2e and an active bis(4-fluorophenyl)phenyl phosphine oxide(BFPPO) monomer,a series of novel poly(phthalazinone ether phosphine oxide)s (PPEPO) was synthesized by anhydrous K_2CO_3 mediated N—C coupling reaction in DMAc.The polymers exhibited good thermal properties with T_gs ranging from 267℃to 306℃and 5%weight loss temperatures in nitrogen higher than 430℃, together with high char yield upon prolonged heating at 800℃(35%—56%).Moreover,the polymers were readily soluble in common organic solvents,such as N-methyl-2-pyrrolidone,chloroform and m-cresol.These polymers had inherent viscosities in the range of 0.45-0.72 dL/g and could be cast into flexible and colorless films by spin coating or casting approach.  相似文献   

13.
<正>A series of new optically active poly(amide-imide)s were synthesized by direct polycondensation reaction of 4,4'-diaminochalcone with several N-trimellitylimido-L-amino acids using a tosyl chloride(TsCl),pyridine(Py) and dimethylformamide(DMF) system as condensing agent.The resulting thermally stable poly(amide-imide)s were obtained in good to high yields and inherent viscosities ranging between 0.35 dL/g and 0.58 dL/g and were characterized with FTIR, ~1H-NMR,CHN,Ultraviolet,TGA and DTG techniques.  相似文献   

14.
Poly(arylene ether diketone)s were prepared by the aromatic nucleophilicdisplacement reaction of 4,4'-difluorobenzil with different bisphenols in the presence of an-hydrous potassium carbonate in diphenylsulfone at elevated temperature. The polymersobtained had inherent viscosity of 0.51 ~ 0.63 dL/g, and exhibited glass transition temper-ature ranging from 136 ~217℃ mainly depending on the bisphenols used in the polymersynthesis. Thermogravimetry of these polymers showed excellent thermal stability, indi-cating that 10% weight losses of the polymers were observed in the range above 428℃ and438℃ in air and nitrogen, respectively. The mechanical properties of these polymers werealso described and the permeability of five polymers for H_2, O_2 and N_2 was determined at30℃.  相似文献   

15.
<正>In this article,six new optically active copoly(amide-imide)s(10a-f) were synthesized through the direct polycondensation reaction of N-phthalimido-L-aspartic acid(4) with 1,5-diamino naphthalene(8),3,4-diamino benzophenone(9) in the presence of therphthahc acid(7),fumaric acid(6) and adipic acid(5) as a second diacid in a medium consisting of N-methyl-2-pyrrolidone,triphenyl phosphite, calcium chloride and pyridine.The resulting copolymers were fully characterized by means of FT-IR spectroscopy,elemental analyses, inherent viscosity,solubility tests and UV-vis spectroscopy.Thermal properties of resulting copolymers(10a-c) containing three different second diacid in the main chain were compared by using TGA and DTG thermograms.  相似文献   

16.
程琳  应磊  杨小玲  蹇锡高 《中国化学》2005,23(2):200-203
A new monomer diacid, 1,2-dihydro-2-(4-carboxylphenyl)-4-[4-(4-carboxylphenoxy)-3-methylphenyl]phtha-lazin-1-one (3), was synthesized through the aromatic nucleophilic substitution reaction of a readily available unsymmetrical phthalazinone 1 bisphenol-like with p-chlorobenzonitrile in the presence of potassium carbonate in N,N-dimethylacetamide and alkaline hydrolysis. The diacid could be directly polymerized with various aromatic diamines 4a-4e using triphenyl phosphite and pyridine as condensing agents to give five new aromatic poly(ether amide)s 5a-5e containing the kink non-coplanar heterocyclic units with inherent viscosities of 1.30-1.54 dL/g.The polymers were readily soluble in a variety of solvents such as N,N-dimethylformamide (DMF), N,N-dimethyl-acetamide (DMA), dimethylsulfoxide (DMSO), N-methyl-2-pyrrolidinone (NMP), and even in m-cresol and pyridine (Py). The transparent, flexible and tough films could be formed by solution casting. The glass transition tem-peratures Tg were in the range of 286-317℃.  相似文献   

17.
Six new thermally stable polyesters(4a-f) were synthesized through the solution polycondensation reaction of 2,5-pyridine dicarbonyldichloride(2) with six aromatic diols in N,N'-dimethyl acetamide(DMAc) solution and in the presence of pyridine as a base.The polycondensation reactions produce a series of new polyesters(4a-f) in high yields,and inherent viscosity between 0.30 and 0.55 dL/g.The resulting polyesters were characterized by elemental analysis,viscosity measurements,thermal gravimetric analysis(...  相似文献   

18.
Novel aromatic-aliphatic poly(amide-imide)s containing chiral units in the main chain and hydroxyl benzamide units in the side chain have been obtained from the step-growth polymerization of 3,5-diamino-N-(4-hydroxyphenyl) benzamide(2) with different chiral diacid chlorides(1a-1e).Theoretical calculations were done by means of computational chemistry methods to narrate the stable conformation and orientation of each diacid chloride monomers under reaction conditions.These polymers were characterized by conventional techniques.The resulting polymers show good thermal stability.Other physical properties of polymers including crystallinity,inherent viscosity and morphological characteristics were also studied.  相似文献   

19.
<正>An optically active bulky aromatic diacid chiral monomer,(2S)-4-[(4-methyl-2-phthalimidylpentanoyl-amino) benzoylamino]isophthalic acid(1),containing a rigid phthalimide and flexible L-leucine pendent group was synthesized in five steps.A fast and clean method for direct polyamidation reaction of monomer 1 with various aromatic diamines under microwave irradiation and conventional heating was performed.The polymerization reactions provided optically active polyamides with high yields and inherent viscosities in the range of 0.36-0.74 dL/g.Their thermal properties were evaluated by thermogravimetric analysis(TGA) and differential scanning calorimetry.TGA thermograms show that the polymers are thermally stable,10%weight loss temperatures are in excess of 385℃,and char yields at 800℃are higher than 56%.The data obtained from TGA were used to study the kinetics of thermal decomposition of the resulting polymers. The interpretation of kinetic parameters(E,ΔH,ΔS andΔG) of thermal decomposition stages was evaluated using Coats and Redfern equation.  相似文献   

20.
<正>The cationic ring-opening polymerization of 1-azabicyclo[4.2.0]octane,commonly called conidine(1) was studied with some chiral tricyclic amino acid esters(6a-6f) as acylation agents to obtain optically active biopolymers(8a-8f) of the different masses.The structures of the new compounds were confirmed by FT-IR,UV and NMR,and the distribution index of the molecular weights of the polymers was determined from SEC measurements.  相似文献   

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