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1.
Novel thermally stable and organosoluble poly(thiourea-amide-imide)s (PTAIs) were synthesized through the condensation of various diamines with a new kind of aromatic diacid chloride monomer containing pyridine units, 2-(3-(2-(3-(chlorocarbonyl)pyridin-2-yl)-1,3-dioxoisoindoline-5-carbonyl) thioureido) nicotinoyl chloride, CPDITNC. Spectroscopic and elemental analyses were carried out for the structure elucidation of synthesized monomers. Accordingly, the ensuing PTAIs were characterized by FTIR, 1H and 13C NMR techniques along with crystallinity, organosolubility, inherent viscosity and GPC measurements. Consequently, polymers bearing phenyl thiourea and pyridine moieties in the backbone exhibited good organosolubility in a variety of highly polar solvents such as DMAc, DMF, DMSO and NMP. PTAIs encompassed ηinh of 1.24-1.46 dL/g and two of the polymers showed crystalline behavior. Moreover, GPC measurements of polymers revealed Mw around 33,000-50,000. Thermal stability of these polymers was ascertained via 10% weight loss temperatures in the range of 548-562 °C (inert atmosphere). Ultimately, these polymers own high glass-transition temperatures about 264-270 °C. 相似文献
2.
A novel series of N′‐(substituted benzylidene)‐2‐(5,6‐dichloro‐2‐methyl‐1H‐benzimidazol‐1‐yl)acetohydrazides and N′‐(1‐(substituted phenyl)ethylidene)‐2‐(5,6‐dichloro‐2‐methyl‐1H‐benzimidazol‐1‐yl)acetohydrazides were synthesized and then studied for their urease inhibitory activities using thiourea as a standard drug. All newly synthesized compounds were found to exhibit potent inhibitory properties against urease enzyme in the range of IC50 = 0.0155 ± 0.0039–0.0602 ± 0.0071 μM, when compared with the thiourea as standard (IC50 = 0.5115 ± 0.0233 μM). All target molecules were characterized by 1H‐NMR, 13C‐NMR, IR, and electrospray ionization mass spectrometry. 相似文献
3.
Vernica Caldern Flix C. García Jos L. De La Pea Eva M. Maya Jos M. García 《Journal of polymer science. Part A, Polymer chemistry》2006,44(7):2270-2281
Two novel isophthalic diacid‐based monomers have been synthesized by inclusion in ring position 5 of a functionalized benzoylamine moiety. The functionalization includes a 12‐crown‐4 ether group fused with the benzene subunit and a dipodand substructure, formally a disubstitution of the benzene ring, with two sequences of ethyl‐terminated ethylene oxide units, which represent the open‐chain counterpart of the alicylic crown moiety. The polycondensation of the two diacids with five aromatic diamines yielded 10 new polyamides with crown or podand pendant substructures. The polyamides had previously been chemically characterized by NMR, IR, and elemental analysis. The polymers showed high glass transition temperatures of up to 349 °C, good thermal stability (Tdonset, N2 ≈ 400 °C), and improved solubility in organic solvents. The presence of acyclic or alicyclic oxyethylene sequences as crown ether or podand substructures and an additional amide side group per repeat unit made the polymers essentially amorphous and improved their water absorption ability in comparison with nonsubstituted polyamides. Water uptake values as high as 12% were observed at 65% relative humidity. All the polyamides showed a good film‐forming ability, and the mechanical properties of these films are considered to be satisfactory for experimental aromatic polyamides. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2270–2281, 2006 相似文献
4.
Habibe Tezcan Hülya ?en?z Nesrin Tokay 《Monatshefte für Chemie / Chemical Monthly》2012,287(11):579-588
Abstract
1-[(NO2, COOH)-substituted phenyl]-3,5-diphenylformazans were synthesized. The compounds were characterized by infrared (IR), ultraviolet–visible (UV–vis), 1H nuclear magnetic resonance (NMR), 13C NMR spectra, elemental analysis, and cyclic voltammetry. From the UV–vis spectra of substituted formazans it was seen that λ max values were shorter than the λ max value of unsubstituted formazan. It was observed that the shift values were dependent on the type and position of the substituents. A correlation between Hammett substituent coefficients and λ max values was obtained. The oxidation peak potentials of substituted formazans were found more anodic than that of unsubstituted formazan. The oxidation mechanism was a single step for the NO2-substituted formazans, and two steps for COOH-substituted formazans. 相似文献5.
Balgar Singh Simpy Mahajan Haq N. Sheikh Mohita Sharma Bansi L. Kalsotra 《Monatshefte für Chemie / Chemical Monthly》2012,51(5):91-99
Abstract
Uranium(VI) peroxo complexes of composition [UO(O2)L–L(NO3)2], where L–L are the Mannich base ligands morpholinobenzyl urea, piperidinobenzyl urea, morpholinobenzyl thiourea, piperidinobenzyl thiourea, morpholinomethyl thiourea, piperidinomethyl thiourea, or morpholinomethyl urea, are reported. The synthesized complexes were characterized by use of a variety of physicochemical techniques, viz. elemental analysis, molar conductivity, magnetic susceptibility measurements, IR, electronic, mass, 1H NMR, and 13C NMR spectroscopy, and TGA/DTA studies. These studies revealed that the complexes are both non-electrolytic and diamagnetic in nature. The ligands are bound to the metal in a bidentate mode through carbonyl oxygen or thiocarbonyl sulfur and the ring nitrogen. Mass spectra confirm the molecular mass of the complexes. The antifungal activity of the complexes is greater than that of the corresponding free ligands. 相似文献6.
Several optically active aromatic polyamides have been synthesized via direct polycondensation of chiral diacid monomer 1 containing l-methionine moiety with diverse aromatic diamines 2a–2h in a green medium, namely 1,3-dipropylimidazolium bromide as a room temperature ionic liquid. In order to evaluate the advantages
of microwave promotion of these polymerization reactions, we compared microwave irradiation (method I) with conventional oil
bath heating (method II) by means of reaction rates, conversions, and inherent viscosities. The inherent viscosities of resulting
polymers were ranging between 0.47–0.65 and 0.35–0.57 dL/g in methods I and II, respectively. These polymers were characterized by means of 1H-NMR, FT-IR, elemental, organosolubility, differential scanning calorimetry, and thermal gravimetric analysis techniques.
The obtained polymers show thermal stability up to 273 °C under nitrogen atmosphere and good solubility in polar organic solvents.
Polymerization reactions proceeded in higher yields and moderate inherent viscosities under microwave irradiation conditions
besides the dramatically shorter reaction times and achieving the more pure products. 相似文献
7.
E-(4-β-D-Allopyranosyloxyphenyl)-1-(4-substituted phenyl)propenone derivatives (1a–g) have been synthesized by the Claisen-Schmidt condensation of helicid with 4-substituted acetophenone using 10% NaOH aqueous
solution as a catalyst. 6H-2-Amino-4-aryl-6-(4-β-D-allopyranosyloxyphenyl)-1,3-thiazine (2a–g) were synthesized by the 1,4-Michael reaction of 1a–g with thiourea. The structures of all the new products were established by 1H NMR, IR, and MS spectroscopy. Compound 2b (200 mg·kg–1) showed better sedative-hypnotic activity, so further modification of helicid should be worthwhile. 相似文献
8.
Aslam B. Tamboli Rajesh G. Bhorkade Basavraj S. Kalshetti Shivaji D. Ghodake 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):983-993
AbstractA new series of soluble aromatic polyamides was synthesized by low temperature solution polycondensation of novel aromatic diamine namely 3,5-bis-(4′-amino phenyl)-4-(4″-methoxy-2″-pentadecyl phenyl) 1,2,4-triazole (VII) with aromatic diacid chlorides, viz. isophthaloyl chloride (IPC) and terephthaloyl chloride (TPC). The aromaticdiamine (VII) was characterized by elemental analysis, FT-IR, NMR (1H, 13C), and mass spectrometry. Copolyamides were also synthesized by employing various mole proportions of IPC and TPC with diamine (VII). Inherent viscosities of these polyamides were in the range of 0.50–0.65 dL/g in DMAc, indicating formation of moderate to high molecular weight of polyamides. These polyamides showed good solubility in polar aprotic solvents such as N,N-Dimethyl acetamide (DMAc), N-Methyl 2-pyrrolidone (NMP), N, N, Dimethyl formamide (DMF), and Dimethyl sulphoxide (DMSO), which may be due to incorporation of pendant methoxyphenyl moiety with pentadecyl units. The amorphous morphology of polyamides as evidenced by XRD. These polyamides had lower glass transition temperatures; as determined by DSC, compared to the Tg of conventional aromatic polyamides due to internal plasticization effect of long alkyl pentadecyl group. Polymers showed good thermal stability, with initial decomposition temperature above 300?°C. 相似文献
9.
Vinyltri(phenylethynyl)silane ((ph–C≡C)3–Si–C=CH2; VTPES) and phenyltri(phenylethynyl)silane ((ph–C≡C)3–Si–ph; PTPES) were synthesized by Grignard reaction. Their molecular structures were characterized by means of 1H NMR, 13C NMR, 29Si NMR, and FT-IR spectroscopy. Their nonisothermal thermal curing processes were characterized by DSC, and the corresponding
kinetic data, for example activation energy (E), pre-exponential factor (A), and the order of the reaction (n), were obtained by the Kissinger method. The results showed that the melting points of VTPES and PTPES were 84 and 116 °C,
respectively. Their curing reaction rates were consistent with first-order kinetic equations. VTPES monomer had a lower activation
energy and curing temperature as a result of coordination between reactive groups. 相似文献
10.
A novel polymer-forming diimide–diacid, 5,5′-bis[4-(4-trimellitimido phenoxy)phenyl]-hexahydro-4,7-methanoindan (II), was prepared by the condensation reaction of 5,5′-bis[4-(4-aminophenoxy)phenyl]-hexahydro-4,7-methanoindan with trimellitic
anhydride. A series of novel aromatic poly(amide–imide)s (PAIs) containing polycyclic cardo groups was prepared by the direct
polycondensation of II with various aromatic diamines using phosphorylation techniques. The polymers had inherent viscosities between 0.71 and 0.96 dl/g.
The polymers were soluble in polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide (DMAc) and N,N-dimethylformamide, and could be cast from their DMAc solutions into transparent, flexible, and tough films, except for III
a
. These films had yield strengths of 85–114 MPa, tensile strengths of 77–102 MPa, an elongation at break of 8–17%, and initial
moduli of 2.0–2.7 GPa. Wide-angle X-ray diffraction revealed that the polymers are amorphous. The glass-transition temperatures
of the polymers were in the range 242–312 °C. All the PAIs exhibited no appreciable decomposition below 430 °C, and their
10%-weight-loss temperatures were in the range 484–507 °C in nitrogen and 494–515 °C in air.
Received: 26 January 1999 Accepted in revised form: 11 May 1999 相似文献
11.
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(Tg) in the range of 138-210℃. Their initial decomposition temperature(Ti) varied from 265℃to 310℃under N2.The dilute solution(0.2 g/dL) of polyamides in DMF exhibited fluorescence emission withλmax in the range of 470-550 nm. 相似文献
12.
Aromatic polyamides were synthesized from 4,5-bis(4-aminophenyl)-2-phenyloxazole (APO) or 4,5-bis[4(4-aminophenoxy)phenyl]-2-phenyloxazole (APPO) containing 2-phenyl-4,5-oxazolediyl units with several aromatic carboxylic dichlorides by a low-temperature solution polycondensation method. The polyamides were obtained quantitatively, and their inherent viscosities ranged from 0.48 to 1.25 dL g?1. The glass transition temperatures (T gs) were displayed between 234 to 311°C, and the residual weight at 600°C (Res.wt600) exceeded 52% in nitrogen atmosphere. The polyamides showed good solubility in several aprotic polar solvents, such as N,N-dimethylacetoamide (DMAc), N-methyl-2-pyrrolidone (NMP), and dimethyl sulfoxide (DMSO). Aromatic polyimides were derived from APO or APPO with aromatic carboxylic dianhydrides through polyamic acids. The inherent viscosities of the polyamic acids, which were 0.53 to 1.02 dL g?1, T gs of the polyimides were observed between 259 to 361°C and their Res.wts600 were above 70%. The polyamides and polyimides were amorphous and afforded thin, flexible and tough films. We also prepared a nanocomposite of the polyamide derived from APPO with organophilic montmorillonite clay. 相似文献
13.
Shafqat Nadeem Muhammad Khawar Rauf Saeed Ahmad Masahiro Ebihara Syed Ahmed Tirmizi Sarfaraz Ahmed Bashir Amin Badshah 《Transition Metal Chemistry》2009,34(2):197-202
Palladium(II) complexes of thiones having the general formula [Pd(L)4]Cl2, where L = thiourea (Tu), methylthiourea (Metu), N,N′-dimethylthiourea (Dmtu), and tetramethylthiourea (Tmtu) were prepared by reacting K2[PdCl4] with the corresponding thiones. The complexes have been characterized by elemental analysis, IR and NMR spectroscopy, and
two of these, [Pd(Dmtu)4]Cl2 · 2H2O (1) and [Pd(Tmtu)4]Cl2 (2), by X-ray crystallography. An upfield shift in the >C=S resonance of thiones in 13C NMR and downfield shift in N–H resonance in 1H NMR are consistent in showing sulfur coordination with palladium(II). The crystal structures of the complexes show a square-planar
coordination environment around the Pd(II) ions with the average cis and trans S–Pd–S bond angles of 89.64° and 173.48°, respectively.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
14.
Ravindra R. Pal Manikrao M. Salunkhe Noormahmad N. Maldar 《European Polymer Journal》2009,45(3):953-1289
Four new aromatic polyamides containing pendant groups were synthesized by low temperature interfacial polycondensation of two asymmetrically substituted diamine monomers, namely, 4-[4-(1-methyl-1-phenylethyl) phenoxy]-1,3-diamino benzene and 4-{4-[(4-methylphenyl) sulphonyl]phenoxy}-1,3-diamino benzene with two aromatic diacid chlorides, namely isophthaloyl chloride and terephthaloyl chloride. Inherent viscosities of polyamides were in the range 0.64-0.72 dL/g indicating formation of medium molecular weight polymers. The weight average molecular weights and number average molecular weights, determined by gel permeation chromatography (polystyrene standard), were in the range 54,500-65,000 and 19,750-27,000, respectively. The constitutional isomerism of synthesized polyamides was investigated by 1H and 13C NMR spectroscopy, where as the constitutional order was calculated from 1H NMR spectroscopy and was found to be in the range 0.35-0.37. Polyamides containing pendant groups were essentially amorphous and were soluble in polar aprotic solvents such as N, N-dimethyl acetamide, N-methyl-2-pyrrolidone, N, N-dimethyl formamide and dimethyl sulfoxide. Polyamides exhibited glass-transition temperature in the range 237-254 °C. The initial decomposition temperature, determined by TGA in nitrogen atmosphere, of polyamides was in the range 371-410 °C indicating their good thermal stability. 相似文献
15.
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 H2SO4 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℃. 相似文献
16.
New monomers, bis(3-ethynyl)dianilides, were synthesized from 3-ethynylaniline and different diacid dichlorides and were polymerized by oxidative polycoupling to give soluble high molecular weight film forming diacetylene-containing polyamides. UV-induced and thermal cross-linking of the polymer were studied. A correlation was found between the chain flexibility and the absoprtion peaks of visible spectra of cross-linked polymer films. Third order nonlinear optical susceptibility (χ(3)) of the polymer films was in the range of 10−10-10−9 esu. 相似文献
17.
Mikio Kajiyama Jun Kudo Hiroshi Mizumachi 《Journal of polymer science. Part A, Polymer chemistry》1999,37(8):1135-1141
A series of polyisophthalamides and polyisophthalates having perfluorinated side chains were prepared from 5‐perfluoroalkylisophthaloyl dichlorides. The aromatic polyamides and polyarylates synthesized by conventional low temperature solution polycondensation and interfacial polycondensation, respectively, had inherent viscosities of 0.19 to 1.28 dL g−1 in yields of 65 to 100%. Solubilies of the resulting polymers were improved by incorporating nonafluorobutyl groups but not improved by incorporating heptadecafluorooctyl groups. Although the effect on the glass transition temperature (Tg) of incorporating perfluoroalkyl groups into the aromatic polyamides or polyarylate backbone is great, the incorporation maintained the thermal stability of the polymers. In spite of the rigid nature of perfluoroalkyl groups, Tgs were decreased by incorporating perfluoroalkyl groups. The value of the contact angle of water on the aromatic polyamides films gradually increased with incorporation of the perfluoroalkyl groups. On the other hand, the value of the contact angle remarkably increased when perfluoroalkyl groups were incorporated into polyarylates. The Owens γs were also calculated for some aromatic polyamides by measuring contact angles of diiodomethane on the polymer films. The γs were estimated at 23‐37 mN m−1 and about 10% of them were contributed by hydrogen bonding. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1135–1141, 1999 相似文献
18.
Polyurethane cationomers were synthesised in the reaction of 4,4′-methylenebis(phenyl isocyanate) with polyoxypropylene glycol
(M = 450) and N-methyl diethanolamine. Amine segments were built-in to the urethane–isocyanate prepolymer in the reaction with 1-bromoalkanes
(C2–C10), and then they were converted to alkyl-ammonium cations. The obtained isocyanate prepolymers were then extended in the aqueous
medium. That yielded stable aqueous dispersions which were applied on the surfaces of test poly(tetrafluoroethylene) plates.
After evaporation of water, the dispersions formed thin polymer coatings. 1H and 13C NMR spectral methods were employed to confirm chemical structures of synthesised cationomers. Based on 1H NMR and IR spectra, the factors κ and α1 or α1 were calculated, which represented the polarity level of the obtained cationomers. The differential scanning calorimetry
method revealed decline of T
g for the hard urethane and urea segments from 60 °C to 46 °C when the number of carbon atoms increased in the alkyl radical
attached to the ammonium cation. Changes were discussed in the surface free energy (SFE) and its components, as calculated
independently according to the methods suggested by van Oss-Good and by Owens–Wendt, in relation to chemical structures of
cationomers. The growing length (from C2 to C10) of the alkyl radical attached to the N atom in the cationomer chain was found to reduce the value of SFE of the polymer coating from 46 to 28 mJ/m2. That is caused by gradual weakening of long-range interactions, within which the highest share is taken by dispersion interactions. 相似文献
19.
Yaw-Terng Chern Hann-Chyan Shiue Shen C. Kao 《Journal of polymer science. Part A, Polymer chemistry》1998,36(5):785-792
This work synthesized a series of new polyamides by direct polycondensation of 1,3-bis[4-(4-carboxyphenoxy)phenyl]adamantane ( I ) with various diamines. The diacid I was synthesized from 1,3-bis(4-hydroxyphenyl)adamantane in two steps. Polyamides III were soluble in N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc), and pyridine. The polyamides had medium inherent viscosities of 0.30–0.55 dL/g and number-average molecular weights (Mn) of 22,000–36,000. The polyamides III a and III b had tensile strengths of 59.8 and 77.5 MPa, elongation to breakage values of 5.8 and 7.6%, and initial moduli of 1.9 and 1.8 GPa, respectively. Their glass transition temperatures were found to be 219–295°C by means of differential scanning calorimetry (DSC). Dynamic mechanical analysis (DMA) reveals that the incorporation of rigid and bulky diamantane into polyamides III a and III b leads to high glass transition temperatures (Tgs), at 299 and 286°C, respectively. The decomposition temperatures of polyamides III at a 5% weight loss ranged from 388 to 416°C in air and from 408 to 435°C in N2 atmosphere. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 785–792, 1998 相似文献
20.
Yagoub Mansoori Behzad Koohi-Zargar Hemayat Shekaari Mohammad Reza Zamanloo Gholam Hassan Imanzadeh 《高分子科学》2012,(1):112-121
A novel aromatic diamine,2-(5-(3,5-diaminophenyl)-l,3,4-oxadiazole-2-yl)pyridine(POBD),containing a pyridine ring and a 1,3,4-oxadiazole moiety,was synthesized.It was used in a polycondensation with various aromatic and aliphatic diacid chlorides to generate a series of new aromatic polyamides with pendant 1,3,4-oxadiazole groups.The prepared polyamides were characterized by IR,elemental analysis and through the synthesis of model compounds.Thermophysical properties of the synthesized polyamides have been studied by DSC,TGA and inherent viscosity measurements. Relatively high inherent viscosity values(0.76-1.62 dL/g,in 0.125%H2SO4 at 25℃) were observed for these compounds. Number average molecular weight(Mn) of the polymers was measured by vapor phase osmometry(VPO).The introduction of bulky side chains in the structure of aromatic polyamides led to increased solubility of these polymers in common polar and aprotic solvents,such as DMF,DMSO,NMP and DMAc,which allowed thin films to be cast from polymer solutions. The highest molecular weight(Mn = 51190) was observed for polymer(DC),which was prepared from pyridine-2,6-dichlorocarbonyl. 相似文献