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1.
The synthesis of 5,11,17,23‐amino‐25,26,27,28‐propoxycalix[4]arene (calix[4]amine, 4 ) starting from 5,11,17,23‐nitro‐25,26,27,28‐propoxy‐calix[4]arene ( 3 ) via microwave‐assisted transfer hydrogenation is reported. Furthermore, the calix[4]amine ( 4 ) is functionalized with an acrylamide moiety. The swelling behavior in water, the influence on the glass transition temperature, and the shear modulus of a crosslinked N,N‐dimethylacrylamide (NDA) polymer with 5,11,17,23‐acrylamido‐25,26,27,28‐propoxycalix[4]arene ( 5 ) and EGDMA, respectively, are investigated.

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2.
A mono methylether Salen-type ligand, SalenMe-H (1) is prepared in a one flask reaction by condensation of trans-1,2-diaminocyclohexane with 2-methoxybenzenaldehyde and followed by the addition of 2,4-di-tert-butylsalicylaldehyde. Further reaction of 1 with Mg(OBn)2 in THF produces a magnesium alkoxide, [(SalenMe)Mg(OBn)]2 (2). Compound 1 reacts with ZnEt2 yields monomeric complex (SalenMe)ZnEt (3), which further reacts with 1 molar equiv of benzyl alcohol giving [(SalenMe)Zn(OBn)]2 (4). Experimental results show that complexes 2 and 4 efficiently initiate the ring-opening polymerization of l-lactide and rac-lactide in a controlled fashion, yielding polymers with very low polydispersity indexes. Kinetic studies show a second-order dependency on [LA] and a first-order on [2] with magnesium complex 2 as an initiator. While zinc complex 4 is used as an initiator, the polymerization rate has a first order dependency on both [LA] and [4].  相似文献   

3.
Kosaku Tamura  Toshio Masuda 《Polymer》2008,49(21):4494-4501
Novel acetylene monomers substituted with phenylethynylcarbazolyl groups, 3-[(4-octylphenyl)ethynyl]-9-propargylcarbazole (1), 3,6-bis[(4-octylphenyl)ethynyl]-9-propargylcarbazole (2), 9-(4-ethynylphenyl)-3-[(4-octylphenyl)ethynyl]carbazole (3), and 9-(4-ethynylphenyl)-3,6-bis[(4-octylphenyl)ethynyl]carbazole (4) were synthesized, and polymerized with Rh+(nbd)[η6-C6H5B(C6H5)3] and WCl6-n-Bu4Sn catalysts. The corresponding polyacetylenes with number-average molecular weights ranging from 9200 to 94?000 were obtained in 20-98% yields. The IR spectra of the polymers revealed that acetylene polymerization took place at the terminal ethynyl group, while the ethynylene group remained intact. The UV-vis absorption band edge wavelengths of W-based poly(3) and poly(4) were longer than those of the other polymers. W-Based poly(4) emitted fluorescence with the highest quantum yield (41%). Poly(1) exhibited excimer-based fluorescence in dilute solution.  相似文献   

4.
Treatment of sandwich-type mixed (phthalocyaninato)(porphyrinato) metal complex [HEuIII{Pc(α-3-OC5H11)4}{TriBPP(NH2)}] (3) [Pc(α-3-OC5H11)4 = 1,8,15,22-tetrakis(3-pentyloxy)-phthalocyaninate, TriBPP(NH2) = 5,10,15-tris(4-tert-butylphenyl)-20-(4-aminophenyl)porphyrinate] with N-n-butyl-1,6,7,12-tetra(4-tert-butylphenoxyl)perylene-3,4-dicarboxylate anhydride-9,10-dicarboxylate imide (2) in the presence of imidazole in toluene afforded the novel perylene diimide-appended mixed (phthalocyaninato)(porphyrinato) europium(III) double-decker complex (5). Porphyrin-PDI dyad 4 was also obtained by similar method. The electronic absorption spectroscopic and electrochemical properties of PDI-appended double-decker 5 and the model compounds 2, 3, and 4 were studied, the results indicated that there was no considerable ground-state interaction between the double-decker unit and the PDI unit in 5. The fluorescence measurements revealed that the emission of PDI unit was effectively quenched by the double-decker unit, suggesting remarkable intramolecular interaction in 5 under excited state.  相似文献   

5.
Hydrogen-bonded dimers of tetra-urea calix[4]arenes are able to include ferrocenium ions as a guest. Heterodimeric capsules are exclusively formed in 1:1 mixtures of tetra-arylurea calix[4]arene 1 with tetra-tosylurea calix[4]arene 2. Sulfide groups attached via spacers on the urea rim of 1 allow their binding to metal surfaces rendering simultaneously their dissociation more difficult. Thus, the electrochemical response of encapsulated ferrocenium could be studied in a self-assembled monolayer (SAM) in addition to the solution electrochemistry with cyclic voltammetry. The stability of the electrochemically active monolayers was tested after a heat treatment (225 °C for 30 min in N2 atmosphere) and multiple cycling (up to 1200 cycles), which could be required for a possible application as molecular based information storage.  相似文献   

6.
The low efficiency of p-toluenesulfonyl chloride (TsCl) initiator for the polymerization of methyl methacrylate (MMA), when used in conjunction with N,N,N′,N″,N″-pentamethyldiethylenetriamine (PMDETA) and CuBr under atom transfer radical polymerization (ATRP) conditions was investigated. A major by-product in the formation of poly(methyl methacrylate) was identified as N,N-dimethyl-p-toluenesulfonamide (5) and accounted for approximately half of the initiator. Compound 5 was shown to form by the direct reaction of PMDETA and TsCl. In a model experiment equimolar amounts of TsCl, PMDETA and CuBr reacted at 80°C in p-xylene resulted in the formation of 5 and two other unsaturated sulfones 2-methyl-3-[(4-methylphenyl)sulfonyl]-2-propenoic acid methyl ester (6) and 2-[[4-methylphenyl)sulfonyl]methyl]-2-propenoic acid methyl ester (7), formed by the dehydrohalogenation and subsequent isomerization of an intermediate chloro-adduct, 1-(4-methylbenzenesulfonyl)-2-chloro-2-(methyl)methyl propionate (2). Molecular modeling predicted the unsaturated sulfone 7 was thermodynamically more stable than the higher conjugated sulfone 6 and this was confirmed by the isomerization of 6 to 7 at room temperature under mild basic conditions. The absence of 6 and 7 in the polymerization of MMA under ATRP conditions showed that in the early stages of polymerization in the presence of excess MMA, the intermediate chloro-adduct 2 is not formed.  相似文献   

7.
Jinqing Qu  Toshio Masuda 《Polymer》2007,48(22):6491-6500
Pyrene-functionalized chiral methylpropargyl esters, (R)-3-butyn-2-yl-1-pyrenebutyrate [(R)-1], (S)-3-butyn-2-yl-1-pyrenebutyrate [(S)-1], (R)-3-butyn-2-yl-1-pyrenecarboxylate [(R)-2], and 3-butyn-2-yl-1-pyrenecarboxylate [(R,S)-2] were polymerized with (nbd)Rh+[η6-C6H5B(C6H5)3] to obtain the corresponding polymers with moderate molecular weights (Mn: 10?500-66?500) in good yields (82-97%). All the polymers were soluble in CHCl3, CH2Cl2, and THF. The polarimetric and CD spectroscopic data indicated that poly[(R)-1], poly[(S)-1], and poly[(R)-2] existed in a helical structure with predominantly one-handed screw sense in these solvents. The helical structure of poly[(R)-1] and poly[(S)-1] was stable upon heating and addition of MeOH, while that of poly[(R)-2] changed upon MeOH addition. The copolymerization of (R)-1 with (S)-1 was also conducted to obtain the copolymers satisfactorily. Poly[(R)-1], poly[(S)-1], and poly[(R)-2] emitted fluorescence smaller than the corresponding racemic copolymers. The fluorescence intensity was tuned by the addition of MeOH to THF solutions of the polymers.  相似文献   

8.
The synthesis of two novel optically active monomers containing 9-phenylcarbazole moieties, such as (S)-(+)-2-methacryloyloxy-N-[4-(9-carbazolyl)phenyl]succinimide [(S)-(+)-MCPS] and (S)-(+)-3-methacryloyloxy-N-[4-(9-carbazolyl)phenyl]pyrrolidine [(S)-(+)-MCPP], is described. Each monomer has been radically homopolymerized to afford the corresponding optically active polymeric derivatives, which have been fully characterized. Their spectroscopic, thermal and photoconductive properties were compared to those of the new achiral homopolymer poly[N-(2-methacryloyloxyethyl)-N-[4-(9-carbazolyl)phenyl]ethylamine] {poly[MCPE]}, devised as an optically inactive macromolecular model compound, as well as to analogue polymeric derivatives containing side-chain optically active carbazolyl moieties. The chiroptical properties of the chiral polymers are quantitatively higher than in the corresponding monomers. Owing to the substantially stereoirregular structure of the main chain, this suggests that the overall optical activity is mainly due to conformational dissymmetry of the macromolecules. Spectroscopic evidence suggests the presence in all polymeric derivatives of dipole-dipole interactions between the 9-phenylcarbazolyl chromophores, occurring as a consequence of their anchorage to the polymer backbone, which favours their aggregation and justifies their high decomposition temperatures.  相似文献   

9.
A weak electron acceptor, 4,9-bis(5-bromothiophen-2-yl)-2-(2-ethylhexyl)-benzo[f]isoindole-1,3-dione (BIDO) was designed and synthesized. Polymer P1 derived from BIDO and 9,9-dioctylfluorene-2,7-diboronic acid bis(1,3-propanediol) ester by Suzuki cross-coupling reaction has a band gap of 2.41 eV. To expand the absorption range, a different amount of BIDO was copolymerized with a diketopyrrolopyrrole monomer to produce a series of copolymers Pa–c. The optical properties, electrochemical behavior, and energy levels of these four copolymers were investigated. The photovoltaic properties copolymers Pa–c were studied. A photovoltaic device containing Pc and [70]PCBM with a ratio of 1:2 had a power conversion efficiency of 1.17%.  相似文献   

10.
Zhao-Sheng Hou  Kimoom Kim 《Polymer》2006,47(2):742-750
Pseudopolyrotaxanes 3 is synthesized from cucurbituril[6] (CB[6]) and polymer 2 (poly-N1-(4-vinylbenzyl)-1,4-diaminobutane dihydrochloride) in water by simple stirring at room temperature. The monomer 1, polymer 2 and pseudopolyrotaxanes 3 are characterized by 1H NMR, 13C NMR, FT-IR and elemental analysis. In 3, the CB[6] beads are localized on tetramethylene units in side chains of 2, and combine N+ by noncovalent bonds. The degree of threading (number of CB[6] beads per repeat unit) can be controlled from 0 to 1.0 by controlling the amount of CB[6] added. The properties of polymer 2 and pseudopolyrotaxanes 3 are researched by TGA, X-ray powder diffraction (XRD), environment scanning electron microscope (ESEM) and potentiometric titrations. The pseudopolyrotaxanes have higher thermal stability and chain regularity than the parent polymer which are attributed to the bulkiness and the rigidity of the CB[6] threaded. The decomposition temperature and chain regularity of the pseudopolyrotaxanes increase with increasing amount of CB[6] threaded. The effects of salts (NaCl, NaBr or NaI) to pseudopolyrotaxanes are studied by the transmittance with UV-vis, and the results show that NaI is the satisfied precipitant to the pseudopolyrotaxanes. The surface morphologies of pseudopolyrotaxanes 3 observed by ESEM shows a series of spherical particle with different diameter. The results of potentiometric titrations show that the pseudopolyrotaxanes 3 have larger pKav and smaller n than polymer 2.  相似文献   

11.
Chiral polymers P-1 and P-2 were prepared by the polymerization of (R)-3,3′-diiodo-2,2′-bisbutoxy-1,1′-binaphthyl ((R)-M-1) and (S)-3,3′-diiodo-2,2′-bisbutoxy-1,1′-binaphthyl ((S)-M-1) with 2,5-bis[(4-tributylstannyl)phenyl]-1,3,4-oxadiazole (M-2) via Pd(PPh3)4 catalyzed Stille coupling reaction. 1,3,4-Oxadiazole unit not only has high electron affinity, high thermal and oxidative stability, but also serves as a good chromophore. Polymers have strong blue fluorescence due to the efficient energy migration from the extended π-electronic structure of the polymers to the chiral binaphthyl core and can be expected to have potential application in the materials of fluorescent sensors. Circular dichroism (CD) spectra of polymers P-1 and P-2 are almost identical except that they gave opposite signals at each wavelength. The long wavelengths CD effect of P-1 and P-2 can be regarded as the more extended conjugated structure in the repeating unit and a high rigidity of the polymer backbone.  相似文献   

12.
Zhen Li  Qianqian Li  Anjun Qin  Jingui Qin 《Polymer》2005,46(25):11940-11948
A novel series of nonlinear optical (NLO) polysiloxanes with a high density of chromophore moieties based on poly{methyl-[3-(9-indolyl)propyl]siloxane} (PMIPS) were synthesized by a post functional strategy. First, PMIPS (P1) was prepared through hydrosilylation reaction, then P1 is partially formylated by the reaction between P1 and the reagents of dimethylformamide (DMF) and phosphorus oxychloride under the standard Vilsmeier reaction conditions, and these formyl groups with high reactivity are condensed with four predesigned cyanoacetylated chromophores to afford the series of chromophore functionalized polysiloxanes (P3-6). The most special point is the molar concentrations of chromophore moieties are the same in polymers P3-6, which makes it convenient to study the behavior of different chromophores in the polymeric system. The poled films of P3-6 reveal the resonant d33 values in the range of 7.9-55.2 pm/V by second harmonic generation (SHG) measurements.  相似文献   

13.
Melissa A Grunlan 《Polymer》2004,45(8):2517-2523
A series of 1,9-bis[glycidyloxypropyl]pentasiloxanes (IV-VI) were prepared by the platinum catalyzed hydrosilylation of 1,9-dihydridodecamethylpentasiloxane (I), 1,9-dihydrido-3,5,7-tris(3′,3′,3′-trifluoropropyl)heptamethylpentasiloxane (II), and 1,9-dihydrido-3,5,7-tris(1′H,1′H,2′H,2′H-perfluorooctyl)heptamethylpentasiloxane (III) with allyl glycidyl ether. Subsequently, IV-VI were copolymerized with piperazine to form high molecular weight copoly(carbosiloxane)s (VII-IX). The structures of the 1,9-bis[glycidyloxypropyl]penta-siloxanes (IV-VI) and copoly(carbosiloxane)s (VII-IX) were determined by 1H, 13C, 29Si, and 19F NMR as well as IR spectroscopy. The molecular weight distributions (Mw/Mn) of VII-IX have been characterized by gel permeation chromatography and their thermal properties measured by differential scanning calorimetry and thermal gravimetric analysis.  相似文献   

14.
To investigate the difference of the trifluoromethyl (CF3) group and ether group affecting the optical property of fluorinated polyimides (PIs), we prepared 4,4′-bis(4-amino-2-trifluoromethylphenoxy)diphenyl ether (4) with three ether groups and 2,2-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]hexafluoropropane (5) with four CF3 groups with 2-chloro-5-nitrobenzotrifluoride and 4,4′-dihydroxydiphenyl ether or 2,2-bis(4-hydroxyphenol)hexafluoropropane. Two series of organosoluble and light-colored PIs (4a-4c, 5a-5c) were synthesized from 4 and 5 with various aromatic dianhydrides: 3,3,4,4-benzophenonetetracarboxylic dianhydride (BTDA) (a), 4,4-oxydiphthalic anhydride (ODPA) (b), and 4,4-hexafluoroisopropylidenediphthalic anhydride (6FDA) (c), prepared through a typical two-step polymerization method. These PIs were soluble in amide polar solvents and even in less polar solvents. The glass-transition temperatures (Tg) of 4a-5c were 221-249 °C and the 10% weight-loss temperatures were above 530 °C. Their films had cutoff wavelengths between 339 and 399 nm and yellowness index ranges from 1.95 to 42.60. The dielectric constants estimated from the average refractive indices are 2.59-2.93 (1 MHz). In a comparison of the PI series based on 4, 5, and 4,4′-bis(4-amino-2-trifluoromethylphenoxy)biphenyl (6), we found that the CF3 group and ether group on the diamine had almost same effect in lowering the color, but the ether group had better thermal stability. The color intensity of the three PI series was lowered in the following order: 6 > 4 > 5. The PI 5c, synthesized from diamine 5 and dianhydride c, had six CF3 groups in a repeated segment and ether group at the same time, so it exhibited the lightest color among the three series.  相似文献   

15.
The Sonogashira-Hagihara polymerization of 3′,5′-diiodo-N-α-tert-butoxycarbonyl-l-tyrosine methyl ester (1) and 3′,5′-diiodo-N-α-tert-butoxycarbonyl-O-methyl-l-tyrosine methyl ester (2) with para-diethynylbenzene (3) was carried out to obtain optically active poly(m-phenyleneethynylene-p-phenyleneethynylene)s [poly(1) and poly(2)] with Mn’s ranging from 9900 to 15,000 in 80-87% yields. Poly(1) exhibited intense CD signals in DMSO and THF, but did not in CH2Cl2, indicating that it took a predominantly one-handed helical conformation in the former two solvents. On the other hand, there was no evidence for poly(2) to take a helical structure in these solvents. Poly(1) turned the CD sign at 390 nm from plus to minus in DMSO/H2O = 9/1 (v/v) by the addition of NaOH. Alkaline hydrolysis of ester moieties of poly(1) and poly(2) gave the corresponding polymers having carboxy groups [poly(1a) and poly(2a)]. Poly(1a) and poly(2a) increased the CD intensity by the addition of NaOH.  相似文献   

16.
The copolymerization of ethylene with 8-triarylamine (TAA) substituted 1-octene monomers (TAA = triphenylamine (M1), N,N-diphenyl-m-tolylamine (M2), N,N-diphenyl-1-naphthylamine (M3)) using various types of group 4 single-site catalytic systems (Cp2ZrCl2 (C1), rac-EBIZrCl2 (C2), rac-SBIZrCl2 (C3), i-PrCpFluZrCl2 (C4), Me2Si(η5-C5Me4)(η1-N-tBu)TiCl2 (C5)) was investigated to prepare functionalized polyethylene with side-chain TAA groups. The metallocene/methylaluminoxane (MAO) catalytic systems (C1-C4) efficiently lead to the production of high-molecular-weight poly(ethylene-co-M1). While the C4/MAO catalytic system shows the highest comonomer response, the C5/MAO system exhibits the poor compatibility with the M1 comonomer. Copolymerization results of ethylene with M1-M3 using C4/MAO indicate that M1-M3 are well tolerated by both the cationic active species of C4 and MAO cocatalyst, giving rise to the copolymers with high levels of activity and molecular weight. Inspection of the aliphatic region of the 13C NMR spectra of the copolymers (P1-P3) having ca. 11 mol% of M1-M3, respectively, reveals the presence of isolated comonomer units with prevailing [EEMEE] monomer sequences in the polymer chain. UV-vis absorption and PL spectra exhibit an apparent low-energy band broadening for P1 and P2 indicative of intrachain aggregate formation. Whereas P2 and P3 undergo completely reversible one-electron oxidation process, P1 shows relatively poor oxidational stability.  相似文献   

17.
Valentina Alupei 《Polymer》2004,45(7):2111-2117
The free radical polymerization behavior of three norbornadiene derivatives was studied as a function of their structure. The compounds examined were 3-ethoxycarbonyl-tricyclo[3.2.1.02,4]oct-6-ene 1 (liquid), 2-carbethoxybicyclo[2.2.1]-2,5-heptadiene 2 (liquid) and 2-carboxybicyclo[2.2.1]-2,5-heptadiene 3 (solid). They were polymerized in bulk and in benzene solutions. The tricyclic compound 1 was the least reactive monomer whereas the bicyclic derivatives 2 and 3 readily polymerized radically to high conversions. The corresponding polymers were isolated and their structure were determined by means of IR- and NMR spectroscopy. The polymerization of 3-ethoxycarbonyl-tricyclo[3.2.1.02,4]oct-6-ene 1 is supposed to proceed through a simultaneous ring opening-ring closing mechanism. The corresponding polymer poly-1 shows low molecular weights. The polymerization results were compared with those obtained for a conventional solution polymerization of methyl methacrylate.  相似文献   

18.
Optically active, polycarbodiimides 3(a, b & c) with pyridine pendant groups were synthesized using [(R) - 2,2′- binaphthoxy] (di-isopropoxy) titanium(IV) catalyst. The polymers were characterized by 1H and 13C NMR, and IR. Thermal stability of these polymers (up to 162 °C by TGA), allows thermally demanding chemical transformations on their side chains without decomposition. Advantages include fine-tunability of the other pendant group of the carbodiimide monomer. This allows one to optimize the properties of the polymer without undergoing copolymerization or further post-polymerization modifications. Borane (BH3) was coordinated to poly 3 (a & b) to prepare the functional polymers 4 (a & b) respectively. A strong IR signature peak at 2368 cm−1 supports BH3 coordination. Gravimetric analysis indicates 97-99% borane complexation of the pyridine units. In addition, the thermal stability increased to 194 °C in poly 4a is consistent with the incorporation of BH3 to the pendant pyridine of the helical polycarbodiimide 3a. Poly 4 (a & b) can be used as supported reagents and successfully reduced the carbonyl compounds (5 a-e) in moderate to excellent yields (60-100%) and are shown to be efficient, non-volatile, stable, and mild supported-reducing reagents. Upon completion of the reduction reaction, the polymer support was quantitatively recycled as required for a green solid catalyst support.  相似文献   

19.
The reaction of (R,R)-trans-1,2-bis(2,4,6-triisopropylbenzenesulfonamidato)cyclohexane (RRTBSC-H2, 1) with MN[Si(CH3)3] in tetrahydrofuran (THF) produces [(RRTBSC)2M4(THF)4] (2: M = Li, 3: M = Na, 4: M = K). Experimental results show that all three complexes 2-4 are active toward the ring-opening polymerization of l-lactide and compound 2 efficiently catalyzes the polymerization of l-lactide in the presence of a variety of alcohols in a controlled fashion with very narrow polydispersity index. In addition, a variety of biodegradable poly(l-lactide)-block-poly(Nξ-carbobenzyloxy-l-lysine) block copolymers with different ratios have also been synthesized using poly(l-lactide) containing amino chain end (PLLA-NH2) as a macroinitiator.  相似文献   

20.
The solvent extraction of trivalent lanthanoids (Ln3+) by 5,11,17,23-tetra(para-tert-octyl)-25,26,27,28-tetrakis(dimethylphosphinoylmethoxy)calix[4]arene (S), bearing four phosphine oxide donor groups at the lower rim as synergistic agent in combination with a 4-benzoyl-3-methyl-1-phenyl-2-pyrazolin-5-one (HP) in CHCl3 from chloride medium at µ = 0.1 was quantitatively described in the form of LnP3·S complexes. The role of the synergistic agent on the extraction process was discussed. The values of the separation factors have been evaluated. On the basis of the IR and NMR spectra the stoichiometry and the structure of the solid mixed complex of Eu(III) with HP and S were proposed.  相似文献   

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