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1.
The reaction of chloromethylated polystyrene with methyl(2- hydroxyethyl)amine and butyle (2-hydroxyethyl)amine was studied kinetically. The reaction of benzyl chloride with these amines was also investigated for comparison. N,N-dimethylformamide and dioxane were used as solvents. The reactions of benzyl chloride with the two amines in these solvents took place according to normal kinetics of the second order. Reaction kinetics depend on the nature of the amine and solvent in Chloromethylated polystyrene reactions. In dioxane the self-accelerating effect of the reaction for β ? 0.5 is apparent. Steric hindrance of the reaction, beginning with a conversion degree of about 75%, wss observed for butyl(2-hydroxyethyl)amine in N,N-dimethylformamide. This self-accelerating effect is observed in dioxane at the same reaction degree. The activation energies and frequency factors were calculated for the amination of benzyl chloride and chloromethylated polystyrene with the two amines in N,N-dimethylformamide and dioxane.  相似文献   

2.
A multifunctional crosslinked polymer resulted from a chloromethylated polystyrene reaction with tris(2-hydroxyethyl)amine. A benzyl chloride reaction (chosen as a structural unit model) with tris(2-hydroxyethyl)amine was investigated to explain the reasons for the crosslinking. Amino-ethers and tris(2-hydroxyethyl)amine hydrochloride in addition to ammonium quaternary salt were isolated from this reaction. The formation of amino-ethers proved that an ammonium quaternary salt rearrangement also takes place during the quaternization reaction. This rearrangement leads to chloromethylated polystyrene during its reaction with tris(2-hydroxyethyl)amine.  相似文献   

3.
The macromolecular chain conformational state during the amination of chloromethylated polystyrene (CMPS) with two aliphatic amines, namely methyl(2-hydroxyethyl)amine (MHEA) and N,N-dimethyl(2-hydroxypropyl)amine (DM2HPA), has been studied. Viscosimetric and light scattering measurements were performed during reactions in binary solvent mixtures. The observed kinetic deviations have been related with the conformational transformations of the macromolecular chain.  相似文献   

4.
The amination kinetics of benzyl chloride and chloromethylated polystyrene with three tertiary amines were studied: N-2-hydroxyethyl-dimethylamine, N,N-bis(2-hydroxyethyl)-methylamine, and triethylamine in N,N-dimethylformamide. The amination of chloromethylated polystyrene takes place with two reaction rate constants K1 and K2. K2 is higher than K1; hence there is a self-accelerating effect. This phenomenon is due to the influence of the positive electrostatic field of the macroion chain on amines that are nucleophilic reactants. The magnitude of the self-accelerating effect given by the K2/K1 ratio depends on the substituent volume of the nitrogen atom of the amine molecule.  相似文献   

5.
The amination reactions of chloromethylated polystyrene with N,N-dimethyldodecylamine, N,N-dimethyltetradecylamine, and N,N-dimethylhexadecylamine were studied. The physical properties, particularly the solubility properties of the resulting polymers, are influenced by the hydrophobic properties of the long alkyl chain on the N+ atoms. The main factor that influences the kinetics of the reactions is the polymersolvent interaction parameter.  相似文献   

6.
Reaction of phenyltrifluorosilane, diphenyldifluorosilane, and methylphenyldifluorosilane with bis(2-hydroxyethyl)amine, methyl-bis(2-hydroxyethyl)amine, methyl-bis(2-trimethylsiloxyethyl)amine, leads to 1,3-dioxa-6-aza-2-silacyclooctane derivatives, (N → Si) quasisilatranes: 1,1-difluoroquasisilatrane, 1-phenyl-1-fluoro-5-methylquasisilatrane, or 1-methyl-1-fluoroquasisilatrane, containing the donor-acceptor bond N → Si and pentacoordinate silicon atom. 1-Phenylsilatrane was found to be the product of the reaction of phenyltrifluorosilane with tris(2-trimethylsiloxyethyl)amine, whereas with tris(2-hydroxyethyl)amine 1-phenylsilatrane and 1-fluorosilatrane were formed in the molar ratio of 3:1. The structure of the synthesized compounds was proved by 1H, 13C, 15N, 19F, 29Si NMR and IR spectroscopy.  相似文献   

7.
It was established that linear polymers with quaternary ammonium groups are obtained by the reaction of chloromethylated polystyrene (CMPS) with hydroxyalkylic tertiary amines when the amines contain one or two hydroxyl groups, and that crosslinked polymers are obtained with aminoether groups when the amines have three hydroxyl groups, i.e., tris(2-hydroxyethy1)amine. The aminoether units appear by intramolecular rearrangement of quaternary ammonium structural units. Kinetic studies on the synthesis of polymers with quaternary ammonium groups from CMPS, poly(N,N-dimethylamino-ethylmethacrylate), and poly(N,N-dimethylaminopropylacrylamide), were performed. The main factors which influence the kinetics of reactions are steric hindrance of near neighboring groups, hydrophilic effect for hydroxyalkylamines and polymer-solvent interaction.  相似文献   

8.
Reaction of tetrafluorosilane with tris(2-hydroxyethyl)-and tris(2-trimethylsiloxyethyl)amine results in formation of 1-fluorosilatrane and fluorosilatrane in 75 and 53% yield, respectively. Reaction of tetrafluorosilane with bis(2-trimethylsiloxyethyl)amine and its N-methyl derivative leads to the hitherto unknown 1,1-difluoroquasisilatranes (N → Si) F2Si(OCH2CH2)2NR (R = H, Me) containing donor-acceptor bond N → Si and pentacoordinate silicon atom. The structure of the synthesized compounds was proved by 1H, 13C, 15N, 19F, 29Si NMR and IR spectroscopy.  相似文献   

9.
Poly[(4-N-ethylene-N-ethylamino)-α-cyanocinnamate] was prepared by solution esterification of (4-N-ethyl-N-(2-hydroxyethyl) amino)-α-Cyanocinnamic acid and by melt transesterification of ethyl (4-N-ethyl-N-(2-hydroxyethyl) amino)-α-cyanocinnamate. The melt transesterification generally yielded polymer with a number-average molecular weight of about 10,200 by gel permeation chromatography (GPC) versus polystyrene standards. The polymer was found to be amorphous with a glass transition temperature of about 103°C by differential scanning calorimetry (DSC). The solution esterification generally gave a polymer with a number-average molecular weight of about 2200 by GPC versus polystyrene standards. This polymer was found to have a glass transition temperature varying between 60 and 90°C by DSC. The infrared (IR) spectrum of the polymer made from both methods were analyzed in detail. The 1H- and 13C-NMR spectra of the meltsynthesized ethyl cinnamate derivative polymer are consistent with the reported structure.  相似文献   

10.
Crosslinked chloromethylated polystyrene ( 1 ) and crosslinked copoly(styrene-p-nitro-phenylacrylate) ( 3 ) readily reacted with 1,1-dimethylhydrazine, but the course of the reaction was strongly dependent on the structure of the backbone. Monofunctionalization was observed with chloromethylated polystyrene ( 1 ) giving the 1,1,1-dimethylhydrazinium chloride derivative ( 2 ), while high degree of additional crosslinking took place with crosslinked copoly(styrene-p-nitrophenylacrylate) ( 3 ), and additional crosslinking was also observed in functionalization with N-aminopiperidine and N-aminomorpholine. The additional crosslinking suggested a higher backbone mobility in acrylate beads ( 3 ) compared to chloromethylated polystyrene ( 1 ). The type of transformation and the degree of additional crosslinking also depended on the starting crosslinking of copoly(styrene-p-nitrophenylacrylate) ( 3; 3a , 2% DVB; 3b , 4% DVB; 3c , 10% DVB). Replacement of p-nitrophenol groups in copoly(styrene-p-nitrophenylacrylate) ( 3 ) with hydrazino units resulted in enhanced swelling abilities of the hydrazine derivatives ( 4, 5, 6 ) in methanol, dimethylformamide, and chloroform, while formation of the hydrazinium chloride derivative ( 2 ) from chloromethylated polystyrene ( 1 ) caused enhancement of swelling in methanol but diminished it in toluene. The degree of crosslinking of copoly(styrene-p-nitrophenylacrylate) ( 3 ) also influenced the swelling abilities of 3 and its hydrazino derivatives, being higher with 2% cross-linked resins and lower with 4% and 10% crosslinked resins. © 1996 John Wiley & Sons, Inc.  相似文献   

11.
Schiff base-functionalized chloromethylated polystyrenes, PS-[Ae-Eol] (I), PS-[Hy-Eda] (II) and PS-[HyP-Eda] (III), were synthesized by reacting 2-(2-aminoethoxy)ethanol (Ae-Eol), N-(2-hydroxyethyl)ethylenediamine (Hy-Eda), and N-(2-hydroxpropyl)ethylenediamine (HyP-Eda) with oxidized chloromethylated polystyrene. Oxidized chloromethylated polystyrene (PS-CHO) was prepared by oxidation of chloromethylated polystyrene (PS) with sodium bicarbonate in DMSO. By reacting DMSO solution of [VO(acac)2] with polymer-anchored Schiff base ligands I, II, and III, vanadium(IV) complexes PS-[VIVO(Ae-Eol)] (1), PS-[VIVO(Hy-Eda)] (2), and PS-[VIVO(HyP-Eda)] (3) were prepared. Structure and bonding of I, II, and III as well as corresponding vanadium complexes 1, 2, and 3 were confirmed by FT-IR, UV–vis spectroscopy, SEM, EDX, AAS, TGA, EPR, etc. Polymer-anchored vanadium(IV) complexes 1, 2, and 3 show, efficient catalysis toward oxidation of styrene, cyclohexene, allylbenzene, and cis-cyclooctene in the presence of hydrogen peroxide. Optimized reaction conditions for the oxidation of these alkenes was achieved by changing various reaction parameters (like amount of catalyst, amount of oxidizing agent, volume of solvent, etc.). Polymer-grafted 1, 2, and 3 can be reused multiple times without depletion of their activity.  相似文献   

12.
Polystyrene-bound 4-(1-pyrrolidino)pyridine moieties were prepared by the reaction of chloromethylated polystyrene resins with pyrrolidinopyridine derivatives containing hydroxyl groups. The supported amines were effective catalysts for acylations of tert-alcohols or enols, acylrearrangements, and diester synthesis from epoxides and anhydrides. Some of the low ring-substituted (8–15%) catalysts exhibited high activity comparable to that of 4-(N,N-dimethylamino)pyridine, though the activity was a little lower than that of 4-(1-pyrrolidino)pyridine. The recovered catalysts can be re-used, except for acyl rearrangements, without significant decrease in activity.  相似文献   

13.
The conversion of naphthalene, anthracene, and phenanthrene to polymeric material via Friedel-Crafts chemistry was investigated. Synthesis of the polymers was accomplished by: (1) self-condensation of the chloromethylated aromatic substrate in the presence of AlCl3 or SnCl4 or (2) treatment with chloromethyl ethyl ether (CMEE) and SnCl4, producing the chloromethylated substrate in situ, followed by self-condensation polymerization. Soluble or insoluble polymers were preferentially produced by varying the stoichiometry, time, or temperature of the reaction. The resulting polymers consisted of the polycyclic aromatic nuclei bridged by methylene groups. The regiochemistry of the polymer linkages was determined through the use of IR, 1H- and 13C-NMR. The polymers showed relatively high thermal and thermo-oxidative stabilities (380–495°C). © 1992 John Wiley & Sons, Inc.  相似文献   

14.
N, N-di (2-hydroxyethyl)-3-aminopropionic acid (M3) was synthesized and used for the preparation of a series of polyesters having amino acid moieties in the main chain and carboxyl groups as the side group. Polycondensation of M3 , diols, bisphenol A, and isophthaloyl dichloride were performed in the presence of tertiary amine by solution and interfacial methods. Molecular weights of the polymers obtained by the solution method were not high, because oligomers produced at the early stage of reaction are ionized by H+ ions from the by-product, and become nonreactive triethylamine hydrochloride. Polymers with high M?w (1–10 × 104) were obtained in a high yield by organic/organic two-phase interfacial polycondensation using DMAc and n-heptane as solvents. The combined nucleophilic and basic complex catalytic action of N, N, N′, N′-tetramethyl ethyiene diamine (TEMED) is suggested for the present organic phase/organic phase interfacial polycondensation. This method can be applied for the preparation of novel functional polyesters. © 1994 John Wiley & Sons, Inc.  相似文献   

15.
Reaction of tris(2-hydroxyethyl)amine hydrochloride Cl N+H(CH2CH2OH)3 with zinc diacetate and bis(2-methylphenoxy)acetate in the molar ratio 2: 1 results in complexes 2[Cl N+H(CH2CH2OH)3]· Zn (OCOR)2 (I, II) R= Me (I), 2-MeC6H4OCH2 (II), which contain two protatrane cations linked with zinc diacylate by two coordination bonds HO → Zn. Complexes I and II are also formed by the reaction of the corresponding tris(2-hydroxyethyl)amine hydrochloride acylate RCOON+H(CH2CH2OH)3 with ZnCl2. The structure of complexes I, II is proved by elemental analysis, IR and 1H, 13C, 15N NMR spectroscopy.  相似文献   

16.
Novel electrochromic polymers were prepared by the click postfunctionalization of poly(4‐azidomethylstyrene) with alkyne‐containing aromatic amine units in the presence of Cu(I) catalysts. Two kinds of aromatic amine units, tris(4‐alkoxyphenyl)amine and N,N,N′,N′‐tetraphenyl‐p‐phenylenediamine, were introduced into polystyrene side chains, which were completely characterized by gel permeation chromatography–multiangle light scattering, nuclear magnetic resonance, and infrared spectroscopies, and elemental analysis. Thermal analyses demonstrated the high stability with the decomposition temperatures exceeding 300 °C even after postfunctionalization. The UV–vis absorption spectra of the polymer thin films revealed negligible absorption in the visible region, as reasonably confirmed by visual observation. The polymer thin films were prepared by spray‐coating on an indium tin oxide‐coated glass plate. Cyclic voltammograms of these films exhibited anodic peaks ascribed to the oxidation of the side‐chain aromatic amine moieties. The tris(4‐alkoxyphenyl)amine unit displayed one‐step oxidation at 0.287 V (vs. Ag/AgCl), while the N,N,N′,N′‐tetraphenyl‐p‐phenylenediamine unit showed two‐step oxidations at 0.297 and 0.641 V. These oxidation processes produced new colors of the polymer films. The former triarylamine‐based chromophore provided a blue color after the oxidation, while the latter phenylenediamine‐based chromophore showed a potentially controlled green and dark blue colors. The reversibility and switching behaviors of these color changes were also comprehensively investigated. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

17.
Thermoreversible polymeric biomaterials are finding increased acceptance in tissue engineering applications. One drawback of the polymers is their synthetic nature, which does not allow direct interaction of mammalian cells with the polymers. This limitation may be alleviated by grafting arginine–glycine–aspartic acid (RGD) containing peptides onto the polymer backbone to facilitate interactions with cell‐surface integrins. Toward this goal, N‐isopropylacrylamide (NiPAM)‐based thermoreversible polymers containing amine‐reactive N‐acryloxysuccinimide (NASI) groups were synthesized. Conjugation of RGD‐containing peptides to polymers was demonstrated with 1H NMR spectroscopy and reverse‐phase high‐pressure liquid chromatography. The conjugation reaction was optimal at 4 °C and pH of 8.0, and increased with the increasing NASI content of polymers. With a peptide grafting ratio of 0.25 mol %, there was no significant change in the lower critical solution temperature of the polymers. Finally, the NASI‐containing polymers, cast as films, on tissue culture polystyrene, were shown to conjugate to RGD‐containing peptides and support C2C12 cell attachment. We conclude that NASI‐containing thermoreversible polymers are amenable for grafting biomimetic peptides to impart cell adhesiveness to the polymers. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3989–4000, 2003  相似文献   

18.

The previously unknown ability of Zitrimin, the complex of tris(2-hydroxyethyl)amine with zinc(ii) bis(2-methylphenoxyacetate), to affect the activity of acid lipase of the aortic intima was studied. Daily administration of an aqueous solution of the tris(2-hydroxyethyl)amine complex with zinc bis(2-methylphenoxyacetate) in a dose of 10 mg kg?1 for 3 months to rabbilts with experimental atherosclerosis was found to decrease the cholesterol and total lipid levels in the aortic tissue and to decrease the degree of aortic damage with atherosclerotic plaques. According to the results of enzymatic analysis, development of atherosclerosis is accompanied by 68% increase in the activity of acid lipase in the intima of the aorta compared to the control.

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19.
Dibenzo‐24‐crown‐8‐terminated polystyrene ( 5 ) was chain extended to “dimeric” 8 by pseudorotaxane formation with a ditopic guest, α,ω‐bis[p‐(N‐benzylammoniomethyl)phenoxy]heptane bis(hexafluorophosphate) ( 7 ). The three‐armed star polymer 11 was similarly formed by complexation of the dibenzo‐24‐crown‐8‐terminated polystyrene ( 5 ) with a tritopic secondary ammonium salt, 1,3,5‐tris[p‐(benzylammoniomethyl)phenyl]benzene tris(hexafluorophosphate) ( 10 ). Another three‐armed star polymer 13 was self‐assembled from dibenzo‐24‐crown‐8‐terminated polystyrene ( 5 ) and a tetratopic paraquat compound, 1,2,4,5‐tetrakis{pN‐[(N′‐methyl‐4,4′‐bipyridinium)methylphenyl]}benzene octakis(hexafluorophosphate) ( 12 ). The above chain extension and star polymer formation processes seemed to be cooperative; that is, the second and third complexation steps proceed with stepwise higher efficiencies than statistically expected. Dibenzo‐24‐crown‐8‐terminated polystyrene ( 5 ) was chain extended with secondary ammonium terminated polystyrene 14 , forming 16 , and also self‐assembled with a secondary ammonium ion terminated polyisoprene 15 to form supramolecular block copolymer 17 . These processes were examined by NMR, mass spectrometry and viscometery. Thus, although binding in these systems is not particularly strong (association constants <104 M?1), these examples provide proof‐of‐principle that pseudorotaxane formation is a viable concept for chain extension and self‐assembly of novel types of block copolymers and star polymers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3518–3543, 2009  相似文献   

20.
The reaction kinetics of halogenated compounds with tertiary amine groups attached at an acrylic macromolecular chain have ben studied. Three acrylic polymers were used. Two of them have mainly a structural unit of N, N-dimethylaminopropylacrylamide and the third is poly(N,N-dimethylaminoethylmethacrylate). Dimethylformamide, dimethylacetamide, and dimethylsulfoxide (DMSO) were used as dipolar aprotic solvents. Benzyl chloride and allyl chloride were considered as halogenated compounds with increased reactivity. The reaction kinetics depend on the polymer and halogenated-compound structures as well as the nature of the solvent. In the most of the cases the reactions carried out on polymers are accompanied by self-accelerating processes, with the exception of DMSO, which obviously has normal second-order kinetics. The reaction of polymers containing units of N,N-dimethylaminopropylacrylamide are compared with one having a low molecular weight, for instance N,N′-bis(3-dimethylaminopropyl)glutaramide.  相似文献   

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