共查询到20条相似文献,搜索用时 15 毫秒
1.
Cornelia Luca I. Petrariu M. Dima 《Journal of polymer science. Part A, Polymer chemistry》1979,17(12):3879-3888
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
2.
Stela DrÎgan Cornelia Luca I. Petrariu M. Dima 《Journal of polymer science. Part A, Polymer chemistry》1980,18(2):455-465
The reaction of chloromethylated polystyrene with tris(2-hydroxyethyl)amine in N,N-dimethylformamide is described for the conditions to prepare soluble reaction products. The groups of the quaternary ammonium salt, which appear in the first stage of the reaction, transpose to the amino-ether groups. The reaction was followed by elementary analysis, IR and 1H-NMR spectra, and viscosimetric measurements for nondialyzed and dialyzed samples. The presence of the tertiary amine groups on obtained polymers was also shown by titration. The polymers from the reaction of chloromethylated polystyrene with tris(2-hydroxyethyl)amine reacted easily with benzyl chloride. 相似文献
3.
Stela Drgan I. Petrariu M. Dima 《Journal of polymer science. Part A, Polymer chemistry》1972,10(10):3077-3088
The kinetics of the amination of chloromethylated polystyrene with two hydroxyalkylic tertiary amines (1-dimethyl-amino-3-propanol and 1-dimethylamino-2-propanol) in dimethylacetamide and dioxane was studied. The amination of benzyl chloride with the two amines in dimethylacetamide was followed. It was found that the amination of chloromethylated polystyrene is a two-step reaction taking place with different rates. The rate constants k1 and k2 were calculated for the two stages, and a self-accelerating effect of the reaction was noticed. Also, the influence of the position of the hydroxyl group versus the tertiary nitrogen was investigated. The increase of the dielectric constant of the solvent favorably influences the reaction rate. 相似文献
4.
Stela DrÎgan Silvia Ioan I. Petrariu M. Dima 《Journal of polymer science. Part A, Polymer chemistry》1985,23(5):1267-1281
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
5.
Cornelia Luca Stela DrÎgan V. BÎrboiu M. Dima 《Journal of polymer science. Part A, Polymer chemistry》1980,18(2):449-454
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
6.
Stela Drgan I. Petrariu M. Dima 《Journal of polymer science. Part A, Polymer chemistry》1981,19(11):2881-2894
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
7.
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
8.
B. B. Idage S. P. Vernekar N. D. Ghatge 《Journal of polymer science. Part A, Polymer chemistry》1983,21(7):2145-2155
Rates of decomposition of di(3-hydroxybutyl)-2,2′-azobisisobutyrate, di(4-hydroxybutyl)-2,2′-azobisisobutyrate, di(2-hydroxyethyl)-2,2′-azobisisobutyrate, di(2-chloroethyl)-2,2′-azobisisobutyrate, and di(2-hydroxypropyl)-2,2, all of which are useful in the polymerization of butadiene and isoprene, were measured by nitrogen evolution technique at 60, 70, and 80°C, respectively, in each of the three solvents, namely, toluene, dioxane, and N,N-dimethylformamide. The thermal decompositions of these azo compounds in solution were first order, and the Arrhenius equation was used to calculate their activation energies. 相似文献
9.
Well-defined, positively charged, amphiphilic copolymers containing long alkyl side chains were used as stabilizers in the miniemulsion polymerization of styrene. The copolymers were prepared by controlled free-radical copolymerization of styrene and vinyl benzyl chloride using either the reversible addition-fragmentation chain transfer method or TEMPO-mediated polymerization. The benzyl chloride moities were modified by two different long alkyl chain tertiary amines (N,N-dimethyldodecyl amine and N,N-dimethylhexadecyl amine) to yield the amphiphilic copolymers with vinylbenzyl dimethyl alkyl ammonium chloride units. Owing to their high structural quality, only a small amount of these copolymers was required to stabilize the latex particles (0.5–2 wt% vs styrene). Moreover, in the absence of any hydrophobic agent, the amphiphilic comblike copolymer preserved the colloidal stability of both the initial liquid miniemulsion and the final latex. Ill-defined, analogous copolymers were synthesized by conventional free-radical polymerization and in comparison, exhibited poor stabilization properties. 相似文献
10.
Masao Tomoi Satoru Ishigaki Yasushi Arita Hiroshi Kakiuchi 《Journal of polymer science. Part A, Polymer chemistry》1988,26(8):2251-2261
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
11.
Ghezalla Tabak Thi-Nhn Pham Guy Levesque Rachid Haraoubia 《Journal of polymer science. Part A, Polymer chemistry》1998,36(1):117-127
Thioamide groups were introduced into polystyrenes by the Friedel–Crafts reaction, with phenyl isothiocyanate in nitromethane solution, in the presence of anhydrous aluminium chloride. Free radical copolymerization of 4-vinyl dithiobenzoate with styrene followed by low-temperature solution condensation reactions, with excess of amines in N,N-dimethylformamide, offered another synthetic route to (co)polymers containing thioamine groups in the side chains without crosslinking. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 117–127, 1998 相似文献
12.
Alberto Hernandez Gainza 《国际化学动力学杂志》2004,36(9):500-509
Halogenated hydrocarbon solvents, SolvCl, (dichloromethane, chloroform, and 1,2‐dichloroethane) react with various types of tertiary amines, A, such as tri‐n‐buthylamine, tropane derivatives (tropine and atropine) and quinine generating a quaternary ammonium salt, N‐halogenalkylammonium chloride (SolvA+Cl?). Some tertiary amines, as well as secondary and primary amines, cannot react with these solvents. This reaction has been detected and studied by both conductivity and visible spectrophotometry measures—the latter after adding a small quantity of a dye, such as bromocresol green (BCGH2), bromophenol blue (BPBH2), or tetrabromophenolphthaleinethyl ester (TBPEH). Both study methods permit the determination of the kinetic parameters, and they are in good agreement. The monoprotic TBPEH is the dye of the simplest mechanism, useful to study kinetics of amines of uncertain behavior as quinine, while BPBH2 is the best dye for quantitative determinations. Kinetics for this reaction are of first order for both amine, A, and solvent, SolvCl; activation energy, Ea, and frequency factor are also determined. Rate constants increase with the amine basicity and with a reduction in the number of the halogen atoms present in the solvent. This reaction is slow but not negligible and must be considered a side reaction of these universally used solvents. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36:500–509, 2004 相似文献
13.
Abdullah Aydogan 《Supramolecular chemistry》2016,28(1-2):117-124
A polystyrene with pendant calix[4]pyrroles was prepared via ‘click reaction’ strategy. First, a poly(styrene-co-chloromethylstyrene) with approximately 12% of chloro groups was prepared by conventional free radical polymerisation. The chloro groups were then converted to azido groups using NaN3 in N,N-dimethylformamide. An alkyne-functionalised calix[4]pyrrole was then coupled to the azido-functionalised polystyrene by click chemistry with high efficiency. The resulting polystyrene with pendant calix[4]pyrroles was used to extract fluoride and chloride anions (as their tetrabutylammonium salts) from their aqueous solutions to organic media. 相似文献
14.
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
15.
《Tetrahedron: Asymmetry》2007,18(13):1511-1516
It is shown that lyotropic liquid crystal mixtures made of poly-γ-benzyl-l-glutamate (PBLG) dissolved in N,N-dimethylformamide (DMF) are efficient anisotropic NMR solvents to distinguish the enantiomers of chiral amines through the effects of the differential ordering of enantiomers. This type of solvent overcomes problems often encountered when dissolving amines into the more conventional PBLG/CHCl3 or PBLG/CH2Cl2 liquid crystals. Furthermore, it is shown that perdeuterobenzyl chloride is an excellent achiral deuterated derivatizing agent for enantiomeric excess measurements of chiral amines in conjunction with the PBLG/DMF solvent. 相似文献
16.
17.
Polyaniline coated on particles of celite is used as support to load palladium catalyst. This heterogenized Celite?PANI?Pd system, is used as an efficient catalyst for chemoselective hydrogenation reactions. The catalyst is characterized by usual spectral, analytical techniques and studied for hydrogenation reactions at ambient conditions. The mild reaction conditions allow the control over the reactions and excellent selectivity is achieved in number of conversions. Hydrogenation of a carbon–carbon double bond was favored over other polar π‐bond systems, while labile functional groups such as benzyl ether, benzyl esters, cyano, nitro and halogen remained unaffected. Primary amines were converted to N,N‐dimethyl amines with formaldehyde, the double bond of coumarin was selectively hydrogenated without opening of the lactone functionality. 相似文献
18.
Ring‐opening polymerization of six‐membered cyclic carbonates initiated by ethanol amine derivatives and their application to protonated or quaternary ammonium salt‐functionalized polycarbonate films 下载免费PDF全文
Hiroyuki Matsukizono Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2016,54(4):487-497
Ring‐opening polymerization (ROP) of monofunctional neopentylglycol carbonate (NPGC) with or without bifunctional di(trimethylolpropane) carbonate (DTMPC), which are derived from available corresponding alcohols, affords linear polycarbonates or covalently‐linked polycarbonate networks, respectively. A series of available ethanol amine derivatives having the different numbers of 2‐hydroxylethyl arms (N,N,N’,N’‐tetrakis(2‐hydroxyethyl)ethylenediamine, triethanolamine, N‐methyldiethanolamine or N,N‐dimethylethanolamine) initiates the ROP of NPGC to afford star‐shaped, telechelic, or linear polycarbonates bearing tertiary amines with well‐controlled molecular weights and relatively narrow polydispersities Furthermore, the copolymerization of NPGC and DTMPC in the presence of these initiators readily gives tertiary amine‐modified polycarbonate films with well transparency and flexibility. These amino groups are easily converted to ammonium salts by protonation with acids, while the quaternization with benzyl bromide is strongly affected by the steric hindrance of these amines. N‐Methyldiethanolamine or N,N‐dimethylethanolamine residues in these films react easily with benzyl bromide to give quaternary ammonium salt‐functionalized films. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 487–497 相似文献
19.
Shaio-Wen Wong Kurt C. Frisch 《Journal of polymer science. Part A, Polymer chemistry》1986,24(11):2867-2875
An analytical method based on high performance liquid chromatography (HPLC) has been developed to investigate the competing isocyanate reactions under the influence of various catalysts. The kinetics of the model reaction between phenyl isocyanate and n-butanol was studied in acetonitrile at 50°C. Effects of various catalysts such as an organotin compound, dibutyltin dilaurate, and tertiary amines, 1,4-diazabicyclo-(2,2,2)octane,N,N′,N″-pentamethyldiprophylene triamine,N,N′N″-tris(3-dimethyl-aminopropyl)-3-hexahydrotriazine, and N,N,N′-trimethylaminoethyl-ethanolamine on the reaction rate and the formation of reaction products were investigated. The reactions were followed by determining the NCO disappearance using the standard di-n-butylamine back-titration method as well as measuring the formation of various reaction products using the HPLC method. The relative specificity of a catalyst in isocyanate reactions can thus be determined from the profile of the model reaction which depends upon the structure of the catalyst employed. 相似文献
20.
B. N. Misra P. S. Chandel 《Journal of polymer science. Part A, Polymer chemistry》1980,18(4):1171-1176
Grafting of poly(methyl acrylate) onto wool has been carried out in an aqueous medium at 45 ± 1°C by using ceric ammonium nitrate (CAN) in the presence of triethylamine, diethylamine, n-butylamine, triethanolamine, and N,N-dimethylaniline. The percentage of grafting varied with the nature and concentrations of the amines. Reactivity of the different amines toward grafting reactions followed the order: triethylamine > diethylamine > n-butylamine > triethanolamine ≥ N,N-dimethylaniline. In the presence of N,N-dimethylaniline grafting did not occur. An attempt has been made to explain the observed reactivity of Ce4+ in various amine systems in graft copolymerization reactions. 相似文献