摘要:

AbstractThe study concerns the potentiometric behaviour of statistical copolymers of 2‐dimethylaminoethyl methacrylate with 2‐hydroxyethyl methacrylate, acrylamide, methacrylamide, 2‐methacryloyloxyethyltrimethylammonium methylsulfate, and of copolymers arising by the partial quaternization of poly(2‐dimethylaminoethyl methacrylate) with methyl iodide in various water‐ethanolic solutions. The potentiometric properties of poly(4‐dimethylaminobutyl methacrylate) and poly(6‐dimethylaminohexyl methacrylate) are also reported. The course of modified titration curves and the differences between pK0values of copolymers and pKvalues of low‐molecular weight model compounds are discussed. Side chains of copolymers of 2‐dimethylaminoethyl methacrylate have a cyclic conformation (similarly to the homopolymer); the carbonyl and amine group interact with each other. Copolymers formed by the partial quaternization of poly(2‐dimethylaminoethyl methacrylate) with methyl iodide in a water‐ethanolic medium (Menshutkin's reaction) have a block structure, which suggests a zip mechanism of the qu

ISSN:0025-116X    

DOI:10.1002/macp.1987.021880201

出版商:Hüthig&Wepf Verlag    

年代:1987

数据来源: WILEY

摘要:

AbstractThe kinetics of the nonactivated anionic polymerization of 2‐pyrrolidone (PD) initiated with the potassium salt of 2‐pyrrolidone (KPD) and anionic polymerizations of PD accelerated with CO2and 1‐(1‐pyrrolin‐2‐yl)‐2‐pyrrolidone or activated with 1‐benzoyl‐2‐pyrrolidone and 1‐acetyl‐2‐pyrrolidone were followed near the ceiling temperature (limit temp.T1) and discussed. The values ofT1were extrapolated from the data obtained for the given initiation systems. The dependence ofT1on the concentration of the initiation s

ISSN:0025-116X    

DOI:10.1002/macp.1987.021880202

出版商:Hüthig&Wepf Verlag    

年代:1987

数据来源: WILEY

摘要:

AbstractDrug carriers were prepared by combining oligopeptidic sequences with synthetic polymeric chains. Soluble copolymers ofN‐(2‐hydroxypropyl)methacrylamide (HPMA) were synthesized containing oligopeptidic side chains terminating in a drug model (p‐nitroaniline). The susceptibility of these oligopeptidic sequences to degradation on incubation with lysosomal enzymes and human serum was evaluated by monitoring thep‐nitroaniline liberation. It was shown that the drug model can be attached to the polymer carrier by means of an oligopeptidic spacer stable in blood serum and degradable after the polymer has been in contact with intracellular lysosomal enzymes. The studied polymer carriers were used for binding an anticancer drug, bis(2‐chloroet

ISSN:0025-116X    

DOI:10.1002/macp.1987.021880203

出版商:Hüthig&Wepf Verlag    

年代:1987

数据来源: WILEY

摘要:

Abstract20‐(Methacryloyloxy)icosyl 2‐(trimethylammonio)ethyl phosphate (4a) and 32‐(methacryloyloxy)dotriacontyl 2‐(trimethylammonio)ethyl phosphate (4b) were prepared and characterized. These monomers were polymerized and the properties of the resultant polymers are de

ISSN:0025-116X    

DOI:10.1002/macp.1987.021880204

出版商:Hüthig&Wepf Verlag    

年代:1987

数据来源: WILEY

摘要:

AbstractThe anionic polymerizations of 2,2,2‐trifluoroethyl acrylate (1a), 2,2,2‐trifluoroethyl methacrylate (1b), 2,2,2‐trifluoro‐1‐trifluoromethylethyl acrylate (2a), and 2,2,2‐trifluoro‐1‐trifluoromethylethyl methacrylate (2b) were examined with triethylaluminium and diethylaluminium active methylene chelate compounds as initiators.2bwas polymerized with triethylaluminium. Diethyl(ethyl cyanoacetato)aluminium was found to produce polymers of1aand1b. Diethyl(acetylacetonato)aluminium and diethyl (dimethyl malonato)aluminium, however, show low reactivity towards these four monomers. The resulting polymers show unimodal molecular weight distribution with number‐average molecular weights of 104−105, measured by GPC. The initiation reaction and the copolymerization reactivity with styrene support the anionic polym

ISSN:0025-116X    

DOI:10.1002/macp.1987.021880205

出版商:Hüthig&Wepf Verlag    

年代:1987

数据来源: WILEY

摘要:

AbstractCyclocopolymerizations of maleic anhydride (1) with 1,5‐hexadiene (2a) and 2,5‐dimethyl‐1,5‐hexadiene (2b) were compared with those of1with 1,4‐dienes which have been reported to yield highly cyclized polymers following a bimolecular alternating inter‐intramolecular mechanism. The mole ratio of monomeric units of1to those of the dienes in the copolymers was almost 2:1, though it changed slightly with the monomer composition in the feeds. Although the fundamental aspect of the copolymerization of1with 1,5‐dienes was found to be similar to that with 1,4‐dienes, the structures of the copolymers are different from those obtained with 1,4‐dienes in that not only pendant double bonds, but also other unsaturations were detected. The unsaturations were formed by combination of propagating radicals with the allyl radical, which is considered to be formed by hydrogen abstraction from the penultimate hexenyl group. A mechanism is proposed to explain the degree of cyclization and the copo

ISSN:0025-116X    

DOI:10.1002/macp.1987.021880206

出版商:Hüthig&Wepf Verlag    

年代:1987

数据来源: WILEY

摘要:

AbstractPolymerizableN2‐(4‐chloro‐2‐methylphenyl)‐N1‐methylformamidine derivatives of (N‐demethyl‐chlordimeform) (2) were prepared, bearing either 4‐vinylbenzyloxy‐ or 2‐methacryloyloxyethoxycarbamoyl groups (5and7), and in addition, a triazatriphosphorine derivartive of2(8). The carbamoyl groups and the P‐N linkages in the monomers, respectively, were specifically designed to release the insecticide2under the particular microenvironmental conditions on cotton leaves by hydrolytic cleaveage, triggered by the pH 8–10 of the leaf surface. Biossaying experiments using larvae of the Egyptian Cotton Leafworm (Spodoptera littoralis) on cotton plants confirmed methacrylate7as the only compound with sufficient bioactivity. Corresponding homo‐ and copolymers of7, containing covalently bound pendent moieties of2, showed advantageous physiochemical properties with regard to improved efficiency and reduced environmental and handling risks in conventional foliar applications. The biological data suggest that the release rates of the active agent from the polymers vary significantly, depending on the hydrophilicity of the comonomers and t

ISSN:0025-116X    

DOI:10.1002/macp.1987.021880207

出版商:Hüthig&Wepf Verlag    

年代:1987

数据来源: WILEY

摘要:

AbstractThe fluorescence spectra of poly[N‐(2‐hydroxypropyl)methacrylamide] (poly[1‐(2‐hydroxypropylaminocarbonyl)‐1‐methylethylene]) with covalently bonded luminiscent markers (2‐amino‐1, 3‐di(2‐naphthyl)propane (ADNP)) dissolved in methanol were measured over the temperature range 190–290 K. The effect of the spacer length on intramolecular excimer formation in ADNP was investigated. The ratio of the fluorescence intensities of the dimerIDand the monomerIMfollows an Arrhenius temperature dependence in the temperature range 190–250 K with an activation energy independent of the spacer length. The numerical value ofID/IMat constant temperature increased with increasing spacer length reaching quickly a limiting value. The effect is explained by increasing hindrance to intramolecular excimer formation which is due—particularly for the shortest spacers—to increased steric interactions of the ma

ISSN:0025-116X    

DOI:10.1002/macp.1987.021880208

出版商:Hüthig&Wepf Verlag    

年代:1987

数据来源: WILEY

摘要:

AbstractA computer simulation of the kinetics of the amine salt initiated lactam polymerization was carried out using an extended kinetic model. In the reaction scheme the formation and relatively fast two‐way reaction of a tetrahedral intermediate, as well as the role of the acid in its formation were incorporated. On the basis of the extended kinetic model the calculated lactam conversion and the concentration ofN‐terminal groups, respectively, have been found to be in good agreement with the experimental values for both the amine salt initiated and the hydrolytic lactam polymerization. The numerical values of rate and equilibrium constants are gi

ISSN:0025-116X    

DOI:10.1002/macp.1987.021880209

出版商:Hüthig&Wepf Verlag    

年代:1987

数据来源: WILEY

摘要:

AbstractA mathematical procedure is developed to deal with the kinetics of ionic polymerization with impurity transfer and instantaneous initiation. Besides the technique of variable transformation, the integration of an implicit function is applied. The expressions of the molecular size distribution function and other molecular parameters are derived regorously, and several examples for numerical computations are given.

ISSN:0025-116X    

DOI:10.1002/macp.1987.021880210

出版商:Hüthig&Wepf Verlag    

年代:1987

数据来源: WILEY