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  • 1
    Electronic Resource
    Electronic Resource
    The potentiometric behaviour of copolymers of methacrylic acid in water-ethanol solutions (1986)
    Springer
    Polymer bulletin 16 (1986), S. 195-200 
    Details
    ISSN: 1436-2449
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary The synthesis is reported of copolymers of styrene with methacrylic acid and of methyl methacrylate with methacrylic acid by radical copolymerization, of copolymers of methyl methacrylate with methacrylic acid by partial alkaline hydrolysis of poly(methyl methacrylate), and of block copolymers of styrene with methacrylic acid. Modified titration curves of all these copolymers were recorded in water and water-ethanol solutions. In a solution containing 50 mass.% ethanol, only small differences could be observed between the potentiometric behaviour of the individual copolymers and polymethacrylic acid. Also, there were no essential differences in any of the solvents used between the potentiometric behaviour of block copolymers of styrene with methacrylic acid, on the one hand, and polymethacrylic acid, on the other. On the contrary, maxima and minima were always observed on the modified titration curves of statistical copolymers with a higher content of the hydrophobic comonomer in solutions with a high water content. Thus, using the modified titration curves, it is possible to decide whether a given copolymer is of the block or statistical type.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00955491
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  • 2
    Electronic Resource
    Electronic Resource
    Synthesis and properties of powdery hydrogels based on acrylamide, methacrylamide, and their N-substituted derivatives (1996)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 243 (1996), S. 151-159 
    Details
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Leicht vernetzte Hydrogele auf der Basis von Acrylamid, N-(1,1-Dimethyl-3-oxobutyl)acrylamid, N,N-Dimethylacrylamid, Methacrylamid, N-(2-Hydroxypropyl)-methacrylamid und N-[Tris(hydroxymethyl)methyl]methacrylamid wurden in Form von pulverigen Substanzen synthetisiert, die aus Aggregaten sehr kleiner Partikel (∼10-1 μm) bestehen. Die pulverartigen Hydrogele wurden durch Fällungspolymerisation in Aceton und Diethylether unter Verwendung von N,N′-Methylenbisacrylamid und Ethylendimethacrylat als Vernetzungsmittel synthetisiert. Es wurden die Abhängigkeiten des Quellungsgrades in Wasser, der Größe, des Aggregationsgrades und der spezifischen Oberfläche von Partikeln, und des Inhalts von wasserlöslichen Substanzen in den Hydrogelen von den Bedingungen ihrer Synthese verfolgt. Die Eignung einzelner der synthetisierten Hydrogele für die Herstellung von Silikon-kautschuk-Hydrogel-Kompositen wird diskutiert.
    Notes: Lightly crosslinked hydrogels based on acrylamide, N-(1,1-dimethyl-3-oxobutyl)-acrylamide, N,N-dimethylacrylamide, methacrylamide, N-(2-hydroxypropyl)methacrylamide and N-[tris(hydroxymethyl)methyl]methacrylamide were synthesized in form of fine powders, consisting of aggregates of very small (∼10-1 μm) particles. The powdery hydrogels were obtained by precipitation polymerization in acetone and diethyl ether, using N,N′-methylenebisacrylamide and ethylene dimethacrylate as crosslinking agents. Dependences of water-swellability, particle size, aggregation, specific surface and content of the uncrosslinked water-soluble polymers and low-molecular-weight substances in the hydrogels on the conditions of their synthesis were studied. Suitability of particular powdery hydrogels synthesized for the preparation of silicone rubber-hydrogel composites is discussed.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1996.052430113
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  • 3
    Electronic Resource
    Electronic Resource
    Precursors of hydrophilic polymers, 3Part 2: cf.1.. The potentiometric behaviour of isotactic and atactic poly(2-dimethylaminoethyl methacrylate) in water/ethanol solutionsTo Dr. M. Bohdanecký on the occasion of his 60th birthday (1985)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 186 (1985), S. 111-121 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The dissociation constants of partially ionized isotactic and atactic poly(2-dimethylaminoethyl methacrylate) in water/ethanol solutions were measured. The strong dependence of the apparent dissociation constant on the degree of ionization of the macromolecule is discussed using viscometric data and compared with the properties of low-molecular-weight model compounds. The values of the internal dissociation constants at various ionic strength in various water/ethanol solutions were obtained by extrapolation of the apparent dissociation constants to zero ionization degree of the macromolecule. The conformational structures of macromolecules in solution are discussed.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1985.021860111
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  • 4
    Electronic Resource
    Electronic Resource
    Precursors of hydrophilic polymers, 6Part 5: M. Přádný, S. Ševčik, Makromol. Chem. 186, 1657 (1985).. Preferential sorption of water on poly[2-(dimethylamino)ethyl methacrylate] in ethanol/water mixtures (1986)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 187 (1986), S. 2191-2198 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The study deals with the kinetic behaviour of atactic and isotactic poly[2-(dimethylamino)-ethyl methacrylate] (PDAEM) and of low-molecular-weight tertiary amines in the quaternization by low-molecular-weight alkyl iodides (Mentschutkin's reaction) in water/ethanol solution at 60°C. Unlike quaternization of PDAEM with methyl iodide and 2-iodoethanol, in the cases of the other alkyl iodides the rate constant of quaternization depends on the initial concentration of the alkyl iodide. The rate constant decreases with increasing concentration of the alkyl iodides. The effect becomes more pronounced in a reaction medium containing 43 wt.-% of water in a mixture with ethanol as compared to azeotropic ethanol. Such behaviour is attributed to the fact that in solution of a water/ethanolic mixture the tertiary amines investigated in this study are preferentially solvated by water.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1986.021870915
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  • 5
    Electronic Resource
    Electronic Resource
    Precursors of hydrophilic polymers, 7Part 6: cf.4.. Potentiometric properties and structure of copolymers of 2-dimethylaminoethyl methacrylate (1987)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 188 (1987), S. 227-238 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The 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 pK0 values of copolymers and pK values 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 quaternization reaction.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1987.021880201
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  • 6
    Electronic Resource
    Electronic Resource
    The use of low-molecular-weight model compounds in an investigation of polyelectrolytes, 2.Part 1: cf.1. Potentiometric properties of poly[(methacrylic acid)-co-(2-dimethylaminoethyl methacrylate)] and its quaternary ammonium salt (1990)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 191 (1990), S. 435-443 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The potentiometric behaviour of two polyampholytes, poly[(methacrylic acid)-co-(2-dimethyl-aminoethyl metharylate)] and poly{(methacrylic acid)-co-[2-(methacryloyloxy)ethyltrimethyl-ammonium iodide]} is described. The dissociation constants of low-molecular-weight compounds modelling the structural units and diads of polyampholytes are reported, and effects of adjacentgroups on the potentiometric behaviour of the copolymers are discussed.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1990.021910218
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  • 7
    Electronic Resource
    Electronic Resource
    Model compounds of poly(methyl methacrylate). Conformational structure of the dimethyl esters of 2,2,4-trimethyl- and of 2-methoxymethyl-2,4-dimethylglutaric acid. 13C NMR, 1H NMR and vibrational spectroscopic study (1985)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 186 (1985), S. 1905-1918 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The conformational structure of the dimethyl esters of 2,2,4-trimethylglutaric acid, and of the erythro- and threo-isomers of 2-methoxymethyl-2,2,4-dimethylglutaric acids was studied by NMR and vibrational spectroscopic methods. Conformational structure generated by rotation about skeletal bonds was determined by analysis of vicinal coupling in 1H and 13C NMR spectra. The results are discussed in relation to the conformational structure of PMMA.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1985.021860918
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  • 8
    Electronic Resource
    Electronic Resource
    Precursors of hydrophilic polymers, 8Part 7: cf.2. The structure of copolymers of 2-dimethylaminoethyl methacrylate and 2-methacryloyloxyethyltrimethylammonium iodide (1987)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 188 (1987), S. 2875-2883 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Quaternization reactions of poly(2-dimethylaminoethyl methacrylate) using methyl iodide were carried out up to 50% conversion in 18 chemically different solvents. Copolymers which contain moderate hydrophilic 2-dimethylaminoethoxycarbonyl groups and strongly hydrophilic 2-trimethylammoniumethoxycarbonyl iodide groups were obtained. Potentiometric titration showed that in some solvents the reaction proceeds by the zip mechanism, i.e. copolymers with a predominantly block structure are formed, while in other solvents the reaction proceeds along the macromolecular chain randomly, that is, giving rise to statistical copolymers.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1987.021881210
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  • 9
    Electronic Resource
    Electronic Resource
    Precursors of hydrophilic polymers, 5Part 4: cf.1. Activation parameters of quaternization of poly(2-dimethylaminoethyl methacrylate) with methyl iodide (1985)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 186 (1985), S. 1657-1663 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The paper deals with the quaternization reaction of isotactic and atactic poly(2-dimethylaminoethyl methacrylate) with methyl iodide in three water-ethanol solutions at different temperatures. Using the temperature dependence of the rate constants extrapolated to zero conversion, the activation quantities at the beginning of the reaction were calculated (activation energy, enthalpy, entropy, free enthalpy, and the frequency factor). The reactivities of the two polymers are compared with each other and then also with that of a low-molecular weight model compound, 2-dimethylaminoethyl pivalate (DAEP). Reactivity of all compounds under investigation increases with increasing water content in the solvent: that of DAEP due to the decreasing negative activation entropy, that of the two polymers as a result of decreasing activation energy. Using the measured activation energies and entropies, polarity of the transient state of the polymers is discussed in comparison with the low-molecular weight model, along with polymeric effects which may become operative in the quaternization reaction.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1985.021860813
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  • 10
    Electronic Resource
    Electronic Resource
    The use of low-molecular-weight model compounds in an investigation of polyelectrolytes, 1. Potentiometric properties of poly(methacrylic acid) and its 2-dimethylaminoethyl esterTo Prof. Otto Wichterle on the occasion of his 75th birthday (1989)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 190 (1989), S. 1079-1088 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The potentiometric behaviour of poly(methacrylic acid) (PMA), poly(2-dimethylaminoethyl methacrylate) (PDAEM), and low-molecular-weight compounds modelling the structural diad of these polymers, 2,2,4,4-tetramethylglutaric acid (TMGA) and its 2-dimethylaminoethyl ester (ETMG), is reported. The dissociation constants of these compounds to the 1st and 2nd degree were measured and compared with the values for polymers. It appears that TMGA adequately models the behaviour of PMA up to the conformational transition compact coil (stage “a”)  -  random coil (stage “b”) at higher ionic strength values of the titrated solution. On the contrary, ETMG behaves as a typical low-molecular-weight compound with properties differing from those of PDAEM.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1989.021900516
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