摘要:

AbstractThe polymerization of acrylonitrile was studied in aqueous sulfuric acid with the redox initiator system, ceric ammonium sulfate/glycerol at 15–25°C. The initiation was effected by the ceric ion and the radical produced from the reaction of Ce4+with glycerol. At lower concentrations of Ce4+, the rate of monomer disappearance was proportional to [M]1,5, [G]0,5, and [Ce4+]0,5, and the rate of ceric ion disappearance was directly proportional to [Ce4+] and [G]. The results were explained by a kinetic scheme involving the oxidation of substrate by Ce4+to give the primary radical and further reaction of the latter with Ce4+to give the final product, and initiation of polymerization both by Ce4+and the primary radical. The initiation by Ce4+was found to be negligible as compared to that by the primary radical. The termination step is postulated to be mutual at lower concentrations of Ce4+and linear at higher concentrations of Ce4+. The induction period and the rate of polymerization was compared with those of other polyol systems, such as sorbitol and mannit

ISSN:0025-116X    

DOI:10.1002/macp.1977.021780301

出版商:Hüthig&Wepf Verlag    

年代:1977

数据来源: WILEY

摘要:

AbstractFour exchangers (8, 9, 16,and17) with cryptate forming anchor‐groups were prepared and their properties were studied. They were synthesized by the reaction of the cryptate formers6and7with chloromethylated polystyrene or by condensation of the cryptate formers14and15with formaldehyde or with formaldehyde/phenol. The exchangers were found to be very resistant towards heat and chemical attack. Their capacities for alkali salts amount to 1,0–1,3 mmol per gram of the air‐dried

ISSN:0025-116X    

DOI:10.1002/macp.1977.021780302

出版商:Hüthig&Wepf Verlag    

年代:1977

数据来源: WILEY

摘要:

AbstractThe synthesis of styrene polymers containing transition metals was achieved by reaction of different polystyrenes with Mt(CO)6or (CH3CN)3Mt(CO)3, (Mt = Cr, Mo, or W).Atactic, isotactic, and cross‐linked polystyrene (with divinylbenzene) were employed. Organometallic polymers with good stability were only obtained by coordination of tricarbonylchromium groups to the phenyl rings of the polystyrene. Tricarbonylmolybdenum‐ and tricarbonyltungsten complexed polystyrene showed very poor stability and could not be isolated. The amount of chromium incorporated depends on the molecular structure of the polymers, the chromiumcarbonyl complex used in the reaction, and the reaction time. The reactivity of the tris(acetonitrile)tricarbonylmetal‐complexes is higher than that of the hexacarbonylmetal‐complexes and the addition reactivity of the polymers is in the order:atactic>isotactic>cross‐link

ISSN:0025-116X    

DOI:10.1002/macp.1977.021780303

出版商:Hüthig&Wepf Verlag    

年代:1977

数据来源: WILEY

摘要:

AbstractCross‐linked copolymers from styrene and 1,2‐bis(4‐vinylphenyl)‐1,2‐ethanediol (1) were synthesized. The concentration of the pendent vinyl groups linked to the polymer was determined by means of IR‐spectroscopy as a function of the initial composition, of the total monomer concentration, and of the yield. The values were compared with previously elaborated theoretical calculations. Differences between experiment and theory are presumably due to an inhomogeneous distribution of the pendent vinyl groups in the polymerization system. Measurements of swelling with crosslinked copolymers from styrene and1showed, that the specific gel bed volume can be well correlated with the theoretically calculated concentration of cross‐links, if the total monomer concentration and the fraction of cross‐linking component are kept below certain maximum values and if the yield does not exceed 80

ISSN:0025-116X    

DOI:10.1002/macp.1977.021780304

出版商:Hüthig&Wepf Verlag    

年代:1977

数据来源: WILEY

摘要:

AbstractTreatment of sulfides withN‐chloro‐nylon‐6.6 in the presence of water or alcohols affords the corresponding sulfoxides in good yields.18O is incorporated in the corresponding sulfoxides by oxidation using H218O as oxygen source. A remarkable retardation of the oxidation is observed in the case of using alcohols with a bulky group. In the presence of optically active alcohols, the oxidation of sulfides results in the formation of optically active sulfoxides. The stereochemical route for the asymmetric oxidation is disc

ISSN:0025-116X    

DOI:10.1002/macp.1977.021780305

出版商:Hüthig&Wepf Verlag    

年代:1977

数据来源: WILEY

摘要:

AbstractThe title compound2was synthesized and its micellization in water investigated by proton magnetic resonance at 260 MHz. Chemical shift changes with concentration were observed, the largest change being for the aromatic protons indicating ordered phenylene rings in the micelles. The critical micelle concentration of this compound in D2O at 37°C was found to be approximately 0,010g/cm3

ISSN:0025-116X    

DOI:10.1002/macp.1977.021780306

出版商:Hüthig&Wepf Verlag    

年代:1977

数据来源: WILEY

摘要:

AbstractSynthesis and characterization of (S)‐3‐sec‐butyl‐9‐vinylcarbazole (7), (S)‐9‐(2‐methylbutyl)‐2‐vinylcarbazole (14), and (S)‐9‐(2‐methylbutyl)‐3‐vinylcarbazole

ISSN:0025-116X    

DOI:10.1002/macp.1977.021780307

出版商:Hüthig&Wepf Verlag    

年代:1977

数据来源: WILEY

摘要:

Abstract4,5,4′,5′‐Tetracyano‐2,2′‐bi‐1,3‐dithiolylidene (tetracyanotetrathiafulvalene) (1) was found to react with metal acetylacetonates (2a–m) to give dark, insoluble, and infusible polymers3a–mwith phthalocyaninelike structure. The electrical conductivity of the polymers was investigated (σ298K<6·10−5Ω−1cm−1), and a linear relationship between the logarithm of the electrical conductivity and the activation energy of the different polymers was found (compensation effect). Measurements of the thermoelectr

ISSN:0025-116X    

DOI:10.1002/macp.1977.021780308

出版商:Hüthig&Wepf Verlag    

年代:1977

数据来源: WILEY

摘要:

AbstractIt was found that a copper complex of toluene‐3,4‐dithiol (Cu‐TDT) catalyzes the oxidative polymerization of 2,6‐dimethylphenol (1), and the catalytic behavior was studied. The activity of the Cu‐TDT is higher than that of the known copper(II)‐pyridine complex. The higher the pyridine content in the solvent mixture pyridine/o‐dichlorobenzene, the higher is the activity of Cu‐TDT. Cu‐TDT loses its activity gradually in pyridine solution, however, about 40% of its activity remains even after 150h. The reasons for the high activ

ISSN:0025-116X    

DOI:10.1002/macp.1977.021780309

出版商:Hüthig&Wepf Verlag    

年代:1977

数据来源: WILEY

摘要:

AbstractIt was found that the manganese complex formed from toluene‐3,4‐dithiol and MnCl2(Mn‐TDT) and the complex formed from disodium 1,2‐dicyanoethylenedithiolate (maleonitriledithiol) (Mn‐MNT) show high activities as catalysts for the oxidative polymerization of 2,6‐dimethylphenol. Mn‐TDT is active only in the presence of an alkaline agent such as potassium hydroxide. Its activity is still higher when it is synthesized in ethanol and isolated just before use. Mn‐MNT is similarly active without being isolated, and it is active even in the absence of potassium hydroxide when the mole ratio MNT/Mn is high. This is probably due to the alkaline character of MNT. Mn‐TDT or Mn‐MNT complex produce poly[oxy(2,6‐dimethyl‐1,4‐phenylene)] selectively, and no formation of the diphenoquinone 2,2′,6,6′‐tetramethyl‐1,1′‐dioxo‐4,4′

ISSN:0025-116X    

DOI:10.1002/macp.1977.021780310

出版商:Hüthig&Wepf Verlag    

年代:1977

数据来源: WILEY