POLYMETHYLALUMINIUM OXIDE AND STEREOREGULAR POLYMERIZATION OF PROPYLENE-OXIDE

1993-05-01
OKTEM, Z
SARI, A
ALYURUK, K
Polymethylaluminium oxide (PMAO) was prepared by reacting trimethylaluminium (AlMe3) with water in dilute dioxane solution. Several PMAO samples with different degrees of polymerizations (DP) were prepared (1 less-than-or-equal-to DP less-than-or-equal-to 7) either by changing reaction conditions or by fractionating the products. PMAO with DP about unity was found to be trimeric in dilute dioxane solutions but, in higher dielectric solvents, it partially dissociated into free ions. Electrical conductance measurements showed that the initially present ion-pairs were converted into another type of ion-pairs (solvent-bound ion-pairs) with a lower dissociation constant as the solution was aged. Catalytic activities of several PMAO samples in the stereoregular polymerization of propylene oxide were studied. Only a slight improvement of the stereoregular yield was observed by increasing the DP of the used catalyst. It was concluded that the methylaluminium oxide repeating units are the active species in the stereoregular polymerization and catalytic activity cannot be ascribed either to the presence of an ''undetected impurity'' or an ''unidentified unique structure of PMAO''.
EUROPEAN POLYMER JOURNAL

Suggestions

ELECTRO-INITIATED POLYMERIZATION OF BIS-(2,4,6-TRIBROMOPHENOXO) ETHYLENEDIAMINE COPPER(II) COMPLEX IN DMF AND ITS KINETIC-STUDY BY CYCLIC VOLTAMMETRY
Toppare, Levent Kamil; YIGIT, S; KISAKUREK, D; Akbulut, Ural (Elsevier BV, 1990-01-01)
The decomposition of bis-(2,4,6-tribromophenoxo) ethylenediamine copper(II) complex in dimethylformamide by electro-oxidation yields low molecular weight (4.5 × 103) linear poly(dibromophenylene oxide). Electro-initiated polymerization was accomplished upon oxidation by a constant potential electrolysis under air or under N2 at room temperature. Polymerization conditions were based on the peak potentials measured by cyclic voltammetry. Constant peak potentials carried out at anodic and cathodic peak potenti...
Electrochemical polymerisation of 2-aminofluorene in ethylalcohol/water medium
Imamoglu, T; Önal, Ahmet Muhtar (Elsevier BV, 2004-08-01)
Electrochemical polymerisation of 2-aminofluorene, 2AF, was investigated in ethylalcohol/water mixture (3:2, v:v) in the presence of HClO4 as the supporting electrolyte via constant potential electrolysis, CPE. Prior to CPE, electrochemical behaviour of the monomer was investigated in the same solvent electrolyte couple utilising cyclic voltammetry, CV. Electrochemical polymerisation of the monomer yielded insoluble, dark bluish-green, conducting polymer deposit on the electrode surface. Characterisation of...
POLYMERIZATION OF BIS(4-BROMO-2,6-DICHLOROPHENOXO) ETHYLENEDIAMINE COPPER(II) COMPLEX BY ELECTRO-INITIATION
KISAKUREK, D; YIGIT, S (Elsevier BV, 1991-01-01)
Bis(4-bromo-2,6-dichlorophenoxo) ethylenediamine copper(II) complex has been polymerized using electro-initiation by constant potential electrolysis, in dimethylformamide-tetrabutylammonium fluoroborate solvent-supporting electrolyte couple, at room temperature under air or N2. The process leads to low molecular weight (5.6 x 10(3)) linear poly(dichlorophenylene oxide). The structures of the polymers were determined by H-1-NMR and C-13-NMR. The kinetics of the polymerization were followed by in situ cycl...
A soluble and multichromic conducting polythiophene derivative
Varis, Serhat; Ak, Metin; Tanyeli, Cihangir; Akhmedov, Idris Mecidoglu; Toppare, Levent Kamil (Elsevier BV, 2006-10-01)
A new soluble polythiophene derivative was synthesized by both chemical and electrochemical oxidative polymerization of 1-4-nitrophenyl-2,5-di(2-thienyl)-1H-pyrrole (SNSNO2). Chemical method produces a polymer which is completely soluble in organic solvents. The structures of both the monomer and the soluble polymer were elucidated by H-1 and C-13-NMR and FTIR. The average molecular weight has been determined by GPC to be Mn = 6.3 x 10(3) for the chemically synthesized polymer. P(SNSNO2) was also synthesize...
Polymerization of propylene oxide and copolymerization of carbon disulphide and propylene oxide with xanthate salts
Aksoy, S.; Balkan, M.; Alyürük, K. (Elsevier BV, 1989-1)
Anionic polymerization of propylene oxide (PO) using several xanthate salts was studied. Low molecular weight oily polymers with variable sulphur content were obtained by using either potassium ethyl xanthate or potassium benzyl xanthate. The highest attainable conversion of PO was limited to ca 10%. The polymerization was accompanied by formation and precipitation of a by-product salt. In the presence of CS2, an oily copolymer with about 40% sulphur was obtained from the above mixtures. In reaction systems...
Citation Formats
Z. OKTEM, A. SARI, and K. ALYURUK, “POLYMETHYLALUMINIUM OXIDE AND STEREOREGULAR POLYMERIZATION OF PROPYLENE-OXIDE,” EUROPEAN POLYMER JOURNAL, pp. 637–643, 1993, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/66798.