Superacids and Their Derivatives. IX. Selective Cyclodimerization of Etylene Oxide to 1,4-Dioxane Catalyzed by Superacids and Their Derivatives

Kobayashi, Shiro; Morikawa, Kenji; Sàegusa, Takeo

doi:10.1021/ma60048a052

Cited by 32 publications

(25 citation statements)

References 6 publications

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“…In the polar solvent CHsNOz the isomerization of monomer to methyl ethyl ketone was noticed and a lesser amount of dioxanes was formed. Three distinct features were seen in the polymerization of (1) in Table I 1 (1) Oxonium initiators gave higher cyclic polyethers and only slight amounts of cyclic dimers. (2) Superacid derivatives yielded methyl ethyl ketone, dioxolane, and dioxane cyclodimers and randomly distributed higher oligomers that included those with acetal linkage.…”

Section: Effects Of Solventsmentioning

confidence: 96%

Reaction scheme in the cationic polymerization of substituted epoxides

Kawakami

Ogawa

Yamashita

1979

J. Polym. Sci. Polym. Chem. Ed.

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Section: Effects Of Solventsmentioning

confidence: 96%

Reaction scheme in the cationic polymerization of substituted epoxides

Kawakami

Ogawa

Yamashita

1979

J. Polym. Sci. Polym. Chem. Ed.

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“…It was not suprising that triflic acid derivatives gave polymers of low molecular weight, in view of our earlier experience in the preparation of poly(ethylene oxide) from ethylene oxide. 19 The other possible source of! ow molecular weight of our Poly-EG and copolymers is the cationic chain transfer possibility of the ester group, as described below.…”

Section: Resultsmentioning

confidence: 99%

“…1 H NMR spectra were taken on a Varian HA-100 or Hitachi R-20B (60 MHz) instrument. 19 F NMR spectra were taken on a Hitachi R-20B (54 MHz) instrument.…”

Section: Measurementsmentioning

confidence: 99%

“…The tube was then gradually warmed to room temperature and was kept at 35°C to allow the polymerization to proceed. When desirable, the reaction was followed by monitoring the 1 H or 19 F NMR spectrum at 35°C. After the reaction was considered complete, the polymerization was stopped by opening the NMR tube and 464 adding an approximately 10 % solution of aqueous ammonia in methanol (0.1 ml).…”

Section: Preparationsmentioning

confidence: 99%

“…Broad overlapping bands between 3.5 and 4 ppm indicate the methylene and methine protons. The initiation step was examined by 19 F NMR spectroscopy. A mixture of 5.0 mmol of EG and 5.2 mmol EtOTf in 5 ml of chloroform was kept at 35oc for 30 days.…”

Section: Homopolymerization Of Egmentioning

confidence: 99%

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Cationic Homo- and Co-polymerizations of Ethyl Glycidate

Sàegusa

Kobayashi

et al. 1979

Polym J

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ABSTRACT:Cationic homo-and co-polymerizations of ethyl glycidate (EG) have been studied with triethyloxonium tetrafluoroborate (TEOFB) and superacid ester catalysts. The homopolymerization of EG gave a paste-like material of low molecular weight with TEOFB catalyst. A superacid ester catalyst such as ethyl trifluoromethanesulfonate underwent only the initiation process with EG and the propagation was negligibly slow in this system. Copolymerization of EG with tetrahydrofuran (THF) gave a copolymer with TEOFB. When THF remained unreacted after the completion of copolymerization, the copolymer composition was in all cases EG: THF = I : 2. These results were understood in terms of the penultimate effect. The same copolymerization by a superacid ester catalyst, however, always yielded copolymers of the EGITHF= 112 composition. This result was explained in the same way as the TEOFB case, taking the EG polymerizability by a superacid ester into account.KEY WORDS Ethyl Glycidate Cationic PolymerizationCopolymerization I Tetrahydrofuran I Oxonium Salt I Superacid Ester I Penultimate Effect I Cyclic ethers and particularly epoxides have been known for a long time to polymerize to polyethers even of very high molecular weight. 1 • 2 While cyclic ethers polymerize primarily with classical cationic initiators and aluminum and zinc organic compounds by what is often referred to as coordinative anionic polymerization, 3 epoxides undergo polymerization by classical cationic and anionic mechanisms and also by the above mentioned coordinative mechanism. 1 • 2 Most of the work has been done on unsubstituted and methyl-substituted compounds, namely ethylene oxide and propylene oxide; substitutent groups with higher polarity and the functionality have not been studied to any extent. The monomers with the most reactive groups were those with a chloromethyl substitution as, for example, in epichlorohydrin 4 and 3,3-bis(chloromethyl)oxetane. 5 agent, which in turn must be prepared from 90 % H 2 0 2 and trifluoroacetic acid. Glycidaldehyde, 7 glycidyl esters, 8 and glycidonitrile 7 have been prepared; glycidaldehyde was polymerized via both the epoxide group and the aldehyde group, depending on the reaction conditions. 9 These monomers have been copolymerized with trioxane 10 and the properties of co-and ter-polymers with 1,3-dioxolane with a relatively low percentage of glycidate incorporated were investigated. 11 These polymers were then hydrolyzed to the corresponding poly( oxymethylene)ionomers and their free acids. The co-and terpolymerizations were accomplished with classical cationic initiators, both in bulk solution 11 and by a process in which the monomers were mixed in the vapor phase. 12 Epoxides which have functional groups directly attached to the epoxide rings have been already known. 6 Their synthesis is not particularly easy as it requires trifluoroperacetic acid as the oxidizing It was the. purpose of this work to study the cationic homo-' and co-polymerization of ethyl glycidate, especially the investigation of suitab...

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Physical Data of Oligomers

Rothe

1999

The Wiley Database of Polymer Properties

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Superacids and Their Derivatives. IX. Selective Cyclodimerization of Etylene Oxide to 1,4-Dioxane Catalyzed by Superacids and Their Derivatives

Cited by 32 publications

References 6 publications

Reaction scheme in the cationic polymerization of substituted epoxides

Reaction scheme in the cationic polymerization of substituted epoxides

Cationic Homo- and Co-polymerizations of Ethyl Glycidate

Physical Data of Oligomers

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