Higher 1,2-Epoxides

Propylene Oxide Polymers and Higher 1,2-Epoxide Polymers" under "Polyethers" in ECT3rd ed., Vol. 18, pp. 633—645, by R. A. Newton, Dow Chemical... 

Dreyfuss, P. and M. P. Dreyfuss, 1,3-Epoxides and Higher Epoxides, Chap. 2 in Ring-Opening Polymerization, K. C. Frisch and S. L. Reegan, eds., Marcel Dekker, New York, 1969. 

Farthing, A. C. Polymers from 1,3- and higher epoxides in high polymers. Vol. XIII, Chapter V. Polyethers Part I. Polyalkylene oxides and other polyethers. Ed. by N. G. Gaylord. New York Interscience Publishers 1963. 

Grignard reagent attach itself to the relatively positive carbon and the electrophilic (acidic) magnesium attach itself to the relatively negative oxygen. Use of higher epoxides is complicated by rearrangements and formation of mixtures. 

Other high-performance epoxy resins have been synthesized with the goal of achieving higher-temperature performance. Initially epoxy novolacs, which have a more rigid aromatic backbone and a higher epoxide functionality, were prepared. 

Anionic, base catalyzed polymerization of propylene oxide and higher epoxides are complicated by the E2 elimination acting as a chain transfer, e.g. 

Chain transfer reactions to monomer occur with other homologs of propylene oxide. The reactivity of higher epoxides decreases as expected based on steric hindrance effects on nucleophilic attack at the oxirane carbons. 

With the increased demand for high temperature and high humidity resistance, new resins have been developed which have higher epoxide and aromatic content. Three resins which fit the category are TACTIX 742 (Dow), Ar-aldite MY 720 (Ciba-Geigy), and Epon 1031 (Shell). Their idealized structures are ... 

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