RING-OPENING POLYMERIZATION OF 2-PHENYL-4,7-DIOXASPIRO[2.4]HEPTANE

1-Phenyl-4,7-dioxaspiro[2.4]heptane (1) was spontaneously copolymerized in bulk at 70-degrees-C with maleic and itaconic anhydride to give 1:1 alternating copolymer. Both the cyclopropyl and dioxapentyl rings were observed to open during the propagation. Copolymer yields, compositions and molecular weights are similar regardless of the presence of free radical initiator or inhibitor. A propagation mechanism via zwitterionic addition is suggested. Only homopolymers of styrene and acrylonitrile were isolated when these monomers were heated with 1 in bulk at 70-degrees-C in the presence or absence of AIBN. The cationic ring-opening oligomerization of 1 is also discussed.