Synthesis and polymerization of bicyclo[2,2,$1^{8,11}$] hept-7,9-yl-2-methylene-1,4,6-trioxaspiro-[4,4]nonane

Abstract

Bicyclo[2,2,$1^{8,11}$] hept-7,9-yl-2-methylene-1,4,6-trioxaspiro [4,4]nonane(BIMTN) was synthesized by the reaction of 6-oxatricyclo[3,2,1,$1^{3,8}$]nonan-7-one with epichlorohydrin followed by dehydrochlorination. BIMTN was polymerized with cationic initiators such as boron trifluoride etherate and aluminum chloride to produce a low molecular weight polymer. BIMTN was also polymerized using di-tert-butyl peroxide(DTBP) as an initiator to give a soluble polymer which has a good thermal stability. The IR and NMR spectra indicated that the structure of the polymer obtained by DTBP contains ester and ketone group due to the radical double ring opening processes in the polymer backbone. In the radical ring-opening polymerization, high dilution was observed to promote the radical ring-opening process. Thus, BIMTN, when treated with di-tert-butyl peroxide at 120℃ in xylene, gave a polymer in which about 50% of the ring-opened linkage, however, it does not undergo polymerization with benzoyl peroxide(BPO). The copolymerization studies of BIMTN with comonomers like MMA(methyl methacrylate) and AN (acrylonitrile) were conducted. The copolymerization of BIMTN with MA(maleic anhydride) gave spontaneously rise to the alternating copolymers by the participation of charge transfer complexes. However, low conversion was observed.