Synthesis of elastomers by cationic polymerization with expansion in volume

Abstract

Abstract A bifunctional bis spiro ortho ester, hydroquinone bis‐(1,4,6‐trioxaspiro[4.4]non‐2‐ylmethyl) ether, was prepared in a 30% yield by treating hydroquinone diglycidyl ether with γ‐butyrolactone in the presence of boron trifluoride etherate. Copolymerization of a mixture consisting of 90% of 1,4,6‐trioxaspiro[4.4]‐nonane and 10% of the bis spiro ortho ester produced an elastomer with essentially no change in volume. Condensation of ethylene thiocarbonate with pentaerythritol in the presence of tributyltin oxide gave a 20% yield of a bis spiro ortho carbonate, 1,4,6,10,12,15,16,19‐octaoxatrispiro[4.2.2.4.2.2]nonadecane. Copolymerization of a mixture consisting of 90% of 1,5,7,11‐tetraoxaspiro[5.5]undecane and 10% of the bis spiro ortho carbonate gave an elastomer with a 3% increase in volume.