Assessing the Possibility of Isomerization Preceding Polymerization

Since 0-pinene readily isomerizes to a-pinene and other pn uets in acidic media (20), it was important to examine the possibility of isomerization under our polymerization conditions. Thus a polymerization experiment has been carried out under conditions conducive for isomerization ([M] = 3.5 Af, [EtAKla ] = 10 M, —70°, for 30 minutes). Conversion was about 6%. After quenching with methanol and workup as described in Section B, the liquid charge was extracted with water (to remove methanol) and subsequently with n-pentane. The ccmiposition of the extract was analyzed by G.C. and compared with an original 0-pinene sample. According to gas chromatographic analysis, -pinene did not isomerize and the composition of the liquid charge was virtually identical before and after polymerization e.g., 98% pi-nene, 0.9% a-pinene and 1.1% unidentified compounds. 

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