... polymers of different chain length, 3. Ring-chain equilibrium, and 4. C/s-frans-equilibrium. The free enthalpy of polymerization (AGp) is sufficiently negative for rings of a size of 3, 4, 8, and ... larger to have the equilibrium on the side of the polymer. However, for rings of a size of 5, 6, and 7 - because of the low ring tension - the free enthalpy of polymer-ization can be even positive. ... of the c/s-polymer of cyclohexene, AGo,p = +6.2 kjmol"1 and for frans-polymer of cyclohexene, AGo,p = +7.3 kj mol"1 (14). Howev-er, at cryogenic temperatures, AGp decreases and...