CRACKING OF DICYCLOPENTADIENE

This invention provides a process for forming monomers from a dimer, wherein the dimer is dicyclopentadiene, di(methylcyclopentadiene), di(ethyleyclopentadiene), or a mixture of any two or more of these. The process comprises i) heating a liquid mixture comprising at least one dimer and at least one liquefying agent in a vaporization zone to at least the vaporization temperature of said mixture to form a vaporized mixture, wherein the vaporization zone consists essentially of a substantially straight conduit in which said liquid mixture occupies less than the entire cross sectional area of said conduit; and ii) introducing at least a portion of the vaporized mixture from i) into a cracking zone such that monomers are formed. This process is conducted at about atmospheric pressure.