PROCESS FOR PRODUCTION OF POLYLACTONE POLYOLS, POLYLACTONE POLYOL COMPOSITIONS, AND COMPOSITIONS FOR POLYURETHANE RESINS

摘要

Polylactone polyols are produced by ring-opening polymerization of a lactone monomer with an initiator having an active hydrogen atom (such as polyol, polyamine, or the like) in the presence of an organotin catalyst in an extremely small amount (of about 0.01 to 10 ppm based on the total amount of the initiator and the lactone monomer). The production is conducted by a process comprising the first step of conducting the ring-opening polymerization at 180 to 210˚C until the ratio of unreacted lactone monomer to charged lactone monomer reaches 2 to 10 % and the second step of conducting the ring-opening polymerization at 100 to 175˚C until the ratio of unreacted lactone monomer to charged lactone monomer reaches to 0.5 wt% or below. This process makes it possible to lower the content of unreacted lactone monomer in the obtained polylactone polyol and the content of cyclic lactone dimer therein to 0.5 wt% or below and to 0.05 wt% or below, respectively.