Hydroxyl-terminated polybutadiene, HTPB, carbon-13 spin-lattice(T-1) and nuclear Over-hauser effect (NOE) relaxations data, obtained as a function of temperature (-50 to +70 degreesC), in CDCl3, suggest that a log chi(2) distribution model is the most appropriate, in describing HTPB chain segmental motions. The local segmental motions are the major sources of relaxations, for the HTPB protonated carbons. The relaxation data show the chain segmental motions taking place in very short time intervals (on the order of tenth of a nanosecond). The activation energies of such conversions, from one conformer to another, are found to be on the order of kilojoules.