Four urethane acrylate oligomers were synthesized by a reaction of an excess of isophorone diisocyanate polypropylene glycol Acclaim 4200N (P) with a subsequent reaction of nonreacted D with a hydroxy acrylate Tone M100 (A). The latter has a common name caprolactone acrylate. Oligomers were prepared by different ways of addition of 13 to D or D to P and at different ratio of [D]/[P]. The fifth oligomer AIDA was prepared as in individual compound. Viscosities, GPC traces, T-g's of oligomers were taken alongside with other physical properties of cured oligomers. It was demonstrated that oligomers with P con-sist of ADPDA, ADA, and of a chain-extended product A... P-n... A, which has two or more Ps in a molecule. Additive contributions of these three components essentially determine properties of the liquid and cured oligomers. structure-property relations Of urethane acrylate oligomers are discussed. (c) 2005 Wiley Periodicals, Inc.