The exposure characteristics of norbornene-based photosensitive sacrificial materials as functions of the photoinitiator have been investigated. The results show that the initiator, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, provides high photosensitivity and an adjustable contrast factor. The kinetics of the thermal decomposition of the polymers have been investigated with dynamic and isothermal thermogravimetric analysis to determine the most appropriate conditions for the thermal decomposition of the sacrificial polymers. The reaction is slightly higher than first-order, and a single mechanism can account for the decomposition throughout the process. The dependence of the kinetic parameters on the composition of the copolymers has been studied, and the reaction order remains unchanged; however, the activation energy is lower when the alkenyl-substituted norbornene content is increased in the copolymers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1186–1195, 2003