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We report a photo-triggered, base generating, base propagating degradable polyurethane that is triggered by 365 nm UV light irradiation. A small area of this polyurethane material can be exposed to 365 nm UV light irradiation to generate basic species that can initiate a base propagated degradation process within the bulk material leading to global degradation without the need for continous UV irradiation. The polymer was synthesized by a polycondensation polymerization of a small amount of o -nitrobenzene diol 2 , a large amount of Fmoc-based diol 3 , and hexylmethylene diisocyanate. Integrating both photosensitive and base-sensitive carbamate moieties into the polymer 1 backbone provides the UV light-triggered base propagating degradable polyurethane material. Degradation studies of polymer 1 using 1 H NMR and gel permeation chromatography (GPC) suggest that initial UV irradiation triggers the degradation of the photosensitive o -nitrobenzene carbamate linkages, releasing a primary amino group that causes a cascade of amines to form by further degrading the remaining Fmoc carbamate groups. A bulk polyurethane film was prepared using Fmoc-based triol 4 as a monomer. UV-irradiation of a small localized area of the film initiates the propagation throughout, leading to efficient bulk degradation of the entire material. The amine degradation products could be utilized to make a one-pot epoxy adhesive, showing a potential upcycling application of this self-propagating degradable polyurethane system.