The emerging field of CDr polymers (polymers that are capable of continuous depolymerization mediated by a reaction based detection unit) represent a unique opportunity to develop materials that provide an highly selective amplified response to a specific stimulus. The design of CDr polymers feature a polymer capped with a stabilizing functionality chosen specifically to respond to a chemical or physical signal. When the signal of interest cleaves the bond between the polymer and this cap, the resulting polymer continuously and completely depolymerizes from head-to-tail. Poly(phthalaldehyde) (PPA) and its derivatives are a class of CDr polymers that depolymerize to monomer completely in seconds to minutes in environments that vary substantially in polarity. This dissertation describes efforts (i) to develop new methodology for synthesizing PPA, which enabled research into using PPA as stimuli-responsive microscale pumps and core-shell microcapsules, and (ii) to synthesize a novel poly(phthalaldehyde) derivative (poly(4,5-dichlorophthalaldehyde, PCl2PA) with improved stability, which led to use of PCl2PA as multi-responsive materials prepared using selective laser sintering.