Reproducible and scalable synthesis of end-cap-functionalized depolymerizable poly(phthalaldehydes)

This article describes a general procedure for synthesizing end-capped poly(phthalaldehydes) that depolymerize continuously from head-to-tail in response to a single reaction with a specific chemical or physical stimulus. The procedure (i) is reproducible and scalable over various batches of commercially available monomer, (ii) requires only 4 h to prepare the polymer, (iii) enables functionalized end-caps to be appended to both ends of the linear polymer, and (iv) provides control over the molecular weight of the polymer. This article also (i) provides spectroscopic and experimental evidence that depolymerization of end-capped poly(phthalaldehydes) is mediated by cleavage of the end-cap from the terminus of the polymer in response to a specific applied signal and (ii) shows that plastics made from poly(phthalaldehyde) containing a photoresponsive end-cap can be converted to monomers in the solid state.