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The interaction of light with polymers can be positive, where light enhances polymerization or performance, but it can also be negative towards the targeted properties. Positive and negative interactions between polymers and light are highlighted. 

Abstract Photodegradable nanoparticles with sphere, worm, and vesicle morphologies were synthesized following polymerization induced self‐assembly (PISA), incorporating a photoresponsive phenyl vinyl ketone (PVK) block and a nonphoto responsive 2‐hydroxypropyl methacrylamide (HPMA) block. The photodegradation of nanoparticles under UV revealed that the initial shapes of sphere and vesicle particles are retained even until 7 h and after 24 h of photo‐induced degradation, respectively, despite a significant reduction in molecular weight (M_n). This could be due to the assembly of degraded PVK fragments in the hydrophobic region, maintaining the relative hydrophilic to hydrophobic ratio. However, worm nanoparticles exhibited a fast morphology reversal after 2 min of degradation, yielding sphere nanoparticles. Therefore, photo responsive PVK nanoparticles with morphology and conversion‐dependent degradation behavior were explored. Furthermore, undegraded and degraded nanoparticle coatings exhibited different surface properties, determined by contact angle measurements, with both morphology and degradation impacting the surface properties. Finally, the PVK nanoparticles could encapsulate molecules and release them upon degradation. Therefore, this study can ultimately be applied to numerous fields due to the potential uses of degradable polymers in various material systems, especially for the controlled release of agrochemicals, cleaning agents, or antifungal agents, as well as to enable surface modifications upon degradation. 

Polyvinyl esters are used in many applications, however, high molecular weight polyvinyl esters have many challenges, with strategies for the synthesis of these polymers being the focus of this work. 

The RAFT rate retardation effect is used to classify monomers according to their reactivity. The stability of the radical correlates inversely with the extent of retardation allowing a framework for classifying monomer reactivity to be established. 

Polymer networks based on phenyl vinyl ketone were synthesized. The introduction of a second network enhanced the control over the material's photodegradation, as well as modulating the mechanical properties. 

Characterization of polymer networks presents unique challenges due to the insolubility of the materials, but this also enables characterization by new techniques that take advantage of the bulk network structure.