Reactive degradable linear poly(aminoamide)s: synthesis, post-polymerization modifications and layer-by-layer coating†

The design of reactive biodegradable polymers and materials is an extremely important topic of research. This work presents the synthesis of a highly reactive and degradable poly(aminoamide) containing indole functional group in each repeating unit. The presence of indole functional groups allows for easy post-modification of such poly(aminoamide), enabling the synthesis of a library of functional poly(aminoamide)s via triazolinedione (TAD)–indole click reactions. Furthermore, the use of bifunctional TAD molecules facilitates the crosslinking of such poly(aminoamide), where the degree of crosslinking directly influencing the surface area of the resulting materials. The thermoreversible characteristics of such crosslinked material was also investigated. Additionally, such indole decorated poly(aminoamide) was used as an excellent platform for layer-by-layer coatings and surface functionalization. Degradation studies reveals that both the linear and crosslinked poly(aminoamide)s can be degraded in alkaline solution, where the crosslinked materials degrade faster compared to the linear analogues.