In summary, bio-based polymers were synthesized via thiol-ene click polymerization of monomers derived from lignin-derived aldehydes. These polymers were used in polymer-polymer coupling to efficiently access block copolymers via thiol-Michael addition click reaction. Moreover, diverse thiol-containing stimuli-reactive end-caps were readily introduced into a single bio-based polymer precursor via thiol-ene click reaction, providing a general approach to access triggerable SIPs. The syringaldehyde-derived SIPs in particular underwent cascade depolymerization through alternating 1,6-elimination and cyclization reactions upon selective removal of their end-caps, while exhibiting high stability in the absence of stimuli. Overall, this work opens a new avenue for designing biobased polymers with stimuli-triggered degradability via highly efficient click reactions. The exploration of applications of these biobased SIPs are underway in our lab.