The desired degradation response is important, but the absence of nonspecific degradation is equally crucial. Thus, control polymer Bn-P2 was exposed to TBAF in the presence of DBU and NMA in DMF. No degradation was detected after 48 h (Figure ), corroborating the specific depolymerization imparted by the reactivity of the end-cap. In addition, TA-P2 and NB-P2 showed similar degradation profiles as TBS-P2 when actuated by β-mercaptoethanol (βME) and reduction (Zn/HOAc), respectively (Figures S105-S107). TBS-P3 underwent rapid degradation under the conditions used to depolymerize TBS-P2 (Figure ). However, a very significant background degradation was also observed for the corresponding non-responsive control Vi-P3 (Figure ). These degradation results clearly highlight the importance of strong steric hindrance in stabilizing the syringaldehyde-derived SIPs (P2) against undesired background degradation, without compromising their desired stimuli-responsive depolymerization.