Ultrafast catalytic charring towards anti-flammable thermoplastic polyurethane with superior dripping suppression and fire protection

•Unbalance of degradation and crosslinking was key to fire safety and dripping of TPU.•Unique ultrafast catalytic charring was validated via lamella-on-sphere intumescence.•UL-94V-0 with a suppressed dripping was screened at a low 5wt% loading.•An exceptional fire protection was witnessed by mechanical response of fire chars.•Condensed-phase radical scavenging and atomic-level catalysis accounted for excellence.