Thermal silicon probes have demonstrated their potential to analyze the thermal properties of varied supplies at excessive decision. Nevertheless, a radical evaluation of the achievable decision is lacking. Right here, we current a probe-based thermal-imaging method able to offering sub-10 nm lateral decision at a sub-10 ms pixel price. We exhibit the decision by resolving microphase-separated PS-b-PMMA block copolymers that self-assemble in 11 to 19 nm half-period lamellar constructions. We resolve an asymmetry within the warmth flux sign at submolecular dimensions and assess the ratio of warmth flux into each polymers in varied geometries. These observations are quantitatively in contrast with coarse-grained molecular simulations of power transport that reveal an enhancement of transport alongside the macromolecular spine and a Kapitza resistance on the inner interfaces of the self-assembled construction. This comparability discloses a tip–pattern contact radius of a ≈ four nm and identifies combos of enhanced intramolecular transport and Kapitza resistance.