Cover Image, Volume 137, Issue 12

Elastomer always exhibited poor efficiency for toughening flame‐retardant polymer. In intumescent flame‐retardant HDPE, a novel multi‐steps processing method was employed by Chang Lu and colleagues, to fabricate a partial wetting structure in which LLDPE‐g‐MAH phase with the sphere was dispersed at the interface. The partial wetting structure caused a remarkable improvement of the toughness of flame‐retardant HDPE with 2 wt% LLDPE‐g‐MAH. Its elongation at break and notched impact strength were 43% and 270% higher, respectively, than that of neat HDPE. The unique interface failure mode should be responsible for the high impact strength. DOI: 10.1002/app.48735