Multiple Shape‐Memory Behavior of Polyethylene/Polycyclooctene Blends Cross‐Linked by Electron Irradiation

Covalent networks prepared by electron irradiation of binary and ternary blends of linear and/or short‐chain branched polyethylenes as well as polycyclooctene (polyoctenamer) demonstrate distinctly developed triple‐ and partly quadruple shape‐memory (SM) behavior after one‐step programming. Blends having the morphology with well‐segregated phases, where the matrix has the lower melting/switching temperature in comparison to the disperse phases, evince pronounced steps of SM recovery and modulus as well as distinct differential scanning calorimetry‐melting peaks. Phase morphology and especially phase separation in networks are noticeably affected by thermal history of blends before cross‐linking. All investigated networks show high SM performances with strain fixing and strain recovery ratios of 95–99%. magnified image