“…As the strain increases further, these undulations grow and transform into bigger folds or angular kinks that may eventually form a chevron morphology [ 16 ]. Such morphology, originating from microbuckling instability, was also observed at the nano- and micrometer scale in block copolymers with a well-oriented lamellar morphology [ 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ] and in semicrystalline polymers, either unoriented [ 4 , 9 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ] or oriented [ 13 , 24 , 25 , 29 , 32 ].…”