Microfibrillar structures Undeformed spherulite Deforming spherule ∩∩ Fracture Neck forms Material fully drawn Elastic limit Strain E From Samuels, R.J. Structured Polymer Properties. New York: Wiley-Interscience, 1974From Samuels, R.J. Structured Polymer Properties. New York: Wiley-Interscience, 1974