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This book covers three different research topics in the field of science and technology of polymeric materials. They all have in common the fact that the knowledge of the yield and/or the post yield behavior is necessary for their analysis. Further, they all deal with semicrystalline polyolefins. The first one regards the study of the yield and post-yield behavior of syndiotactic polypropylene in relation to the strain-induced structural changes. The second one regards a methodology to characterize fracture toughness of polymeric films, the Essential Work of Fracture. The validity of this method requires that the fracture propagation occurs within plastically deformed material. The last topic concerns a method to predict the long term failure of polymeric materials under creep loading when the plasticity controlled failure occurs. This book is divided in four chapters. In the first one a brief description of the main deformation mechanisms of semicrystalline polymers,is presented. The next three chapters deal with the topics presented. This book is aimed at students specializing in polymers mechanical behaviour but also at researchers and teachers in polymer mechanics

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Nadia Perillo was born in Caserta (IT) in 1986. She has studied Materials Engineering at Università degli Studi di Napoli Federico II and she has got 1°and 2°level degree cum laude. She has attended the PhD course in Materials Engineering at POLIMI developing a thesis on yield behaviour of semicrystalline polymers. Now she works at BM Plastic (BG)

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