Structural mechanics of semicrystalline polymers prior to the yield point: a review

Abstract

The review focuses on the current studies of the deformation response and accompanying structural transformations of thermoplastic semicrystalline polymers subjected to uniaxial tension prior to the yield point. The mechanisms of strain-induced cavitation of amorphous layers and damages of crystalline lamellae are analyzed in line with novel results on the deformation behavior of solid polymers at temperatures exceeding the glass transition point. The coupling of viscoelastic and plastic deformation mechanisms with the small-strain structural transformations is critically discussed on the basis of the advanced theoretical modeling of mechanical properties of semicrystalline polymers.

The structural evolution of high-density polyethylene during crazing in liquid medium

“…High-density polyethylene (HDPE) is a profoundly investigated semicrystalline polymer, and numerous works [1][2][3][4][5][6][7][8][9][10] have been focused on studying the mechanism of its deformation and the evolution of its structure upon stretching in air. At the same time, items made of HDPE are frequently exploited in contact with various liquid and gaseous media.…”

Wide‐angle X‐ray scattering study of the lamellar/fibrillar transition for a semi‐crystalline polymer deformed in tension in relation with the evolution of volume strain

“…At the specimen scale, the orientation of the lamellae stacks is uniformly distributed. At a much smaller scale, the lamellae have been found not to be perfect crystals but instead have a granular substructure corresponding to an agglomeration of individual crystal blocks . This blocky substructure is essential if we are to understand the plastic deformation mechanisms of the lamellae.…”

Cyclic viscoplasticity of semicrystalline polymers with finite deformations

“…For a detailed discussion of these phenomena, the reader is referred to recent reviews (Seguela, 2007;Bartczak and Galeski, 2010;Patlazhan and Remond, 2012) and the references therein. Plastic deformations in the crystalline phase reflect (i) inter-lamellar separation, (ii) rigid rotation and twist of lamellae in stacks, (iii) fine slip of lamellar blocks (homogenous shear of layer-like crystalline structures), (iv) coarse slip of lamellar blocks (heterogeneous interlamellar sliding), (v) transformation of folded-chain lamellae into oriented mesomorphic phase, (vi) martensitic transformation of orthorhombic into monoclinic crystal phases, (vii) crazing and cavitation in large spherulites, (viii) fragmentation of lamellae into blocks linked by tie chains and formation of a mosaic structure, and (ix) alignment of lamellar blocks along the direction of maximal stress and formation of a fibrillar texture.…”