Semi-crystalline polymers plastic deformation

In Section 9.3 we present experimental studies of plastic deformation in two semi-crystalline polymers, HDPE and Nylon-6, both in tension and in plane-strain compression flow, from initial spherulitic morphologies to large plastic strains. In these studies, the evolving morphological alterations were monitored closely by a complementary array of techniques involving light microscopy and X-ray diffraction and scattering both in the crystalline and in the amorphous components. 

Haudin, J. M. (1982) Plastic deformation of semi-crystalline polymers, in Plastic Deformation of Amorphous and Semi-Crystalline Materials, edited by Escaig, B. and G Sell, C., Les Ulis Les Editions de Physique, pp. 291-311. 

Lee, B. J., Parks, D. M., and Ahzi, S. (1993b) Micromechanical modeling of large plastic deformation and texture evolution in semi-crystalline polymers, J. Mech. Phys. Solids, 42, 1651-1687. 

In all plastic deformation, plastic strain results from the accumulation of stress-driven and thermally assisted unit events that were discussed in Chapters 7-9 for amorphous metals, glassy polymers, and semi-crystalline polymers. In 3D, under a general applied stress tensor, plastic deformation can be initiated at 0 K when the deviatoric shear component of the applied stress, which we designate as plastic-shear resistance r that is, in general, dependent on a previous history of plastic deformation, which is characterized by a deviatoric plastic shear strain -f (Chapter 3). 

J.M. Haudin, Plastic deformation of semicrystalline polymers, in Plastic Deformation of Amorphous and Semi-crystalline Materials, ed. by B. Escaig, C. G Sell (Les Editions de Physique, Paris, 1982), p. 291... 

Seguela R (2002) Dislocation approach to the plastic deformation of semicrystalline polymers kinetic aspects for polyethylene and polypropylene. J Polym Sci B Polym Phys 40 593 Seguela R (2005) On the strain-induced crystalline phase changes in semi-crystalline polymers mechanisms and incidence on the mechanical properties. J Macromol Sci C Polym Rev 45 263-287... 

As it is known [7] in semi crystalline polymers deformation process partial melting-recrystallization (mechanical disordering) of a crystalline phase can be realized, which is described quantitatively within the framework of a plasticity fractal theory [10], According to the indicated theory Poisson s ratio value at a yield point can be evaluated as follows ... 

For semi-crystalline polymers, it is different again the amorphous phases can deform in the manner described above, depending on whether the polymer is above or below the glass ttansition temperature, but the crystallites also deform plastically. Figure 9.4 shows how, initially, the crystallites shear in the direction of stress to align... 

Thomas, C., Seguela, R., Detrez, R, Miri, V., Vanmansart, C. Plastic deformation of spherulitic semi-crystalline polymers an in-situ AFM study of polybutene under tensile drawing. Polymer 50, 3714-3723 (2009)... 

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