Tensile deformation, HIPS

When ABS is compared to HIPS at comparable stress amplitudes, fatigue lifetimes are several decades higher. Several factors are involved. First, tensile strength and modulus of the SAN matrix are increased compared to values for the PS matrix. Secondly, the SAN matrix is more resistant to crazing and thirdly, the primary mode of deformation for ABS appears to be shear yielding rather than crazing. 

The TEM micrographs in Figs. 16a-16c of the undeformed regions of the reconstituted films prepared for mechanical tests revealed that particles were well dispersed and did not coagulate with each other. This proved that HIPS particles of narrow size ranges can be separated from a matrix and put into another matrix without coagulation and without particle deformation or disruption. The tensile stress-strain behavior of these samples is shown in Figs. 17a-17d, while in Table 3 the principal parameters of these curws are summarized. 

Fig. 11.2 Multiple crazing in mPS TEM micrograph of the ultrathin section of HIPS with salami particles of rubber and crazes at early stage of deformation. Arrow indicates tensile direction. Scale bar 1 pm (From Heckmann et al. (2005) reproduced with permission of Taylor and Francis)...

Fig. 5.68 Transmission electron micrographs of sections of deformed specimens of rubber-toughened polymers, (a) Stained section of a commercial HIPS. The small black particles are pigment (courtesy of Hu Xiao), (b) RTPMMA (courtesy, D. E. J. Saunders). The tensile axis is approximately vertical in each case.

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