A stroboscopic X-ray apparatus for the study of the kinetics of strain-induced crystallization in natural rubber

Insight into unique deformation behavior of oriented isotactic polypropylene with branched shish-kebabs

“…For the sake of simplicity, the engineering stress-strain curve of BSK iPP sample is divided into four distinct regions, designated as I, II, III and IV, corresponding to the initial linear elastic, yielding, necking (post-yielding), and very early stage of strain hardening region, respectively. It is seen that Normal iPP sample falls into a typical stress-strain curve of semicrystalline polymers [42,45,46], while BSK iPP sample is totally different, exhibiting a less declined stress in the necking region. Due to the presence of BSK structure, the BSK iPP samples exhibit a higher drawing stress than Normal iPP samples throughout the entire deformation process.…”

Multiaxial deformation and strain-induced crystallization around a fatigue crack in natural rubber

“…Furthermore, it is to note that the frequency decrease (from 2 to 0.1 Hz) applied to perform the acquisition and the mapping might have a slight effect on the observed results. Recent studies dealing with the kinetics of SIC [21][22][23] have highlighted that the crystallization characteristic time in NR is short, around 20 ms according to Candau et al [21], which is much smaller than the duration of a half fatigue cycle at 2 Hz (250 ms). It means that SIC still exists at 2 Hz especially when the distance to the crack tip is reduced because the stretch ratios are very high.…”

Kinetics of strain-induced crystallization in natural rubber: A diffusion-controlled rate law

“…Using a stroboscopic technique, several studies showed that the crystallinity under cyclic dynamic conditions is lower in comparison to the same strain under static conditions [4,5,6,7,8]. In our previous works, we followed the strain-induced crystallization under dynamic cyclic loading in real time and showed that the crystallinity at a crack tip is reduced under dynamic load [3,9].…”