Effect of 110Â keV electrons on the deformation mechanisms of low density polyethylene

The deformation mechanisms of low density polyethylene (LDPE) irradiated by 110 keV electrons with different fluences are discussed basing on the deformation behaviors and the structural evolution during uniaxial tensile deformation. The structural evolution is in-situ obtained from small angle X-ray scattering (SAXS) and wide angle X-ray diffraction (WAXD). It is found that the 110 keV electrons with low fluence change the transition strains of different regions (strain-hardening region, strain-softening region, secondary strain-hardening region, plateau in the strain-softening region and sub-stages in the second strain-hardening region) for LDPE. The 110 keV electrons with high fluence lead to disappearance of the strain-softening region and quick break of the samples. From SAXS and WAXD analyses, it is known that the 110 keV electrons have no effect on the disintegration of the original lamellae and the rotation of the lamellae, only slow down the formation of the new crystals. It is concluded that the crosslinking strengthening generated by 110 keV electrons is the dominant reason for the changes of the deformation behaviors of LDPE.