In situ near-infrared spectroscopic studies of the structural changes in polyethylene during tensile deformation

Structural and conformational changes occurring during tensile stretching of high-density, linear low-density, and low-density polyethylene materials were investigated with in-situ near-infrared (NIR) spectroscopy. Fragmentation releases the chain ends within crystalline lamellae and the cilia chains that are embedded in crystalline lamellae, and enables changes from the trans to gauche conformation. Meanwhile, the inclusion of co-monomers in the crystal lattice of linear low-density polyethylene causes the lamellar cluster to soften and stretch. Plastic deformation such as chain unfolding and slippage occurs within lamellar clusters.