The lamellar crystal structures are connected through amorphous polymer segments: the tiechains. The probability of tie chain formation increases with the polymer chain length. Tie chainmolecules are known to increase toughness and ESCR or long-term creep properties, by “tie-ing”multiple crystals together. Tie chains show extensibility and mobility and can as such absorb anddissipate energy. This is graphically presented in Graphic 2.