A LATENT ENTANGLEMENT MODEL FOR THE DRAW OF SEMICRYSTALLINE POLYMERS

A novel molecular model, the latent entanglement, is proposed to expla in the relationships between ductilities of polyethylene reactor powde rs and different conditions of synthesis. According to Hoffman's varia ble cluster model, irregularities in the crystallite fold surface incr ease as the synthesis temperature is decreased. The concept of latent entanglement stems from the potentiality of these defects to convert i nto active entanglements when the involved chain segments are drawn ou t of the crystals.