Abstract: | In this paper the validity of the well-known Roedel's “back-biting” mechanism is questioned. It is shown that number and type of branches depend on the degree of order (entropy) of compressed ethylene molecules. A new mechanism for the short chain branching in low density polyethylene is proposed, based on the effect of the supermolecular species in compressed ethylene in this reaction. An equation for calculation of the number of branches for ethylene polymerization in a wide range of temperature (?5 to + 200°C) and pressure (40 to 7000 atm) is given. |