End defects in crystalline polyethylene. 1. Statement of the problem and modeling of the steric structure of end defects

Conclusions 1. Changes in the conformations of polyethylene molecules around the end of a neighboring chain and around the ends of two neighboring chains have been determined on an electronic calculator for various directions of end bending.2. It has been ascertained that a column of bivacancies disappears with simultaneous formation of spiral dislocations at smaller distances from the chain end to the crystallite surface than in the case of a single-vacancy column.3. Energies of formation of end defects and the bonding energy of defects upon aggregation have been calculated.Institute of Polymer Mechanics, Academy of Sciences of the Latvian SSR, Riga. Translated from Mekhanika Polimerov, No. 3, pp. 400–407, May–June, 1978.