DIAMOND LATTICE MODEL OF SEMICRYSTALLINE POLYETHYLENE IN THE AMORPHOUS REGION

The statistics of polyethylene chains in the amorphous region between two crystallites have been computed, modeling the chains as random wal ks on a diamond lattice with two absorbing boundaries. The probabiliti es of trans and gauche states are considered, thereby determining some effects of temperature, e.g. at higher temperature more loops are for med and the average length of loops is shorter, in contrast to less ti es formed with a longer average length. It is found that the lower bou nd on the adjacent reentry is 79% at very high temperature and it incr eases to 81% at about 400 K. (C) 1998 American Institute of Physics. [ S0021-9606(98)50213-9].