The mesomorphic form of poly(ethylene terephthalate), present in sampl
es drawn at 60 degrees C at a draw ratio of 4, was studied by analysin
g the transport properties of dichloromethane vapours. The reduced sor
ption with respect to the amorphous sample indicates that the mesophas
e is impermeable to the vapours at low activity, and this allows the d
etermination of the fraction of mesophase in the drawn samples. Copyri
ght (C) 1996 Elsevier Science Ltd.