The isothermal crystallization behavior of thin films of isotactic pol
y(propylene) between plates coated with chromium, Teflon (R) or gold i
s studied by polarized light microscopy. At all contact surfaces betwe
en poly(propylene) and the other materials, transcrystallinity can be
observed and competes with the growth of entities which originate in t
he bulk phase. The shape of these entities can be described by two int
ersecting paraboloids.