EPITAXY OF HELICAL POLYOLEFINS

The structural rules which govern the epitaxial crystallisation of pol ymers - and especially polyolefins - on organic substrates are establi shed. Illustrative examples involve isotactic and syndiotactic polypro pylenes and poly(1-butene). Investigation of the film structure by ele ctron microscopy, electron diffraction and atomic force microscopy rev eals some unprecedented features, including in particular the selectio n of the contact plane according to the chirality of its constituent h elices, and direct observation of both right and left hands of polyole fin helices.