DIRECT OBSERVATION OF RIGHT AND LEFT HELICAL HANDS OF SYNDIOTACTIC POLYPROPYLENE BY ATOMIC-FORCE MICROSCOPY

Syndiotactic polypropylene (sPP), epitaxially crystallized on p-ter- or p-quaterphenyl is investigated by electron microscopy and diffraction and atomic force microscopy (AFM). The epitaxial relationship between the be contact face of sPP and the substrate (001) place is established. In the be contact plane, the sPP helices display a succession of CH3, CH2, and CH3 groups tilted at 45 degrees to the helical axes. These groups have been visualized by AFM in a liquid cell, thus providing the first direct observation, in unfiltered images, of arrays of both right and left hands of individual polyolefin helices embedded in their crystallographic environments.