CHARACTERIZATION OF THE MORPHOLOGIES AND NANOSTRUCTURES OF BLENDS OF POLY(STYRENE) LOCK-POLY(ETHENE-CO-BUT-1-ENE)-BLOCK-POLY(STYRENE) WITH ISOTACTIC AND ATACTIC POLYPROPYLENES BY TAPPING-MODE ATOMIC-FORCE MICROSCOPY

Blends of lock-poly(ethene-co-but-1-ene)-block-poly(styrene) (SEBS) wi th isotactic polypropylene (i-PP) and with atactic polypropylene (a-PP ) were prepared under different thermal treatments. On the basis of th e phase imaging of tapping-mode atomic force microscopy (TMAFM), we in vestigated the nanostructures and the morphologies of these blends as well as their dependence on blending history. The observed macrophase separation in i-PP/SEBS blends is caused by the incompatibility of the two polymer components. The microphase separation of the SEES compone nt depends on the thermal treatment. The morphology of a-PP/SEBS blend s exhibits domains that span a wide range of sizes from 15 mu m down t o 15 nm. Our work shows that TMAFM phase imaging is an important and c ompetitive tool for studying the microphase separation of polymers.