SCALING PROPERTIES AND ORDERING PHENOMENA OF STAR POLYMERS IN SOLUTION

Star polymers are prototype systems both for tethered chains as well a s for branched polymers. In this study we present a thorough investiga tion of the single star form factors in dilute solutions spanning a ra nge of functionalities from 8 to 128. Using the zero average contrast method the form factor determination was also extended into the semidi lute regime. As a consequence of their very inhomogeneous monomer dens ity distribution star polymers exhibit osmotic repulsion leading to or dering phenomena in the neighborhood of the overlap concentration. We present a detailed investigation of such ordering phenomena in star po lymer solutions with varying functionality and molecular weight. In al l cases we observe an interparticle structure factor which is most pro nounced at the overlap concentration phi. The ordering tendency incre ases with increasing functionality. These results are compared with cu rrent theoretical predictions.