Property modification of an inorganic surface can be readily achieved
through the use of macromolecules chemically grafted to the surface at
specific functional sites along the chain. While numerous efforts hav
e addressed the properties of linear chains rafted at one end (tails),
relatively few have extended such studies to include double-tethered
chains (loops). In this work, we consider loop/tail mixtures in which
both chain species possess an identical number of repeat units. Bond-f
luctuation simulations have been performed to ascertain the effects of
composition, chain length and surface density on the segmental densit
y distribution and layer height of each constituent species and of the
mixture. These results compare favourably with self-consistent field
predictions for bidisperse mixtures of grafted tails differing in leng
th by a factor of two. (C) 1998 Elsevier Science Ltd. All rights reser
ved.