We report for the first time by computer simulations, evidence of poly
mer chain collapse near a lower critical solution temperature (LCST).
Continuous space, Monte Carlo simulations have been performed on freel
y jointed, Lennard-Jones chains in a LJ monomeric solvent with symmetr
ic energetics. The LCST phase boundary and associated chain collapse i
n the supercritical solvent region has been established for chains of
size 20. This Letter focuses on why the chain collapses near a LCST. (
C) 1997 Published by Elsevier Science B.V.