Styrene was recovered from polystyrene (molecular weight of 138,000) b
y thermolysis in a nitrogen atmosphere at temperatures between 368 and
407 degrees C. The results were independent of the initial weight of
polystyrene, which was varied between 30 and 480 g. Up to 90% of the p
olystyrene was converted to liquid products. The liquid products had a
styrene concentration as high as 90% and the styrene yield increased
with temperature. Above 390 degrees C, the residue left in the reactor
(less than 30% of initial polystyrene charge) consisted mainly of sty
rene monomer, dimer, and trimer (MW of 190). The kinetics support a fi
rst-order reaction with regard to the rate of production of volatiles.
The activation energy was es estimated to be 166.5 kJ/mol. (C) 1995 J
ohn Wiley & Sons, Inc.