关键词: desorption model;mass transfer rate;polyethylene

Abstract: In this paper the desorption kinetics of volatile in condensed modepolyethylene process is
studied through experiments. It is found thatthough the residual volatile in particles at
the later stage of desorptionaccounts for a relatively small portion of the total quantity,
the desorptionof this part of volatile requires much longer time than at the earlier
stage.For high requirement of devolatilization, the total time needed will bepredominately
determined by the residual amount of volatilein particles. Temperature has greater effect
on the desorption rate thanother influence factors, especially in the later period of
desorption.A model is proposed to calculate the volatile desorption rate for condensedmode
polyethylene process.

Key words: desorption model, mass transfer rate, polyethylene