Premium
Simulation of tubular low‐density polyethylene
Author(s) -
Gupta Santosh K.,
Kumar Anil,
Krishnamurthy M. V. G.
Publication year - 1985
Publication title -
polymer engineering and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.503
H-Index - 111
eISSN - 1548-2634
pISSN - 0032-3888
DOI - 10.1002/pen.760250108
Subject(s) - dispersity , materials science , branching (polymer chemistry) , monomer , polyethylene , polymer , kinetic energy , kinetic scheme , polymer chemistry , chemical engineering , thermodynamics , composite material , physics , quantum mechanics , engineering
The simulation of tubular, high‐pressure low‐density polyethylene reactors is performed using a comprehensive kinetic scheme which includes branching reactions as well as reactions leading to vinyl and vinylidene group formation. The variation of the physical properties of the reaction mass with position has been accounted for. In addition to predicting the conversions of the monomer and initiator, the temperature, and the number‐average molecular weight, this study enables the computation of the polydispersity index and the concentration of vinyl, vinylidene, and methyl groups as a function of position. These have important implications in terms of product properties. Detailed simulations have shown that the steady‐state approximation can be used for obtaining the concentrations of the initiator and the polymer radicals. In addition, some simple closure conditions have been established. The effect of multiple intermediate feeds is also investigated and it is found that under certain operating conditions the reactor performance becomes inherently unstable.