(163d) Model Development for Copolymerization Process of Ethylene and Norbornene At Elevated Pressure

Model
Development for Copolymerization Process of Ethylene and Norbornene Copolymer
at Elevated Pressure

Zhen
Yao*, Binbin Dai , Bing Xie, Kun
Cao

¹ State Key Laboratory of Chemical Engineering(ZJU), Institute of Polymerization
and Polymer Engineering, Department of Chemical Engineering, Zhejiang University,
Hangzhou 310027, China

Process model for ethylene and
norbornene(NB) copolymerization at elevated pressure were developed by
considering the variation of active site concentration and the influence of mass
transfer process. The parameters were validated by batch polymerization. The
polymerization experiment was taken place in a 2L agitated reactor, in which the effect of mass
transfer process on ethylene and norbornene concentration can not be
ignored. As a result, a physical model for mass transfer process was provided. It
is assumed that a concentration gradient is limited in numerous spherical
regions which take the catalyst active site as its centre after the reaction
starts. Besides, as norbornene has a negative affect on catalyst activation, a
relationship between the catalyst active site concentration and the norbornene
concentration was developed. The polymerization rate, copolymer composition
and ethylene dissolving rate were predicted and compared with the experimental
data. Further calculation on the viscosity and the instantaneous NB/E monomer
ratio were developed. The copolymer composition distribution(CCD)
was predicted and compared with the copolymer characteristic results. Finally,
by using designed policy to vary ethylene pressure, copolymers with narrow CCD
were produced.