Propylene polymerization in a semibatch reactor. Analysis of soluble metallocene catalyst behavior through reactor modeling

Abstract

We study the process involved in metallocene activation and further propylene polymerization. In this paper, we begin by analyzing the behavior of soluble metallocene in propylene polymerization before advancing to the study of the heterogeneous polymerization. Experimental data obtained in a semibatch laboratory polymerization reactor using ethylenbisindenylzirconium dichloride (EtInd2ZrCl2)/ methylaluminoxane (MAO) are combined with a mathermatical model providing useful information such as number of active sites and their activation patterns. We present a mathematical model for the reactor that predicts not only reactor productivity but also the molecular properties of the product. We apply the model to soluble systems in order to find the optimal parameters for the catalyst itself and in the presence of different types of additives such as aluminum chloride (AlCl3) and ethyl benzoate (E.B.).

Theoretical and Spectroscopic UV Study of the EtInd2ZrCl2/MAO, EtInd2ZrCl2/MAO-AlCl3 and EtInd2ZrCl2/MAO-Ethyl Benzoate Interaction

“…We checked this point with results from modeling of our experimental kinetics curves (see the literature [51,52] ). This type of site would suffer second order deactivation by bimolecular reaction with methane evolution and Zr1CH 2 1Zr bond formation with other site 1.…”

“…Simulation of propylene semibatch polymerization kinetics from our group [51,52] show that the deactivation constant of the site with first order deactivation is strongly affected by additives, whereas the deactivation constant of the site with second order deactivation is not. If the sites of second order deactivation are considered to be LCIPs and the additives change the Zr electrophilicity, it is easy to think as these sites as the most active.…”

Preparation method of superactive Ziegler–Natta catalysts to produce ultra-high molecular weight amorphous poly(1-octene), poly(1-decene), and their copolymers

“…The polymers produced by single-center metallocene catalysts have low molecular weight with narrow molecular weight distribution [15][16][17][18][19]. However, the productivity of a metallocene catalyst is over a period of 60 min and after this time their activity deteriorates significantly, whereas by Ziegler-Natta catalysts, ultra-high molecular weight polyolefins can be produced [6,7,20].…”

New Approach in Modeling of Metallocene‐Catalyzed Olefin Polymerization Using Artificial Neural Networks

“…Earlier, it was conventional to obtain the rate constants from time average reaction rates and final molecular weights, [1][2][3][4][5] while in recent models, instantaneous reaction rates are being used. [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] In these methods, the algebraic function, developed for desired output [7][8][9] (like polymerization rate)…”