The Catalyst Review November 2019 - 11

SPECIAL FEATURE
WR Grace, a premier PP technology licensor and catalyst provider, commercializes CONSISTA C 601 PP catalyst using a substituted
phenylene aromatic diester internal donor. It is a drop-in phthalate-free catalyst system with improved product properties, including
high melt flow grades that avoid visbreaking, higher yield, higher hydrogen response, high selectivity/low xylene extractables,
excellent impact/stiffness balance and a broader MWD. Most of the R&D activities of Grace are dedicated to find alternative internal
donor to phthalate. Many patents are covering a mixture of two donors that are giving excellent results with a good balance of
activity and stereospecificity control: the two donors are 3-methyl-5-tert butyl-1, 2 phenylene dibenzoate and naphthalene-1, 8-diyl
dibenzoate. Grace is exploring other molecules as internal donors with mixed success. Grace has an excellent PP catalyst technology
(Polytrak) based on phthalate; these new internal donors implemented on Polytrak technology could give a tremendous advantage
to Grace.
Sinopec, in cooperation with its research institute BRICI, wants to position itself as a global supplier of catalysts and technologies.
Sinopec is constantly refining its catalysts to compete better with the other catalyst suppliers. The catalysts described in the
patents of BRICI have exceptional attributes, like very high activity and high stereospecificity. The main Sinopec activities regard the
improvements of Ziegler Natta catalysts, specifically in preparation of spherical support needed for different PP process and use of
phthalate-free internal donors in the way to have drop in ZN catalysts and to improve diether catalyst.
Regarding the above improvements, Sinopec's main activities are: a) Preparation of spherical support needed for different PP
processes. The granulometry of the catalyst dictates, by the replica effect, the granulometry of the PP powder (which is critical
to guarantee stable operation and minimize plant down time for plugging or fouling); and b) use of other donors than phthalate.
Reviewed patents are clearly showing the depth of innovation at BRICI (patents claims are supported by thousands of experimental
results) and Sinopec catalysts are, according to the experimental data, unequaled in term of activity and stereospecificity. As new
internal donor di-imines is used in combination with phthalates or diethers. The mixture of the two internal donors provides a
solution to various problems experienced with diether catalyst without losing answer to H2. The resin MWD is broader, the stereo
specificity of the catalyst is high, and the catalyst has a long lifetime and a high activity. In addition, another new internal donor
based on the reaction of a diol ester with benzoic acid is patented. Sinopec could become a major PP catalyst player if would satisfy
the critical needs of its potential customers for supply chain and constancy of quality.
Polymers of ethylene, propylene and a non-conjugated diene (EPDM) represent an important class of elastomers commercially
applied, usually in slurry, solution or gas phase processes. Specialized catalysts are used to polymerize the monomers into controlled
polymer structures. Since their introduction, ethylene-propylene elastomers (EPR) and EPDM rubber are commercially produced
using homogeneous catalysts as vanadium-based ZN catalysts or, more recently, well-defined, highly active, homogeneous catalysts,
such as classical metallocenes and other advanced post-metallocene single-sites catalysts (SSC), targeted at production of new types
of EP elastomers with fast cure and high degrees of cure at very high yields. A disadvantage so far using conventional vanadium
catalysts for EPDM, results in the formation of very large branched molecules in the polymerization reactor, leading to gel formation
and ultimately to blockage and shutdown.
Lanxess/Arlanxeo (spin off rubber business from Bayer) has further developed and especially tailored for EPDM production a new
class of catalysts, which are extremely productive, named Keltan ACE (Advanced Catalyst Elastomers). For this improvement project,
Lanxess made use of High Throughput Experimentation (HTE) technology and equipment to allow for fast screening of catalyst
configuration and fundamental understanding of the improved catalyst technology. Lanxess has patented several enhancements
related to ACE catalysts (e.g., Van Doremaele 2016, 2017). This invention relates to a new catalyst system for the polymerization of
olefins comprising a metal complex of formula CyLMD and an activating cocatalyst, wherein M is titanium, Cy is a cyclopentadienyltype ligand, L is an imine ligand, D is a diene.
The new catalyst system has a substantially improved heat stability, allowing higher reactor temperatures and very high catalyst
productivity that enables the elimination of the catalyst removal step. The ACE catalyst system allows for the production of a
complete EPDM grade portfolio with products that perform identical to EPDM grades, produced by ZN catalysts, but with a reduced
environmental impact. In addition, the ACE catalyst technology creates opportunities to develop products that are not attainable
with classical ZN or state-of-the-art metallocene catalyst technologies, like high molecular weight high VNB (vinyl norbornene)
EPDMs.
Dow Elastomers commercialized successful EPDM products under the name Nordel at the end of the '90s through a new production
platform representing the fusion of two new technologies, a metallocene catalyst used with the gas phase process, to make a
distinguished powdered product. Dow Elastomers has persisted in its breakthrough innovation policy arriving to the current
Advanced Molecular Catalyst that offers even greater efficiency and improved performance across a broader range of applications
The Catalyst Review

November 2019

The Catalyst Review November 2019

Table of Contents for the Digital Edition of The Catalyst Review November 2019