Homogeneous Group IVB Catalysts of New Generations for Synthesis of Ethylene-Propylene-Diene Rubbers: A Mini-Review

Abstract

Ethylene-propylene-diene rubbers (EPDM) are one of the most important polyolefin materials widely commercialized and used in various industries in recent years. The production of EPDM is based solely on catalytic coordination polymerization processes. The development of new catalysts and processes for the synthesis of EPDM has expanded the range of products and their manufacturing in terms of energy efficiency, processability, and environmental safety. This mini-review mainly analyzes patented data on the synthesis of EPDM on new-generation single-site catalytic systems based on Group IVB complexes including the systems commercialized by major manufacturers of EPDM. The advantages of these systems are evident in comparison with conventional vanadium systems introduced into production in the 1960s and used to date in the industrial synthesis of EPDM.

Imidazolidin-2-iminato vanadium complexes for the synthesis of ethylene/propylene/5-ethylidene-2-norbornene (ENB) terpolymers with high ENB incorporation and ultra-high molecular weight

“…Catalysts occupy an important position in the control of the copolymerization ability and molecular weight of the resulting EPDMs in the coordination polymerization of ethylene, propylene and non-conjugated dienes. 7,[26][27][28][29][30][31] In this regard, the development of new catalytic systems allowing for the preparation of EPDM with ultra-high molecular weight and high ENB content is essential. Of the abundant catalysts, vanadium complexes present particularly good copolymerization ability in ethylene/propylene copolymerization, affording ethylenepropylene copolymers with high molecular weight.…”

Synthesis and Properties of Ethylene/propylene and Ethylene/propylene/5-ethylidene-2-norbornene Copolymers Obtained on Rac-Et(2-MeInd)2ZrMe2/Isobutylaluminium Aryloxide Catalytic Systems

“…Ethylene/propylene and ethylene/propylene-diene rubbers (also called as EPM and EPDM) are important elastomeric polymers widely used in cars, cables, construction, and other industries [ 1 , 2 , 3 , 4 , 5 ]. These elastomeric materials are used as materials showing excellent resistance to heat, air, ozone, and steam, and are able to operate in a wide temperature range (from −50 to +130 °C).…”

“…The most effective and modern precatalysts are metallocenes and post-metallocenes activated by methylalumoxane (MAO). Notable species are metallocenes [ 2 , 3 , 8 , 9 , 10 , 11 , 12 ], constrained geometry complexes [ 2 , 3 , 13 , 14 , 15 ], titanium half-sandwiches with donor nitrogen-containing ligands [ 2 , 3 , 4 , 13 , 16 ], and aryloxy-ether zirconium or hafnium complexes [ 2 , 3 , 17 ]. Some precatalysts have become the basis of novel technologies such as Keltan ACE and AMC (Advanced Molecular Catalyst) [ 2 , 3 , 16 , 17 ].…”

“…Notable species are metallocenes [ 2 , 3 , 8 , 9 , 10 , 11 , 12 ], constrained geometry complexes [ 2 , 3 , 13 , 14 , 15 ], titanium half-sandwiches with donor nitrogen-containing ligands [ 2 , 3 , 4 , 13 , 16 ], and aryloxy-ether zirconium or hafnium complexes [ 2 , 3 , 17 ]. Some precatalysts have become the basis of novel technologies such as Keltan ACE and AMC (Advanced Molecular Catalyst) [ 2 , 3 , 16 , 17 ]. The discovery of new suitable complexes and the novel means of their activation could lead to new and possibly much cheaper processes for the production of EPDM with a wide spectrum of properties [ 2 , 3 ].…”

“…Some precatalysts have become the basis of novel technologies such as Keltan ACE and AMC (Advanced Molecular Catalyst) [ 2 , 3 , 16 , 17 ]. The discovery of new suitable complexes and the novel means of their activation could lead to new and possibly much cheaper processes for the production of EPDM with a wide spectrum of properties [ 2 , 3 ].…”