Functional Star‐Like Polystyrenes as Organic Supports of MeDIP(2,6‐iPrPh)₂FeCl₂ Catalyst Toward Ethylene Polymerization

Abstract

Star‐like polystyrenes composed of a microgel core with functionalized arms have been designed and used as organic supports for a tridentate bis(imino)pyridinyl iron catalyst toward ethylene polymerization. In a first approach, star‐like polystyrenes bearing a few number of ethylene oxide units at the periphery of each arm have been prepared to immobilize, through nucleophilic interactions, common aluminum‐based activators [methylaluminoxane or trimethylaluminum (TMA)]. A second strategy is based on the synthesis of star‐like PS with arms ended either by a benzophenone or a benzoic acid function. Indeed, the reaction of TMA with these functional microgels leads to the in situ formation of alkoxide aluminum‐based species at the periphery of the star‐like microgels. All these functional PS microgels have been used as supports to immobilize and activate the MeDIP(2,6‐iPrPh)2FeCl2 catalyst toward ethylene polymerization. High catalytic activities and polyethylene beads of spherical morphology, constituted of polyethylene chains of monomodal molar mass distribution have been obtained, thanks to the organic support.

Polymer Microgels for Catalysis

“…Surface ligand star polymers were obtained from copper-catalyzed atom transfer radical polymerization (ATRP) of styrene and divinylbenzene with functional initiators carrying triethyleneglycol (SL8) (65), triethyleneglycol methyl ether (SL9) (65), benzophenone (SL10) (66,67), and benzoic acid (SL11) (67). Their star polymers were employed to support aluminum compounds [methylaluminoxane (MAO), and so on] for ethylene polymerization.…”

“…Metal-bearing microgels catalyzed various reactions (Fig. 5): oxidation of sec-alcohols (19,59), hydrogenation of ketones (58,60), asymmetric hydrogenation of ketone and imine (68)(69)(70), reduction of peroxide (71), living radical polymerization (61,62), and coordination polymerization of ethylene (65)(66)(67). Ruthenium complexes (72) are popularly encapsulated into microgels to result in versatile catalysts with high activity, practicability (catalyst recycle and product recovery), and tolerance to functional groups.…”

Change is the Only Constant

“…He et al [2] Extremely Color-Stable Blue Light-Emitting Polymers Based on Alternating 2,7-Fluorene-co-3,9-carbazole Copolymer Y. Cao et al [3] Tailored Branched Polyolefins by Metallocene Catalysis W. Kaminsky et al [4] Functional Star-Like Polystyrenes as Organic Supports of MeDIP(2,6-iPrPh) 2 FeCl 2 Catalyst Toward EthylenePolymerization H. Cramail et al [5] Synthesis of Functionalized NMP Initiators for Click Chemistry: A Versatile Method for the Preparation of…”

Silica/chitosan core–shell hybrid-microsphere-supported CuI catalyst for terminal alkyne homocoupling reaction

“…Ji et al [3] found apparent differences in the decomposition and reduction processes between unsupported and Al 2 O 3 -supported metal compounds only because of their different existing states. In Bouilhac's work, [5] the catalyst that was bound to a star-like polystyrene composed of a microgel core with functionalized arms showed high catalytic activities, and this special support structure contributed to the polystyrene's monomodal molar mass distribution. It is essential to choose suitable support materials with optimized structures for specific chemical reactions.…”

“…Thus, the core-shell supported catalyst with the catalyst on the shell is beneficial to take full advantage of the catalyst and obtain high yield in a short time. [5] Lin et al [17] prepared the Pd/SiO 2 @ZIF-8 core-shell catalyst and used it in the hydrogenations of alkenes. This core-shell catalyst exhibits selective, antipoisoning and antileaching properties.…”