Isoprene chain shuttling polymerisation between cis and trans regulating catalysts: straightforward access to a new material

Abstract

Isoprene chain shuttling polymerisation between the 1,4-trans regulating Cp*La(BH)(THF)/MgBuEt (Cp* = CMe) and the 1,4-cis regulating NdCl(THF)/AlR (R = Et or Bu) systems provides access to stereoblock polyisoprene. Under selected experimental conditions, the trans segments are semi-crystalline, leading to a thermoplastic elastomer-like material.

Thiol‐Ene Cationic and Radical Reactions: Cyclization, Step‐Growth, and Concurrent Polymerizations for Thioacetal and Thioether Units

“…Furthermore, if those different reactions occur simultaneously, the polymer properties can be arbitrarily tuned by the reactions. Indeed, in chain‐growth polymerizations, a single monomer is polymerized simultaneously through multiple propagating species with different stereo‐ or regioselectivities, resulting in unique polymers, such as random, gradient, and block or multiblock structures, which cannot be obtained by repetitive single reactions . In addition, concurrently occurring polymerizations of common monomers by different propagating species such as radicals, cations, and anions are attractive because they can dramatically widen the scope of accessible polymer structures with novel and/or tunable properties …”

“…Furthermore,ifthose different reactions occur simultaneously,t he polymer properties can be arbitrarily tuned by the reactions.I ndeed, in chain-growth polymerizations,asingle monomer is polymerized simultaneously through multiple propagating species with different stereo-or regioselectivities, resulting in unique polymers,s uch as random, gradient, and block or multiblock structures,w hich cannot be obtained by repetitive single reactions. [2][3][4][5][6][7][8][9] In addition, concurrently occurring polymerizations of common monomers by different propagating species such as radicals,c ations,a nd anions are attractive because they can dramatically widen the scope of accessible polymer structures with novel and/or tunable properties. [10][11][12][13][14][15][16][17][18] Athiol and olefin usually undergo radical addition, that is, at hiol-ene reaction, which is one of the most efficient and robust click reactions,e ither in the presence of ar adical initiator or under UV irradiation to result in the anti-Markovnikov adduct with high selectivity and high yield.…”

Thiol‐Ene Cationic and Radical Reactions: Cyclization, Step‐Growth, and Concurrent Polymerizations for Thioacetal and Thioether Units

“…Furthermore, if those different reactions occur simultaneously, the polymer properties can be arbitrarily tuned by the reactions. Indeed, in chain‐growth polymerizations, a single monomer is polymerized simultaneously through multiple propagating species with different stereo‐ or regioselectivities, resulting in unique polymers, such as random, gradient, and block or multiblock structures, which cannot be obtained by repetitive single reactions . In addition, concurrently occurring polymerizations of common monomers by different propagating species such as radicals, cations, and anions are attractive because they can dramatically widen the scope of accessible polymer structures with novel and/or tunable properties …”

Intelligent Monte Carlo: A New Paradigm for Inverse Polymerization Engineering

“…In the current study, chain shuttling polymerization has been chosen as a challenging and intricate polymerization system to test the proposed IMC simulation approach. [7,[31][32][33] In the process represented in Scheme 1, the growing macromolecular chain is able to shuttle between two catalysts showing a significantly different reactivity versus ethylene and 1-octene, the two comonomers. [5] The trans-metallation reaction occurs via a chain shuttling agent (CSA).…”