“Pulsed” Chain Transfer Anionic Polymerization: A Green and Cost‐Effective Approach for Controlled Polymer Synthesis DOI Open Access
Jian Tang, Yudong Liu, Jinhui Liu

et al.

Angewandte Chemie, Journal Year: 2025, Volume and Issue: unknown

Published: March 10, 2025

Abstract Herein, we report a method that significantly enhances the atom economy of catalysts in living polymerization. By introducing intermittent, switchable chain‐transfer reactions during polymerization process, multiple regenerations catalyst are achieved while preserving “living”/controlled characteristics. The specially designed catalytic system, composed 1,2‐dipyrrolidinoethane/n‐butyllithium/n‐butylpotassium/toluene, exhibits rate is highly sensitive to temperature. It enables at low temperatures, high rapid chain transfer toluene occurs. Utilizing this characteristic, initially carried out temperatures; once monomer consumed, increasing temperature promotes transfer, resulting initiator regeneration. regenerated can then initiate new cycles upon addition fresh monomers. This process was repeated for more than dozen cycles, achieving an efficiency up 1500%. Using method, successfully synthesized polybutadiene and styrene‐butadiene copolymer with extremely narrow molecular weight distribution ( Đ = 1.1). mechanism investigated by situ NMR spectroscopy, MALDI‐TOF‐MS, DFT calculations. approach particularly well‐suited controllable, green, cost‐effective production low‐ medium‐molecular‐weight polymers block copolymers.

Language: Английский

Stereoblock polymerization of dienes in switching stereoselectivity by addition of MMAO cocatalyst DOI
Zhongyang Tan, Lixia Tian, Wenjie Zheng

et al.

Journal of Macromolecular Science Part A, Journal Year: 2025, Volume and Issue: 62(2), P. 118 - 125

Published: Jan. 2, 2025

Hard-soft polydienes copolymers were synthesized by one-pot sequential polymerization with neodymium-based catalyst. trans-1,4 polybutadiene (TPB) was firstly obtained the coordinative chain transfer (CCTP) of 1,3-butadiene (BD) Nd(Oi-Pr)3/Mg(n-Bu)2 Diblock crystallizable TPB segment and soft cis-1,4 specific achieved addition BD/isoprene (IP) MMAO to polymerzaition system. The length each block microstructure copolymer are controllable adjusting monomer feed ratio. exhibits both glass transition temperature (Tg) originating from blocks melting point (Tm) hard TPB, respectively. Moreover, incorporation cis-1,4-PB could improved mechanical properties cold-flow phenomenon relieved.

Language: Английский

Citations

0
“Pulsed” Chain Transfer Anionic Polymerization: A Green and Cost‐Effective Approach for Controlled Polymer Synthesis DOI Open Access
Jian Tang, Yudong Liu, Jinhui Liu

et al.

Angewandte Chemie International Edition, Journal Year: 2025, Volume and Issue: unknown

Published: March 10, 2025

Herein, we report a method that significantly enhances the atom economy of catalysts in living polymerization. By introducing intermittent, switchable chain-transfer reactions during polymerization process, multiple regenerations catalyst are achieved while preserving "living"/controlled characteristics. The specially designed catalytic system, composed 1,2-dipyrrolidinoethane/n-butyllithium/n-butylpotassium/toluene, exhibits rate is highly sensitive to temperature. It enables at low temperatures, high rapid chain transfer toluene occurs. Utilizing this characteristic, initially carried out temperatures; once monomer consumed, increasing temperature promotes transfer, resulting initiator regeneration. regenerated can then initiate new cycles upon addition fresh monomers. This process was repeated for more than dozen cycles, achieving an efficiency up 1500%. Using method, successfully synthesized polybutadiene and styrene-butadiene copolymer with extremely narrow molecular weight distribution (Đ = 1.1). mechanism investigated by situ NMR spectroscopy, MALDI-TOF-MS, DFT calculations. approach particularly well-suited controllable, green, cost-effective production low- medium-molecular-weight polymers block copolymers.

Language: Английский

Citations

0
“Pulsed” Chain Transfer Anionic Polymerization: A Green and Cost‐Effective Approach for Controlled Polymer Synthesis DOI Open Access
Jian Tang, Yudong Liu, Jinhui Liu

et al.

Angewandte Chemie, Journal Year: 2025, Volume and Issue: unknown

Published: March 10, 2025

Abstract Herein, we report a method that significantly enhances the atom economy of catalysts in living polymerization. By introducing intermittent, switchable chain‐transfer reactions during polymerization process, multiple regenerations catalyst are achieved while preserving “living”/controlled characteristics. The specially designed catalytic system, composed 1,2‐dipyrrolidinoethane/n‐butyllithium/n‐butylpotassium/toluene, exhibits rate is highly sensitive to temperature. It enables at low temperatures, high rapid chain transfer toluene occurs. Utilizing this characteristic, initially carried out temperatures; once monomer consumed, increasing temperature promotes transfer, resulting initiator regeneration. regenerated can then initiate new cycles upon addition fresh monomers. This process was repeated for more than dozen cycles, achieving an efficiency up 1500%. Using method, successfully synthesized polybutadiene and styrene‐butadiene copolymer with extremely narrow molecular weight distribution ( Đ = 1.1). mechanism investigated by situ NMR spectroscopy, MALDI‐TOF‐MS, DFT calculations. approach particularly well‐suited controllable, green, cost‐effective production low‐ medium‐molecular‐weight polymers block copolymers.

Language: Английский

Citations

0