Amphiphilic Triblock Copolymers Containing Polypropylene as the Middle Block

• Published in: Angewandte Chemie 2020-12, Vol.132 (51), p.23183-23188
• Main Authors: Yan, Tianwei, Guironnet, Damien
• Format: Article
• Language: English
• Subjects: Block copolymers; Chemical synthesis; Chemistry; Copolymerization; Copolymers; homogeneous catalysis; Insertion; Polymers; polyolefin; Polypropylene; postpolymerization modification; telechelic polypropylene
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.202009165

The synthesis of stereoregular telechelic polypropylene (PP) and their use to access triblock amphiphilic copolymers with the PP block located in the center is described. The strategy consists of selectively copolymerizing propylene and a di‐functional co‐monomer (1,3‐diisopropenylbenzene) to yield a α,ω‐substituted polypropylene. Initiation of the copolymerization favors insertion of DIB over propylene; propagation steps favor insertion of propylene. Termination via a chain‐transfer reaction yields the terminal unsaturation of the polymer. The telechelic polypropylene is then converted into α,ω‐hydroxyl‐terminated polypropylene and used as a macroinitiator for the synthesis of triblock copolymers. Water‐soluble amphiphilic triblock polymers are also synthesized. The use of catalytic reactions simultaneously provides the stereocontrol of the polypropylene and high productivity (multiple chains of block copolymer per metal center). Telechelic isotactic polypropylene is synthesized through selective copolymerization of propylene and di‐functional co‐monomer. Following a series of post‐polymerization modifications, including the ring‐opening polymerization of tert‐butyl glycidyl ether, water‐soluble polypropylene‐containing triblock copolymers are synthesized and characterized.