Continuous flow synthesis of core cross-linked star polymers via photo-induced copper mediated polymerization. Issue 13 (22nd February 2019)

• Record Type: Journal Article
• Authors: Vrijsen, Jeroen H.; Osiro Medeiros, Camila; Gruber, Jonas; Junkers, Tanja
• Is Part Of: Polymer chemistry. Volume 10:Issue 13(2019)
• Page Start: 1591
• Page End: 1598
• Publication Date: 2019-02-22
• Subjects: Polymers -- Periodicals; Macromolecules -- Periodicals; Polymerization -- Periodicals; 547.705
• DOI: 10.1039/c9py00134d
• Languages: English
• ISSNs: 1759-9954

Abstract

Abstract : A convenient method to synthesize core cross-linked star polymers via a continuous flow photopolymerization process is developed. Abstract : A convenient method to synthesize core cross-linked star polymers via a continuous flow photopolymerization process is developed. Photo-induced copper mediated radical polymerization was employed for arm and star syntheses. The arms of the core cross-linked star polymers are composed of poly(methyl acrylate) (with a M n, arm of 2600 or 4700 g mol −1, Đ arm ≈ 1.12), and 1, 4-butanediol diacrylate was used as the core cross-linker. Flow polymerization enables the rapid formation of star polymers (15–20 minutes, M w, star flow = 170 400 g mol −1, 33 arms). Furthermore, a reactor cascade was built that combines arm and star syntheses without the isolation of the intermediate product between both reactor stages. In this way, the star polymer is formed ( M w, star = 156 500 g mol −1, 34 arms) in a one-pot fashion, yet under scalable conditions. Surface functionalized star polymers were obtained with similar molecular weights via alcohol-functional initiators. Finally, a flow reactor setup is demonstrated that allows direct access to miktoarm star polymers. In there, two different arms are synthesized from photopolymerization in parallel and then simultaneously fed into a third reactor. The resulting miktoarm core cross-linked star polymers are composed of poly(methyl acrylate) and poly(benzyl acrylate) arms ( M w, star = 189 300 g mol −1, 33 arms). The reactor cascade enables rapid star polymer formation in a continuous process (within 40 minutes, when reactor conditions are stable) without intermediate purification, improved illumination and facile upscaling.