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Synthesis of Poly(?-caprolactone)-Based Miktoarm Star Copolymers through ROP, SA ATRC, and ATRP.

ABSTRACT: The synthesis of novel branched/star copolymers which possess unique physical properties is highly desirable. Herein, a novel strategy was demonstrated to synthesize poly(?-caprolactone) (PCL) based miktoarm star (?-star) copolymers by combining ring-opening polymerization (ROP), styrenics-assisted atom transfer radical coupling (SA ATRC), and atom transfer radical polymerization (ATRP). From the analyses of gel permeation chromatography (GPC), proton nuclear magnetic resonance (¹H NMR), and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), well-defined PCL-?-PSt (PSt: polystyrene), and PCL-?-PtBA (PtBA: poly(tert-butyl acrylate) ?-star copolymers were successfully obtained. By using atomic force microscopy (AFM), interestingly, our preliminary examinations of the ?-star copolymers showed a spherical structure with diameters of ca. 250 and 45 nm, respectively. We successfully employed combinations of synthetic techniques including ROP, SA ATRC, and ATRP with high effectiveness to synthesize PCL-based ?-star copolymers.

SUBMITTER: Sathesh V

PROVIDER: S-EPMC6403792 | biostudies-literature |

REPOSITORIES: biostudies-literature

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