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  • Block copolymers containing stable radical and fluorinated blocks with long-range ordered morphologies prepared by anionic polymerization
Title: Block copolymers containing stable radical and fluorinated blocks with long-range ordered morphologies prepared by anionic polymerization
We report a facile synthetic approach to create stable radical block copolymers containing a secondary fluorinated block via anionic polymerization using a bulky, sterically hindered countercation composed of a sodium ion and di-benzo-18-crown-6 complex. The synthetic conditions described in this report allowed for controlled molecular weights and dispersity (<1.3) of both homopolymers: poly(2,2,6,6-tetramethyl-1-piperidinyloxy-methacrylate) (PTMA) and poly(2,2,2-trifluoroethyl methacrylate) (PTFEMA) as well as their block copolymers (PTMA- b -PTFEMA). The stable radical concentration of the polymers was determined by electron spin resonance (ESR) and showed radical content above 70%. An analysis of the microphase morphologies in PTMA- b -PTFEMA thin films via atomic force microscopy (AFM) and grazing incidence small angle X-ray scattering (GISAXS) showed clear evidence of long-range ordering of lamellar and cylindrical morphologies with 32 and 36 nm spacing, respectively. The long-range ordering of the morphologies was developed with the aid of two separate neutral layers: PTMA- ran -PTFEMA- ran -poly(hydroxyl ethyl methacrylate) (PHEMA) and poly(isobutyl methacrylate) (PiBMA)- ran -PTFEMA- ran -PHEMA, which helped us corroborate, along with the Zisman method, the surface energy estimation of PTMA to be 30.1 mJ m −2 .  more » « less
Award ID(s):
1719875
PAR ID:
10146826
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Polymer Chemistry
Volume:
10
Issue:
37
ISSN:
1759-9954
Page Range / eLocation ID:
5094 to 5102
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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