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Title: Orthogonal Images Concealed Within a Responsive 6‐Dimensional Hypersurface
Abstract

A photochemical printer, equipped with a digital micromirror device (DMD), leads to the rapid elucidation of the kinetics of the surface‐initiated atom‐transfer radical photopolymerization ofN,N‐dimethylacrylamide (DMA) andN‐isopropylacrylamide (NIPAM) monomers. This effort reveals conditions where polymer brushes of identical heights can be grown from each monomer. With these data, hidden images are created that appear upon heating the substrate above the lower critical solution temperature (LCST) of polyNIPAM. By introducing a third monomer, methacryloxyethyl thiocarbamoyl rhodamine B, a second, orthogonal image appears upon UV‐irradiation. With these studies, it is shown how a new photochemical printer accelerates discovery, creates arbitrary patterns, and addresses long‐standing problems in brush polymer and surface chemistry. With this technology in hand a new method is demonstrated to encrypt data within hypersurfaces.

 
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Award ID(s):
2032176
PAR ID:
10449332
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials
Volume:
33
Issue:
21
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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