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Abstract The challenge of fabricating transparent and conductive (T/C) films and patterns for applications in flexible electronics, touch screens, solar cells, and smart windows remains largely unsolved. Traditional fabrication techniques are complex, costly, time‐consuming, and struggle to achieve the necessary precision and accuracy over electronic and optical properties. Here, hypersurface photolithography (HP), which integrates microfluidics, a digital micromirror device, and photochemical surface‐initiated polymerizations is used to create polymer brush patterns. The high‐throughput optimization enabled by HP provides conditions to fabricate patterns composed of cross‐linked polymer brushes containing Au‐binding 2‐vinylpyrrolidine (2VP) groups with precise control over the height and the composition at each pixel. Au nanoparticles (AuNPs) are incorporated into the polymer brush patterns through in situ reduction of Au ions, resulting in T/C composite AuNP/polymer brush patterns. The sheet resistance at 100 mA of a 2VP‐AuNP‐functionalized patterns on a glass substrate is 0.42 Ω sq⁻¹with 86% transmittance of visible light. Additional patterns demonstrate multiplexing by copatterning rhodamine B functionalized fluorescent polymer brushes and AuNP/polymer brush conductive domains. This work solves the challenge of creating T/C films by forming metal‐polymer composites from polymer brush patterns, offering a scalable solution for electronic and optical device development and fabrication. 

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. 

Abstract We report a novel glycan array architecture that binds the mannose‐specific glycan binding protein, concanavalin A (ConA), with sub‐femtomolar avidity. A new radical photopolymerization developed specifically for this application combines the grafted‐from thiol–(meth)acrylate polymerization with thiol–ene chemistry to graft glycans to the growing polymer brushes. The propagation of the brushes was studied by carrying out this grafted‐to/grafted‐from radical photopolymerization (GTGFRP) at >400 different conditions using hypersurface photolithography, a printing strategy that substantially accelerates reaction discovery and optimization on surfaces. The effect of brush height and the grafting density of mannosides on the binding of ConA to the brushes was studied systematically, and we found that multivalent and cooperative binding account for the unprecedented sensitivity of the GTGFRP brushes. This study further demonstrates the ease with which new chemistry can be tailored for an application as a result of the advantages of hypersurface photolithography. 

Mechanical activation of reactions can reduce significantly the amounts of solvent and energy required to form covalent organic bonds. 

Controlledradicalpolymerizations(CRPs)areoneofthemost importantways toobtainuniform, definedmolecularweight polymerswith complex composition and architecture such as block copolymers. Anew controlledandlight-initiatedradicalpolymerizationis introducedthatmakes useofthiol initiatorsandanIr-photocatalyst.Differentreactionparametersare studiedfortheirimportanceinthecontrolledcharacteristicsofpolymerization, suchaslowdispersity,controlofmolecularweights,andstraightforwardaccess toblockcopolymers.Thelightcontrolfurthermoreallowsforsimpleswitching onandoffof thepolymerization.Weproposeamechanismfor theso-called thiol-induced, light-activated,controlledradicalpolymerization(TIRP),whichincludestheformationofdormantspeciesandtheir light-andcatalyst-dependentequilibriumwiththeactivepolymerchainend.TIRPenriches theportfolioof controlledandlightinitiatedpolymerizationmethodsby itsviabilityatmildconditions andthepossibility togrowpolymers froma largevarietyof readilyavailablethiols. 

A modified atomic force microscope is used to probe activation effects that may accelerate reactions in a ball mill. 

Hypersurface photolithography (HP) is a printing method for fabricating structures and patterns composed of soft materials bound to solid surfaces and with ∼1 micrometer resolution in the x , y , and z dimensions. This platform leverages benign, low intensity light to perform photochemical surface reactions with spatial and temporal control of irradiation, and, as a result, is particularly useful for patterning delicate organic and biological material. In particular, surface-initiated controlled radical polymerizations can be leveraged to create arbitrary polymer and block-copolymer brush patterns. Here we will review advances in instrumentation architectures that have made these hypersurfaces possible, and the investigations and development of surface-based organic chemistry and grafted-from photopolymerizations that have arisen through these investigations. Over the course of this discussion, we describe specific applications that have benefited from HP. By combining organic chemistry with the instrumentation developed, HP has ushered in a new era of surface chemistry that will lead to new fundamental science and previously unimaginable technologies.