A5056307002- Photopolymerization techniques and applications
- Esophageal and GI Pathology
- Analytical Chemistry and Sensors
- Pancreatic and Hepatic Oncology Research
- Advanced Polymer Synthesis and Characterization
- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- Gastrointestinal disorders and treatments
- Luminescence and Fluorescent Materials
- Click Chemistry and Applications
- Polymer composites and self-healing
- Synthetic Organic Chemistry Methods
- Advanced biosensing and bioanalysis techniques
- Colorectal Cancer Screening and Detection
- Molecular Sensors and Ion Detection
- Synthesis and properties of polymers
- Pediatric Hepatobiliary Diseases and Treatments
- Carbon dioxide utilization in catalysis
- Molecular Junctions and Nanostructures
- RNA Interference and Gene Delivery
- Dental materials and restorations
- Silicone and Siloxane Chemistry
- Organic Light-Emitting Diodes Research
- Esophageal Cancer Research and Treatment
- Gallbladder and Bile Duct Disorders
University of Colorado Boulder
2018-2024
Northwestern University
2023-2024
University of Colorado System
2018-2021
Johns Hopkins University
2012-2014
Indian Institute of Technology Bombay
2007-2011
Indian Institute of Technology Guwahati
2009
Sweet Briar College
2008
Virginia Tech
2008
Pennsylvania State University
2001-2003
Rubber Board
2001
Abstract The reaction of thiols and anhydrides to form ring opened thioester/acids is shown be highly reversible it accordingly employed in the fabrication covalent adaptable networks (CANs) that possess tunable dynamic chemistry. Maleic, succinic, phthalic anhydride derivatives were used as bifunctional reactants systems with varied stoichiometries, catalyst, loadings. Dynamic characteristics such temperature‐dependent stress relaxation, direct reprocessing recycling abilities a range...
Abstract Significant progress has been made in designing organic semiconducting materials (OSCs) for the past few decades field‐effect transistors (OFETs). Much attention paid to development of p‐channel OSCs, with less but highly significant on n‐channel OSCs. In this review, we focus advances OFETs last years achieve high performance modes, air stability, and solution processability, leading printable active electronics. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Phys,
We describe a sensitive, large-area thin film transistor (TFT) sensor platform for real time detection of low-concentration protein analytes in solution. The sensing area is 7 mm by mm. p-channel (pentacene) and n-channel (a naphthalenetetracarboxylic diimide, NTCDI) organic molecules were each used as semiconductors conjunction with newly designed receptor–antibody-functionalized top dielectric layer. This layer, incorporating both fluorinated polymer vapor-deposited hydrocarbon, provided...
A scalable synthesis of high refractive index, optically transparent photopolymers from a family low-viscosity multifunctional thiol and alkyne monomers via thiol–yne "click" is described herein. The designed to incorporate index cores consisting aryl sulfide groups with intrinsic molar refraction were synthesized starting commercially available low-cost raw materials. (<500 cP) resins formulated these new phosphine oxide photoinitiator underwent efficient polymerizations upon exposure 405...
Abstract Hydrogels are often synthesized through photoinitiated step‐, chain‐, and mixed‐mode polymerizations, generating diverse network topologies resultant material properties that depend on the underlying connectivity. While many photocrosslinking reactions available, few afford controllable connectivity of hydrogel network. Herein, a versatile photochemical strategy is introduced for tuning structure poly(ethylene glycol) (PEG) hydrogels using macromolecular monomers functionalized with...
Abstract Naphthalenetetracarboxylic diimide derivatives (octyl “8” NTCDI, dimethylaminopropyl “DMP” NTCDI) and copper phthalocyanine (CuPc) are used to form a diverse organic field‐effect transistor (OFET) sensor array. CuPc 8‐NTCDI p‐channel n‐channel semiconductors, respectively, showing expected opposing responses analytes. DMP‐NTCDI, on the other hand, because of its ionizable side chain, shows response directions magnitudes that not correlated those two. The result is distinct pattern...
Kinetic parameters and their influence on the overall rates of base-catalyzed thiol–Michael reactions proceeding via an alternating propagation chain transfer cycle were evaluated. A kinetic model was developed that enables determination accurate prediction reaction paths for addition its accompanying polymerization. Individual steps evaluated three commonly used thiol vinyl functional monomers. Chain determined in binary combinations monomers from analysis experimental data rates....
A high-performance holographic recording medium was developed based on a unique combination of photoinitiated thiol-ene click chemistry and functional, linear polymers used as binders. Allyl reactive sites were incorporated along the backbone polymer binder to enable facile film casting facilitate cross-linking by photopolymerization monomers that also serve writing in this distinctive approach materials. The allyl content ratio varied maximize control refractive index contrast....
"Click"able monomer and polymers based on 3,4-propylenedioxythiophene, ProDOT, which can be functionalized either at the stage or after polymerization, were synthesized characterized for first time. The solubility of these fine-tuned from organic to aqueous solvents by functionalization with an appropriate side chain. In fact, "click"able functionality allows us synthesize chatacterize water-soluble ProDOT-based cationic polymer hitherto unknown. Chemical polymerization...
The effects of surface roughness, oxidation level, and liquid subcooling on the minimum film boiling temperature, T min, during quenching a nuclear fuel rod were investigated experimentally. An instrumented simulator (FRS) was designed fabricated with different combinations cladding (Inconel Zircaloy) filler (BN Al2O3) materials. Surface roughness varied by polishing FRS grades emery cloth, whereas level heating in an oven under carefully controlled conditions for time periods. eddy-current...
Water-soluble sulfonated monomer based on 3,4-propylenedioxythiophene (ProDOT-sultone) was synthesized and characterized for the first time via O-alkylation of corresponding unreactive β,β-disubstituted hydroxyl group with propane sultone in presence a catalytic amount 1,4-diazabicyclo[2.2.2]octane (DABCO). This new oxidatively polymerized to produce regioregular water-soluble conjugated anionic polyelectrolyte, which then used fabrication solid-state electrochromic devices using...
Organic field effect transistors based on poly(3-hexylthiophene) and CuII tetraphenylporphyrin composite were investigated as sensors for detection of vapors nitrobased explosive compounds, viz., 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX), 2,4,6-trinitrotoluene (TNT), dinitrobenzene, which are also strong oxidizing agents. Significant changes, suitable sensor response, observed in transistor “on” current (Ion) conductance (S) after exposure. A similar device response was, however, not...
Dynamic covalent chemistry was employed to improve the holographic grating performance by facilitating diffusion of monomers and network rearrangement in a photopolymer system. Because high degree spatiotemporal control afforded radical-mediated addition–fragmentation chain transfer reaction between allyl sulfide (AS) moieties thiols, this proved well-suited for formation high-quality photopolymers. Through exchange with monofunctional thiol, polymer chains incorporating AS along backbone...
Click chemistry has been successfully applied in the synthesis of first example a triazole-bridged porphyrin dyad containing N(2)S(2) and N(4) or ZnN(4) subunits, fluorescence study indicated possibility singlet-singlet energy transfer from subunit to N(20S(2) subunit.
Step-growth thiol-Michael photopolymerizable resins, constituting an alternative chemistry to the current methacrylate-based chain-growth polymerizations, were developed and evaluated for use as dental restorative materials. The beneficial features inherent anion-mediated polymerizations explored, such rapid photocuring, low stress generation, ester content tunability, improved mechanical performance in a moist environment. An ester-free tetrafunctional thiol ultraviolet-sensitive photobase...
Amine–peroxide redox polymerization (APRP) has been highly prevalent in industrial and medical applications since the 1950s, yet initiation mechanism of this radical process is poorly understood so that innovations field are largely empirically driven incremental. Through a combination computational prediction experimental analysis, we elucidate important reaction between amines benzoyl peroxide for ambient production initiating radicals. Our calculations show APRP proceeds through SN2...
Abstract Background and study aims Adherence to quality indicators (QIs) best practices (BPs) for endoscopic surveillance of Barrett’s esophagus (BE) is low based on clinical documentation which an inaccurate representation events occurring during procedures. This aimed assess adherence measurable QI BP using video evaluation. Methods We performed a single center video-based retrospective review endoscopies BE ≥1 cm between March 1, 2018 October 2020. QIs BPs was assessed through...
In the present work, photocatalytic activity was investigated toward a thiol-Michael reaction of different combinations 9-fluorenylmethyl carbamate (Fmoc) derivatives and photocaged amines (PCA) as base amplifiers catalytic base, respectively. This phototriggering approach systematically studied for evaluating its effect on kinetics between thiol Michael acceptors like acrylate or sulfone wherein, butyl 3-mercaptopropionate (BMP), 1-hexyl (HA), ethyl vinyl (EVS) were used model reactants....
We report a synthesis route to thiophene polymer where the repeat unit consists of 3,3‴-didodecylquaterthiophene (as in PQT12) plus an additional ring from which other functional groups may be projected. The hydroxymethyl form this polymer, while only poor semiconductor its own right, serves as vehicle for compatibilizing PQT12 itself with arbitrary groups. In article, we focus on tetrathiafulvalene (TTF) functionality. As expected, TTF group acts hole trap, shown by loss mobility and...
Abstract The reaction of thiols and anhydrides to form ring opened thioester/acids is shown be highly reversible it accordingly employed in the fabrication covalent adaptable networks (CANs) that possess tunable dynamic chemistry. Maleic, succinic, phthalic anhydride derivatives were used as bifunctional reactants systems with varied stoichiometries, catalyst, loadings. Dynamic characteristics such temperature‐dependent stress relaxation, direct reprocessing recycling abilities a range...
Radical photopolymerization (RPP) has grown into a multibillion-dollar technology for reduced energy consumption and waste with increased productivity. However, radical-mediated polymerization ceases almost immediately following discontinuation of irradiation because rapid termination reactive centers. This restricts the wider use RPP in applications that involve light attenuation or irregular surfaces uniform is not guaranteed these challenging exposure conditions resultant undercuring...
A systematic investigation extends the fundamental understanding of structure–property relationships between vinyl functionality and reaction kinetics for thiol-Michael reactions.