Photoinduced
metal-free atom transfer radical polymerization (ATRP) activated by
highly conjugated electron-rich thienothiophene derivatives, namely
4-[2-(4-diphenylaminophenyl)-thieno[3,2-b]thiophen-3-yl]benzonitrile
(TT-TPA), 4-[2,5-bis(4-diphenylaminophenyl)-thieno[3,2-b]thiophen-3-yl]benzonitrile (TPA-TT-TPA), 4-(2-(4-(1,2,2-triphenylvinyl)phenyl)
thieno[3,2-b]thiophen-3-yl)benzonitrile (TT-TPE)
and 4-(2,5-bis(4-(1,2,2-triphenylvinyl)phenyl)thieno[3,2-b]thiophen-3- yl)benzonitrile (TPE-TT-TPE) is reported. Polymerization
of methyl methacrylate (MMA) is efficiently activated and deactivated
with light, forming polymers with controlled the molecular weight
characteristics, dispersity, and chain end functionality. Polymerization
studies and DFT calculations revealed that TT-TPA is the most efficient
activator due to the favorable thermodynamic properties.
Many emerging technologies have the potential to improve health care by providing more personalized approaches or early diagnostic methods. In this review, we cover smartphone-based multiplexed sensors as affordable and portable sensing platforms for point-of-care devices. Multiplexing has been gaining attention recently for clinical diagnosis considering certain diseases require analysis of complex biological networks instead of single-marker analysis. Smartphones offer tremendous possibilities for on-site detection analysis due to their portability, high accessibility, fast sample processing, and robust imaging capabilities. Straightforward digital analysis and convenient user interfaces support networked health care systems and individualized health monitoring. Detailed biomarker profiling provides fast and accurate analysis for disease diagnosis for limited sample volume collection. Here, multiplexed smartphone-based assays with optical and electrochemical components are covered. Possible wireless or wired communication actuators and portable and wearable sensing integration for various sensing applications are discussed. The crucial features and the weaknesses of these devices are critically evaluated.
In this work, a new strategy for the synthesis of self-healable/recyable polybenzoxazine networks under mild conditions, by exploiting dynamic B–O bond exchanges is presented. The process is based on mixing...
A coumarinacyl
anilinium (CAA) salt, facilely synthesized
via a one-pot reaction, is shown to be a versatile visible and NIR
photoinitiator for cationic and step-growth polymerizations. CAA salt exhibits superior photoinitiation performance as
compared to commercial iodonium salt in cationic polymerization. Upon
visible-light irradiation, this salt undergoes hemolytic and heterolytic
cleavage and subsequent electron transfer and hydrogen abstraction
reactions, forming reactive species capable of initiating cationic
polymerization of epoxides and vinyl monomers. After a short irradiation
period, polymerization also proceeds in the dark due to the non-nucleophilic
nature of the counteranion. NIR-induced polymerizations were successfully
conducted based on upconversion photochemistry. CAA salt
can also initiate step-growth polymerization of N-ethyl carbazole (NEC) by oxidation of the monomer by the photochemically
formed anilium radical cations. Subsequent proton release and radical
coupling reactions essentially yield polycarbazole. CAA salt, featuring straightforward synthesis and long-wavelength sensitivity
as well as versatile photoinitiating performance, has great potential
in various applications.
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