Facile and efficient Cu(0)-mediated radical polymerisation of pentafluorophenyl methacrylate grafting from poly(ethylene terephthalate) film

A microgel of CdSe quantum dots for fluorescent bisphenol A detection

A fluorescent microgel for BPA detection has been successfully prepared by cross-linking linear poly(styrene-co-glycidyl methacrylate) (poly (STY-co-GMA)) with L-cysteine-capped CdSe quantum dots (Lcys-caped CdSe QDs). The microgel contained specific binding sites created by the covalent grafting of the copolymer onto the QDs via the GMA units, allowing for selective trapping of BPA molecules through π-π and hydrogen bond interactions with phenyl, carboxylic, and amine groups. After binding, electron transfer from the QDs to the analyte quenched the fluorescence at a wavelength of 547 nm when excited at 400 nm. The rational compositional and structural design allows the microgel to accurately detect BPA concentrations over a wide dynamic range of 1.0×10^-1 to 1.0×10⁵ μg/L with a low detection limit (7.0×10^-2 to 8.0×10^-2 μg/L) in deionized, drinking, and tap waters within just 2.0 min. On top of that, the sensitivity for BPA detection was 2.0-4.6 times higher than that of the other 3 structural analogues, even molecular imprinting was not involved. The influence of the STY/GMA compositions in the copolymers and environmental conditions, including pH and ionic strength, on the sensing performance was determined. Moreover, the sensing mechanism and the selectivity with respect to the molecular features were elucidated.

Copolymers Derived from Two Active Esters: Synthesis, Characterization, Thermal Properties, and Reactivity in Post-Modification

Copolymers with two distinguished reactive repeating units are of great interest, as such copolymers might open the possibility of obtaining selective and/or consequent copolymers with different chemical structures and properties. In the present work, copolymers based on two active esters (pentafluorophenyl methacrylate and p-nitrophenyl methacrylate) with varied compositions were synthesized by Cu(0)-mediated reversible deactivation radical polymerization. This polymerization technique allows the preparation of copolymers with high to quantitative conversion of both comonomers, with moderate control over dispersity (Đ = 1.3–1.7). Additionally, by in-depth study on the composition of each copolymer by various techniques including elemental analysis, NMR, FT-IR, and XPS, it was possible to confirm the coherence between expected and obtained composition. Thermal analyses by DSC and TGA were implemented to investigate the relation between copolymers’ composition and their thermal properties. Finally, an evaluation of the difference in reactivity of the two monomer moieties was confirmed by post-modification of copolymers with a primary amine and a primary alcohol as the model.

Incorporation of silver stearate nanoparticles in methacrylate polymeric monoliths for hemeprotein isolation

A unique method was used to synthesize extremely stable silver stearate nanoparticles (AgStNPs) incorporated in an organic-based monolith. The facile strategy was then used to selectively isolate hemeproteins, myoglobin (Myo) and hemoglobin (Hb). Ethyl alcohol, silver nitrate, and stearic acid were, respectively, utilized as reducing agents, silver precursors, and capping agents. The color changed to cloudy from transparent, indicating that AgStNPs had been formed. AgStNP nanostructures were then distinctly integrated into the natural polymeric scaffold. To characterize the AgStNP–methacrylate polymeric monolith and the silver nanoparticles, energy-dispersive X-ray (EDX), scanning electron microscopy (SEM), and Fourier-transform infrared (FT-IR) spectroscopy were used. The results of the SEM analysis indicated that the AgStNP–methacrylate polymeric monolith’s texture was so rough in comparison with that of the methacrylate polymeric monolith, indicating that the extraction process of the monolith materials would be more efficient because of the extended surface area of the absorbent. The comparison between the FT-IR spectra of AgStNPs, the bare organic monolith, and AgStNP–methacrylate polymeric monolith confirms that the AgStNPs were immobilized on the surface of the organic monolith. The EDX profile of the built materials indicated an advanced peak of the Ag sequence which represented an Ag atom of 3.27%. The results therefore established that the AgStNPs had been successfully integrated into the monolithic materials. Extraction efficiencies of 92% and 97% were used to, respectively, recover preconcentrated Myo and Hb. An uncomplicated method is a unique approach of both fabrication and utilization of the nanosorbent to selectively isolate hemeproteins. The process can further be implemented by using other noble metals.

Preparation of ZnO quantum dots@SiO2/PVA for multifunctional coating on PET

A durable, highly transparent and ultraviolet shielded inkjet printing coating was successfully prepared using ZnO QDs@SiO₂.