The surface-initiated ATRP of benzyl methacrylate, methyl methacrylate, and styrene from magnetite nanoparticle is investigated, without the use of sacrificial (free) initiator in solution. It is observed that the grafting density obtained is related to the polymerization kinetics, being higher for faster polymerizing monomer. The grafting density was found to be nearly 2 chains/nm2for the rapidly polymerizing benzyl methacrylate. In contrast, for the less rapidly polymerizing styrene, the grafting density was found to be nearly 0.7 chain/nm2. It is hypothesized that this could be due to the relative rates of surface-initiated polymerization versus conformational mobility of polymer chains anchored by one end to the surface. An amphiphilic diblock polymer based on 2-hydroxylethyl methacrylate is synthesized from the polystyrene monolayer. The homopolymer and block copolymer grafted MNs form stable dispersions in various solvents. In order to evaluate molecular weight of the polymer that was grafted on to the surface of the nanoparticles, it was degrafted suitably and subjected to gel permeation chromatography analysis. Thermogravimetric analysis, transmission electron microscopy, and Fourier transform infrared spectroscopy were used to confirm the grafting reaction.
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http://dx.doi.org/10.1007/s11671-009-9365-z | DOI Listing |
Water Res
January 2025
China Electronics System Engineering No.2 Construction Co., Ltd., Wuxi 214115, PR China.
Copper-containing industrial wastewater, characterized by strong acidity, high ionic strength, and various competing metals, presents significant challenges for Cu(II) recovery. To address these issues, an electric field-enhanced ultrafiltration process was developed, assisted with a functional polyelectrolyte with high selectivity for Cu(II). The polyelectrolyte, termed PPEI, was synthesized by grafting picolyl groups onto polyethyleneimine (PEI), enhancing its affinity for Cu(II).
View Article and Find Full Text PDFJ Fr Ophtalmol
January 2025
Service d'ophtalmologie, hôpital La Timone, 264, rue Saint-Pierre, 13005 Marseille, France.
Purpose: To analyze the outcomes and frequency of complications after Descemet's membrane endothelial keratoplasty (DMEK) and evaluate the parameters associated with the occurrence of these complications.
Methods: A multicenter retrospective study of 143 DMEK procedures performed consecutively by five surgeons between June 2018 and March 2021 was performed. Surgeon-specific surgical and graft characteristics were also assessed.
Int J Mol Sci
December 2024
Petrovsky National Research Centre of Surgery, Abrikosovsky per. 2, 119991 Moscow, Russia.
Bilio-biliary anastomosis (BBA) is a critical surgical procedure that is performed with the objective of restoring bile duct continuity. This procedure is often required in cases where there has been an injury to the extrahepatic bile ducts or during liver transplantation. Despite advances in surgical techniques, the healing of BBA remains a significant challenge, with complications such as stricture formation and leakage affecting patient outcomes.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Department of Advanced Prosthodontics, Graduate School of Medical and Dental Sciences, Institute of Science Tokyo, Yushima, Tokyo 1138549, Japan.
β-tricalcium phosphate (β-TCP) is a widely utilized resorbable bone graft material, whose surface charge can be modified by electrical polarization. However, the specific effects of such a charge modification on osteoblast and osteoclast functions remain insufficiently studied. In this work, electrically polarized β-TCP with a high surface charge density was synthesized and evaluated in vitro in terms of its physicochemical properties and biological activity.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Shaanxi Collaborative Innovation Center of Industrial Auxiliary Chemistry and Technology, Shaanxi University of Science and Technology, Xi'an 710021, China.
This study introduces a novel water-insoluble dispersant for coal water slurry (CWS), namely, a poly(sodium styrene sulfonate)- SiO nanoparticle (SiO--PSSNa). SiO--PSSNa was synthesized by combining the surface acylation reaction with surface-initiated atom transfer radical polymerization (SI-ATRP). Fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectroscopy (XPS), energy dispersive spectrometer (EDS), nuclear magnetic resonance spectroscopy (NMR) and thermogravimetric analysis (TGA) verified that SiO--PSSNa with the desired structure was successfully obtained.
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