Contamination of underground water by uranium (U) and other heavy metals is a growing concern. Mesoporous silica nanoparticles (MSNs) have shown great potential as an adsorbent material for heavy metal removal. This study synthesized a novel MSN using surface-initiated atom transfer radical polymerization (SI-ATRP) and evaluated its effectiveness for removing uranium from aqueous solutions under different conditions.
View Article and Find Full Text PDFThree new hybrid metal-polymer-coordinated complexes (MPCs) of copper(II), cobalt(II), and nickel(II) ions with an organic polymer derived from gallic acid and ethylenediamine (GAEtH) were synthesized. The structures of GAEtH and MPCs were characterized with FT-IR, ultraviolet (UV)-Vis, H and C NMR spectroscopy, and elemental and thermogravimetric analysis. The results reveal that the organic polymer GAEtH exhibits an infinite one-dimensional chain structure, while the hybrid MPCs have a double chain structure, with the two chains joined by metal ions.
View Article and Find Full Text PDFOur goal is to develop a structural ceramic for high-temperature applications in which silicon carbide-based materials (SiCs) are used as matrix composites. The potential of SiCs to deposit a mixture of SiC and zirconium diboride (ZrB) plasma spray coating is analyzed. To deposit thermal barrier layers containing up to 50 vol.
View Article and Find Full Text PDFTwo novel low band gap donor-acceptor (D-A) copolymers, poly[9,10-bis(4-(dodecyloxy)phenyl)-2,6-anthracene-alt-5,5-(4',7'-bis(2-thienyl)-2',1',3'-benzothiadiazole--5,6-(3,7-dimethyloctyl)dicarboxylic imide)] (PPADTBTDI-DMO) and poly[9,10-bis(4-(dodecyloxy)phenyl)-2,6-anthracene-alt-5,5-(4',7'-bis(2-thienyl)-2',1',3'-benzothiadiazole-5,6--octyl-dicarboxylic imide)] (PPADTBTDI-8) were synthesized in the present work by copolymerising the bis-boronate ester of 9,10-phenylsubstituted anthracene flanked by thienyl groups as electron-donor units with benzothiadiazole dicarboxylic imide (BTDI) as electron-acceptor units. Both polymers were synthesized in good yields via Suzuki polymerisation. Two different solubilizing alkyl chains were anchored to the BTDI units in order to investigate the impact upon their solubilities, molecular weights, optical and electrochemical properties, structural properties and thermal stability of the resulting polymers.
View Article and Find Full Text PDFCurrently, chemotherapy is an important method for the treatment of various cancers. Nevertheless, it has many limitations, such as poor tumour selectivity and multi-drug resistance. It is necessary to improve this treatment method by incorporating a targeted drug delivery system aimed to reduce side effects and drug resistance.
View Article and Find Full Text PDFThis work presents the synthesis of pH-responsive poly(2-(diethylamino) ethyl methacrylate) (PDEAEMA) brushes anchored on hollow mesoporous silica nanoparticles (HMSN-PDEAEMA) via a surface-initiated ARGET ATRP technique. The average size of HMSNs was ca. 340 nm, with a 90 nm mesoporous silica shell.
View Article and Find Full Text PDFBecause of the increased demand for preceramic polymers in high-tech applications, there has been growing interest in the synthesis of preceramic polymers, including polysiloxanes and alumina. These polymers are preferred because of their low thermal expansion, conformability to surfaces over large areas, and flexibility. The primary objective was to evaluate the aspects of polymer-derived ceramic routs, focusing on the UV lithography process of preceramic polymers and the pyrolyzing properties of the final ceramics.
View Article and Find Full Text PDFMolecules
January 2020
This paper introduces the synthesis of well-defined 2-(tert-butylamino)ethyl methacrylate-b-poly(ethylene glycol) methyl ether methacrylate diblock copolymer, which has been grafted onto mesoporous silica nanoparticles (PTBAEMA-b-PEGMEMA-MSNs) via atom transfer radical polymerization (ATRP). The ATRP initiators were first attached to the MSN surfaces, followed by the ATRP of 2-(tert-butylamino)ethyl methacrylate (PTBAEMA). CuBr2/bipy and ascorbic acid were employed as the catalyst and reducing agent, respectively, to grow a second polymer, poly(ethylene glycol) methyl ether methacrylate (PEGMEMA).
View Article and Find Full Text PDFPoly(2‑(tert-butylamino)ethyl methacrylate) brushes (PTBAEMA) are grown from mesoporous silica nanoparticles via surface-initiated atom transfer radical polymerization (SI-ATRP). Linear PTBAEMA brushes are protonated and highly swollen at low pH; brushes are collapsed at pH higher than 7.7 due to deprotonation, as determined by dynamic light scattering (DLS).
View Article and Find Full Text PDFThe preparation of anthracene-based low band gap conjugated polymers comprising 2,6-linked anthracene and dithienyl-benzo[c][1,2,5]thiadiazole or dibithiophenyl-benzo[c][1,2,5]thiadiazole alternate repeat units is presented. The photophysical, electrochemical and photovoltaic properties of the polymers in bulk heterojunction solar cells using PC(71)BM as an acceptor are discussed.
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