The dissociation behavior of surface-grafted polyelectrolytes is of interest for the development of stimuli-responsive materials. Metal-chelating polyelectrolyte brushes containing acrylic acid (PAA) or hydroxamic acid (PHA) chelating moieties were grafted from the surface of polypropylene (PP). Fourier transform infrared (FTIR) spectroscopy was used to determine the effective bulk pKa of the polyelectrolyte brushes (pKa(bulk)) and to characterize metal-chelating behavior. The pKa(bulk) values of PP-g-PAA and PP-g-PHA were 6.45 and 9.65, respectively. Both PP-g-PAA and PP-g-PHA exhibited bridging bidentate and chelating bidentate iron chelation complexes. This is the first reported determination of the pK(a,bulk) of surface-grafted poly(hydroxamic) acid.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/am501212g | DOI Listing |
Small
January 2025
Leibniz-Institut für Polymerforschung e. V, Hohe Str. 6, 01069, Dresden, Germany.
Polyelectrolyte brushes (PEBs) undergo conformational transitions due to changes in pH and/or ionic strength, which is leveraged as smart surfaces and on-demand drug-release systems. However, probing conformational transitions of functional PEBs has remained challenging due to low spatiotemporal resolution of characterization methods. Herein, fluorescently-coupled PEBs are devised that give rise to Förster Resonance Energy Transfer (FRET) intrinsically coupled to conformational transitions of chains.
View Article and Find Full Text PDFLangmuir
January 2025
School of Advanced Engineering, Kogakuin University, Tokyo 192-0015, Japan.
Arsenocholine-containing methacrylate (MTAsB) inspired by marine organisms was synthesized by the reaction of 2-bromoethyl methacrylate and trimethylarsine to investigate its polymerization behavior and the fundamental properties of the resulting polymer. Controlled radical polymerization of MTAsB proceeded in the presence of a copper catalyst and imidazolium chloride at 60 °C for 8 h to give a water-soluble polycation with a 94% yield. The smaller amount of nonfreezing water and intermediate water of poly(MTAsB) was observed compared with that of the ammonium-containing polycations.
View Article and Find Full Text PDFJ Colloid Interface Sci
December 2024
School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom. Electronic address:
Understanding the architecture and mechanism of assembly of polyelectrolyte-nucleic acid complexes is critical to the rational design of their performance for gene delivery. Surface-initiated polymer brushes were recently found to be particularly effective at delivering oligonucleotides and maintaining high knock down efficiencies for prolonged periods of time, in highly proliferative cells. However, what distinguishes their binding capacity for oligonucleotides from that of larger therapeutic macromolecules remains unknown.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
Synovial exudation, creeping, and lubrication failure in natural cartilage under a long-term normal loading can be counteracted by a tribo-rehydration (sliding-induced rehydration) phenomenon. Hydrogels, as porous materials, can also restore interfacial lubrication and overcome creep through this strategy. At appropriate sliding velocities, water molecules at the interface contact inlet are driven by hydrodynamic pressures into the porous network to resist creep extrusion.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Research Laboratory "New Polymeric Materials", Nizhny Novgorod State Technical University, n.a. R.E. Alekseev, 24 Minin Street, 603155 Nizhny Novgorod, Nizhegorodskaya Oblast, Russia.
Anionic thermo- and pH-responsive copolymers were synthesized by photoiniferter reversible addition-fragmentation chain transfer polymerization (PI-RAFT). The thermo-responsive properties were provided by oligo(ethylene glycol)-based macromonomer units containing hydrophilic and hydrophobic moieties. The pH-responsive properties were enabled by the addition of 5-20 mol% of strong (2-acrylamido-2-methylpropanesulfonic) and weak (methacrylic) acids.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!