A new method for generating a surface density gradient of polymer chains is presented. A substrate-independent polymer deposition technique was used to coat materials with a chemical gradient based on plasma copolymerization of 1,7-octadiene and allylamine. This provided a uniform chemical gradient to which initiators for atom transfer radical polymerization (ATRP) were immobilized. After surface-initiated atom transfer radical polymerization (SI-ATRP), poly(2-hydroxyethyl methacrylate) (PHEMA) chains were grafted from the surface and the measured thickness profiles provided direct evidence for how surface crowding provides an entropic driving force resulting in chain extension away from the surface. Film thicknesses were found to increase with the position along the gradient surface, reflecting the gradual transition from collapsed to more extended surface-tethered polymer chains as the grafting density increased. The method described is novel in that the approach provides covalent linkages from the polymer coating to the substrate and is not limited to a particular surface chemistry of the starting material.
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Des Monomers Polym
January 2025
Department of Physics Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Sumedang, Indonesia.
Polydimethylsiloxane (PDMS) is a polymer that can be used as a vitreous substitute. To fulfill the need for PDMS on a large scale, synthesis of PDMS in a large number is also needed. Therefore, intensive research is needed to produce PDMS in large quantities.
View Article and Find Full Text PDFDes Monomers Polym
January 2025
Leibniz-Institut für Polymerforschung Dresden e.V, Dresden, Germany.
Enhancing both ionic conductivity and mechanical robustness remains a major challenge in designing solid-state electrolytes for lithium batteries. This work presents a novel approach in designing mechanically robust and highly conductive solid-state electrolytes, which involves ionic liquid-based cross-linked polymer networks incorporating polymeric ionic liquids (PILs). First, linear PILs with different side groups were synthesized for optimizing the structure.
View Article and Find Full Text PDFSoft Matter
January 2025
Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, NO-0315 Oslo, Norway.
Due to the escalating threat of the pathogens' capability of quick adaptation to antibiotics, finding new alternatives is crucial. Although antimicrobial peptides (AMPs) are highly potent and effective, their therapeutic use is limited' as they are prone to enzymatic degradation, are cytotoxic and have low retention. To overcome these challenges, we investigate the complexation of the cationic AMP colistin with diblock copolymers poly(ethylene oxide)--poly(methacrylic acid) (PEO--PMAA) forming colistin-complex coacervate core micelles (colistin-C3Ms).
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Department of Chemical Engineering, Indian Institute of Technology Gandhinagar, India.
Self-assembly of nanoparticles (NPs) in solution has garnered tremendous attention among researchers because of their electrical, chemical, and optoelectronic properties at the macroscale with potential applications in bio-imaging, bio-medicine, and therapeutics. Control of size, shape, and composition at the nanoscale is important in tuning the material's bulk properties. The grafting of NPs with polymers enables us to tune such bulk material properties at the nano level by controlling their assemblies, especially in solutions.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
Department of Applied Science and Technology, Politecnico di Torino, Viale Teresa Michel 5, 15121 Alessandria, Italy.
In polymer science and technology, the distinction between thermoplastic and thermosetting materials has always been sharp, clear, and well-documented: indeed, the former can theoretically be reprocessed a potentially infinite number of times by heating, forming, and subsequent cooling. This cannot be done in the case of thermosetting polymers due to the presence of cross-links that covalently bind the macromolecular chains, giving rise to insoluble and infusible polymeric networks. In 2011, the discovery of vitrimers revolutionized the classification mentioned above, demonstrating the possibility of using new materials that consist of covalent adaptable networks (CANs): this way, they can change their topology through thermally-activated bond-exchange reactions.
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