We report novel supramolecular polymers, which possess a reversed viscosity/temperature profile. To this end, we developed a series of ditopic monomers featuring two self-complementary binding sites, either the guanidiniocarbonyl pyrrole carboxylic acid (GCP) or the aminopyridine carbonyl pyrrole carboxylic acid (ACP). At low temperatures, small cyclic structures are formed. However, at elevated temperatures, a ring-chain transformation leads to the formation of a supramolecular polymer. We demonstrate that this effect is dependent on the concentration of the solution and on the polarity of the solvent. This effect can counteract the loss of viscosity of the solvent at elevated temperatures, thus opening an application of our systems as viscosity index improvers (VIIs) in working fluids. This was tested for different motor oils and led to the identification of one compound as a promising VII.
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http://dx.doi.org/10.3762/bjoc.17.11 | DOI Listing |
Nanomaterials (Basel)
December 2024
Department of Chemistry, University of Sherbrooke, 2500, Blvd de l'Université, Sherbrooke, QC J1K 2R1, Canada.
This study delves into the distinctive selective property exhibited by a non-conjugated cholesterol-based polymer, poly(CEM--EHA), in sorting semiconducting single-walled carbon nanotubes (s-SWCNTs) within isooctane. Comprised of 11 repeating units of cholesteryloxycarbonyl-2-hydroxy methacrylate (CEM) and 7 repeating units of 2-ethylhexyl acrylate (EHA), this non-conjugated polymer demonstrates robust supramolecular interactions across the sp surface structure of carbon nanotubes and graphene. When coupled with the Double Liquid-Phase Extraction (DLPE) technology, the polymer effectively segregates s-SWCNTs into the isooctane phase (nonpolar) while excluding metallic SWCNTs (m-SWCNTs) in the water phase (polar).
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Sree Chitra Tirunal Institute for Medical Sciences and Technology, Bioceramics Division, Biomedical Technology Wing, 695011, Thiruvananthapuram, INDIA.
A collagen-inspired helical protein-mimic has been synthesized via topochemical polymerization of a designed tripeptide monomer. In the monomer crystal, molecules arrange in a head-to-tail manner, forming supramolecular helices. The azide and alkyne of adjacent molecules in the supramolecular helix are proximally preorganized in a ready-to-react arrangement.
View Article and Find Full Text PDFSmall
January 2025
Department of Polymers & Functional Materials, CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad, Telangana, 500007, India.
Heterostructures comprise two or more different semiconducting materials stacked either as co-assemblies or self-sorted based on their dynamics of aggregates. However, self-sorting in heterostructures is rather significant in improving the short exciton diffusion length and charge separation. Despite small organic molecules being known for their self-sorting nature, macrocyclic are hitherto unknown owing to unrestrained assemblies from extended π-conjugated systems.
View Article and Find Full Text PDFACS Mater Lett
January 2025
Department of Chemistry, Durham University, Durham, DH1 3LE, U.K.
The study of structure-activity relationships is a top priority in the development of nontraditional luminescent materials. In this work, nonconjugated polyurethanes (PUs) with full-color emission (red, green, and blue) are easily obtained by control of the diol monomer structure and the polymerization conditions. Selected diol monomers introduced single, double, or triple bond repeating units into the main chain of the PUs, in order to understand how unsaturated bonds and H-bonds affect their luminescence from a molecular orbital viewpoint.
View Article and Find Full Text PDFACS Nano
January 2025
Bio-Organic Chemistry, Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
The morphology of nanodrugs is of utmost importance in photothermal therapy because it directly influences their physicochemical behavior and biological responses. However, clarifying the inherent relationship between morphology and the resultant properties remains challenging, mainly due to the limitations in the flexible morphological regulation of nanodrugs. Herein, we created a range of morphologically controlled nanoassemblies based on poly(ethylene glycol)--poly(d,l-lactide) (PEG-PLA) block copolymer building blocks, in which the model photosensitizer phthalocyanine was incorporated.
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