The structural and dynamic properties of micellar solutions of erucyl bis(hydroxyethyl)methylammonium chloride blended with 2-propanol, in the presence of KCl, have been investigated by means of light scattering and rheological experiments. In the dilute regime, the micellar growth is larger than expected from mean-field or scaling models. The results obtained in the vicinity of the overlap concentration suggest the presence of large aggregates, with size >100 nm, possibly micellar rings or microgels. In the semidilute regime, the relationship between the zero shear viscosity and the surfactant concentration is described by a power law with an exponent in agreement with the mean-field model of linear micelles. The methods based on the analysis of the temperature dependence of the complex shear modulus to provide a measure of the scission energy are discussed.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/la049046m | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Coordinated conformational changes in P450 decarboxylases enable hydrocarbons production from renewable feedstocks.
Nat Commun
January 2025
Brazilian Biorenewables National Laboratory, Brazilian Center for Research in Energy and Materials, Campinas, SP, Brazil.
Fatty acid peroxygenases have emerged as promising biocatalysts for hydrocarbon biosynthesis due to their ability to perform C-C scission, producing olefins - key building blocks for sustainable materials and fuels. These enzymes operate through non-canonical and complex mechanisms that yield a bifurcated chemoselectivity between hydroxylation and decarboxylation. In this study, we elucidate structural features in P450 decarboxylases that enable the catalysis of unsaturated substrates, expanding the mechanistic pathways for decarboxylation reaction.
View Article and Find Full Text PDFMonitoring Polypropylene Chain-Scission for Dissolution-Based Recycling by In Situ Near Infrared and Raman Spectroscopy.
Macromol Rapid Commun
January 2025
CP2M, UMR 5128, CNRS, Universite Claude Bernard Lyon 1, Villeurbanne, 69616, France.
Within the context of polypropylene recycling by dissolution, the potential degradation of polypropylene in solution has been investigated using in situ NIR and Raman spectroscopy. Pure polypropylene, completely free of additives, and commercial polypropylene, low in additives, are degraded on purpose under different conditions. Genetic algorithm combined with partial least squares (GA-PLS) models have been built based on near-infrared (NIR) spectra, and partial least squares (PLS) models based on Raman spectra, to predict the mass average molar mass and the chain-scission rate, respectively, during the degradation process.
View Article and Find Full Text PDFInfluence of ball milling parameters on the mechano-chemical conversion of polyolefins.
RSC Mechanochem
December 2024
Inorganic Chemistry and Catalysis, Institute for Sustainable and Circular Chemistry, Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
Ball-milling of addition polymers such as polyolefins, polystyrene and polyacrylates can be used for depolymerization to obtain the respective monomers. However, absolute yields are typically low, especially from polyolefins which are notoriously difficult to depolymerize. To increase the viability of ball milling as a recycling technique, the effect of milling parameters on small hydrocarbon and monomer yields has to be understood.
View Article and Find Full Text PDFSynthetically Reversible, Proton-Mediated Nitrite N-O Bond Cleavage at a Dicopper Site.
J Am Chem Soc
December 2024
Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States.
A monocationic dicopper(I,I) nitrite complex [Cu(μ-κ:κ-ON)DPFN][NTf] () (DPFN = 2,7-bis(fluoro-di(2-pyridyl)methyl)-1,8-naphthyridine, NTf = N(SOCF)), was synthesized by treatment of a dicopper acetonitrile complex, [Cu(μ-MeCN)DPFN][NTf] (), with tetrabutylammonium nitrite ([BuN][NO]). DFT calculations indicate that is one of three linkage isomers that are close in energy and presumably accessible in solution. Reaction of the μ-κ:κ-ON complex with -TolSH produces nitrous acid (HONO) and the corresponding dicopper thiolate species via an acid-base exchange reaction.
View Article and Find Full Text PDFPolyethylene hydrogenolysis by dilute RuPt alloy to achieve H-pressure-independent low methane selectivity.
Nat Commun
December 2024
State Key Laboratory of Chemical Engineering, Tsinghua University, Beijing, China.
Chemical recycling of plastic waste could reduce its environmental impact and create a more sustainable society. Hydrogenolysis is a viable method for polyolefin valorization but typically requires high hydrogen pressures to minimize methane production. Here, we circumvent this stringent requirement using dilute RuPt alloy to suppress the undesired terminal C-C scission under hydrogen-lean conditions.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!