112-69-6Relevant articles and documents
Characterization of Fluorescent Surfactant Aggregates by Fluorimetric and Viscosimetric Techniques
Iwunze,Lambert,Silversmith
, p. 585 - 592 (1997)
A combination of fluorimetric and viscosimetric methods was used to characterize N,N-dimethyl-N-2-(4-(t-butylphenoxy)ethoxy)ethyl-N-hexadecylammonium chloride (BDHC), a double-tailed surfactant with dissimilar tail groups. BDHC was observed to fluoresce at 315 nm when excited at 274 nm, a feature which could be utilized to determine its critical micelle concentration (CMC). A value of 3.98 × 10-5 M was obtained and was observed to be slightly temperature dependent with a Tmin of 25.35°C. Fluorescence quenching experiments using 4-nitroaniline as a quencher were performed in order to determine the aggregation number which was found to be 42.0. The hydrodynamic radius of 21.91 A was obtained using data from viscosimetric experiments. These data, together with the Tanford and Einstein-Stokes relationships, were used to determine the micellar structure (spherical) and the diffusion coefficient (D = 0.97 × 10-6cm2/s), respectively. The ΔG of micellization for BDHC was determined to be -34.9kJ/mol.
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Ingold,Kuriyan
, p. 991 (1933)
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Ru-Catalyzed Selective Catalytic Methylation and Methylenation Reaction Employing Methanol as the C1 Source
Biswas, Nandita,Srimani, Dipankar
, p. 10544 - 10554 (2021/07/31)
Methanol can be employed as a green and sustainable methylating agent to form C-C and C-N bonds via borrowing hydrogen (BH) methodology. Herein we explored the activity of the acridine-derived SNS-Ru pincer for the activation of methanol to apply it as a C1 building block in different reactions. Our catalytic system shows great success toward the β-C(sp3)-methylation reaction of 2-phenylethanols to provide good to excellent yields of the methylated products. We investigated the mechanistic details, kinetic progress, and temperature-dependent product distribution, which revealed the slow and steady generation of in situ formed aldehyde, is the key factor to get the higher yield of the β-methylated product. To establish the environmental benefit of this reaction, green chemistry metrics are calculated. Furthermore, dimerization of 2-naphthol via methylene linkage and formation of N-methylation of amine are also described in this study, which offers a wide range of substrate scope with a good to excellent yield.
End group type macromolecular quaternary ammonium salt and preparation method thereof
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Paragraph 0018, (2019/03/29)
The invention discloses an end group type macromolecular quaternary ammonium salt and a preparation method thereof. Polyhydric alcohols and chlorinated carboxylic acid are dehydrated to produce a macromolecular skeleton in the presence of a catalyst and an appropriate solvent, and the prepared macromolecular skeleton is reacted with tertiary amine so as to obtain the end group type macromolecularquaternary ammonium salt. The macromolecular quaternary ammonium salt is novel in structure and low in toxicity, has strong bacteria inhibiting and resisting effects, and is capable of adjusting the structure according to needs so as to achieve corresponding physical properties. The macromolecular quaternary ammonium salt has wide application prospects in the fields of polymer emulsion, personal care, dry-film preservation, coatings, adhesives, household supplies and the like. The macromolecular quaternary ammonium salt disclosed by the invention is simple and controllable in preparation process, high in operability, mild in conditions, green, environmental-friendly and suitable for industrial production.
Synthesis and properties of biodegradable cationic gemini surfactants with diester and flexible spacers
Xu, Dongqing,Ni, Xiaoyue,Zhang, Congyu,Mao, Jie,Song, Changchun
, p. 542 - 548 (2017/06/06)
A series of cationic gemini surfactants with diester and flexible spacers, namely C12-PG-C12, C14-PG-C14 and C16-PG-C16, were synthesized, purified and characterized. The surface properties and aggregation behavior of the gemini surfactants were investigated by surface tension, electrical conductivity, fluorescence and Krafft point. These gemini surfactants possess higher surface activity than the traditional monomeric surfactants. The thermodynamic parameters exhibited that the micellization was a spontaneous and exothermic process in environment. The micellization process became less favorable with the decrease of alkyl chain length and the increase of temperature. Steady-state fluorescence measurements revealed that the micropolarity and aggregation number of micelles decreased with the increase of hydrocarbon chain length. The Krafft points were taken as ?0?°C, which indicated the synthesized gemini surfactants had good water solubility. The biodegradability of the gemini surfactants were evaluated in river water using Closed Bottle tested and showed their high biodegradation ratio in the open environment due to the diester bond inserting in the flexible spacer of surfactant molecules.
