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Fabrication and Functionalization of Other Inorganic Nanoparticles and Nanocomposites
Published in Vineet Kumar, Praveen Guleria, Nandita Dasgupta, Shivendu Ranjan, Functionalized Nanomaterials I, 2020
Kiranmai Mandava, Uma Rajeswari B.
Another approach to incorporate TONPs into the polyamide matrix using oleic acid in heptanes as a surface modifier is via biphasic solvothermal reaction. A trimesoyl chloride-heptane solution is added to titania suspension in heptanes to fabricate a thin film nanocomposite (TFN) polyamide (PA) membrane (Khorshidi et al., 2018). The membranes used in desalination equipment have been prepared by super hydrophilic TFN membranes. Due to the poor chemical stability of conventional polyamide membranes, different membranes prepared with carboxylated titania and hydroxylated titania are being used as a nanofiller to improve the performance of the resultant TFN membranes in view of vapor permeance and selectivity (Arthanareeswaran and Thanikaivelan, 2010; Hamid et al., 2011; Zhao et al., 2012). A new thermally stable and optically active poly(ester-imide) was synthesized via direct polyesterification of N,N'-(pyromellitoyl)-bis-(L-tyrosinedimethylester) and N-trimellitylimido-L-methionine using tosyl chloride/pyridine/N,N'-dimethylformamide system as a condensing agent. After PEI/titanium bionanocomposites were prepared using the modified nanosized TiO2 via sonochemical reaction, which can accelerate hydrolysis and improve the dispersion of the nanoparticles in the polymer matrix (Mallakpour et al., 2011).
Chapter 4: Monodisperse Polymer Particles in Immunoassays and Cell Separation
Published in Alan Rembaum, Zoltán A. Tökés, Micro spheres: Medical and Biological Applications, 2017
Kjell Nustad, Havard Danielsen, Albrecht Reith, Steinar Funderud, Tor Lea, Frode Vartdal, John Ugelstad
Minor modifications in the attachment of antibodies are introduced to obtain sterile preparations. Particles are suspended in sterile pyrogen-free water at a concentration of 10 to 100 mg/mℓ and sonicated for 3 min in a water bath to obtain a single-particle suspension. The particles are then sterilized by treatment in 70% ethanol for 1 hr or autoclaved at 120°C for 20 min. Tosylation is performed on autoclaved particles since this procedure increases the number of hydroxyl groups available for activation. The entire procedure is performed in the bottle used for autoclaving. The tosylation procedure is similar to that used for nonmagnetic particles with 4 g tosyl chloride and 4 mℓ pyridine per gram particles.8 A treatment with 70% ethanol is included after tosylation as an extra sterilization step.
The Synthesis and Properties of New Oxygen- and Nitrogen- Containing Terpene Acid Derivatives
Published in Alexander V. Kutchin, Lyudmila N. Shishkina, Larissa I. Weisfeld, Gennady E. Zaikov, Ilya N. Kurochkin, Alexander N. Goloshchapov, Chemistry and Technology of Plant Substances, 2017
Maksim P Bei, Anatolij P Yuvchenko
Treatment of amido diacid 15h with diethyl sulfate in DMF in the presence of potassium carbonate afforded diethyl ester 17 in 99% yield, it was converted into diol 18 by reduction with LiAlH4 in 58% yield. One of the most effective methods of alcohol transformation into halide is a preparation of sulfonates (in particular, tosylates) and subsequent nucleophilic substitution of p-toluenesulfonyl group by halide ion. For the synthesis of ditosylate 19 from diol 18, we used two well-known methods: reactions of alcohol with tosyl chloride in pyridine or in methylene chloride in the presence of organic base and catalytic amounts of DMAP [33]. The use of the first method did not give a satisfactory result: Isolated ditosylate 19 contains large amounts of impurities, and only the second method gave the target ditosylate 19 almost in quantitative yield (98%) (Fig. 3.11).
Thiourea-based low molecular-mass organogelators from (+)-dehydroabietylamine
Published in Journal of Sulfur Chemistry, 2023
Afsheen Afsar, Muhammad Naveed Javed, Imran Ali Hashmi, Shoaib Muhammad, Ahmed Bari, Firdous Imran Ali
Commercially available isomeric mixture (60%) of DAA was purified using toluene-acetic acid to obtain DAA-acetate as crystalline salt (vide experimental, supplementary information). The synthesis of gelators commenced with the treatment of purified (+)-DAA with carbon disulfide in the presence of triethylamine and THF at room temperature followed by reaction with tosyl chloride to obtain isothiocyanate (2) in good yield as colourless highly viscous oil [26]. The isothiocyanate (2) is then separated through column chromatography using hexane as eluent. To understand the role of spacer length on gelation, aliphatic n-alkyl chains of different length (hexyl, octyl, dodecyl) and (+)-DAA installed on linker, i.e. thiourea moiety. Thioureas 3-5 were obtained as white solids in moderate to excellent yields, on reaction of 2 with commercially available primary alkylamines in ethanol at 0°C for overnight (Scheme 1). Thiourea 5 was obtained as milky white solid by mixing 2 with pure DAA in absolute ethanol and leaving overnight in refrigerator. The structures of compounds were determined by 1H and 13C NMR spectra (vide supporting information). Thiourea 6 is already reported compound and its structure confirmed through comparison with the reported spectroscopic data [27].
New chiral liquid crystal cyclic monomers based on diosgenin: synthesis and mesomorphism
Published in Liquid Crystals, 2018
Zhihao Guo, Pan Li, Xiaofeng Liu, Liqun Yang, Jianshe Hu, Zhangpei Chen
Tosyl chloride, 1,4-butanediol, palladium 10% on carbon and benzyl chloride were purchased from Sinopharm Chemical Reagent Co., Ltd. (Shenyang, China). Diosgenin was purchased from Wuhan Chemical Industry Co., Ltd. (Wuhan, China). 1,2-Ethanediol was purchased from Tianjin Bodi Chemical Industry Co., Ltd. (Tianjin, China). 1,6-Hexanediol and 1,8-octanediol were purchased from Qingdao Lilai Fine Chemical Industry Co., Ltd. (Qingdao, China). 2,2-Bis(hydroxymethyl)propionic acid was purchased from Nanjing Weiao Chemical Industry Co., Ltd. (Nanjing, China). Ethyl chloroformate was purchased from Xinyi Huili Fine Chemical Co., Ltd. (Xinyi, China). Triethylamine was purchased from Tianjin Damao Chemical Industry Co., Ltd. (Tianjin, China). N,Nʹ-dicyclohexyl carbodiimide (DCC) and 4-dimethylaminopyridine (DMAP) were purchased from Shanghai Medpep Co., Ltd. (Shanghai, China). 5-Methyl-2-oxo-1,3-dioxane-5-carboxylic acid (MCC) was prepared according to the reported literature [40]. All solvents and reagents used in this study were purified with standard methods.
Main-chain biodegradable liquid crystal materials base on diosgenin: synthesis and mesomorphism
Published in Liquid Crystals, 2021
Chaoxian Chen, Zhihao Guo, Jianshe Hu, Liqun Yang
Tosyl chloride was acquired from Shenyang Sinopharm Chemical Reagent Co., Ltd., China. Diosgenin was purchased from Wuhan Chemical Industry Co., Ltd., China. 1, 6-Hexanediol was purchased from Qingdao Lilai Fine Chemical Industry Co., Ltd., China. 1, 4-Dioxane was acquired from Shenyang Sinopharm Chemical Reagent Co., Ltd., China. Pyridine was purchased from Tianjin Damao Chemical Reagent Factory, China. Acetone was acquired from Tianjin Chemical Reagent First Factory, China. Ethyl acetate was purchased from Tianjin Bodi Chemical Co., Ltd., China. Furthermore, the monomer of 1, 3-Trimethylene carbonate and d, l-lactide were purchased from Jinan Biological Engineering Co., Ltd., China. All solvents and reagents used in this study were purified with standard methods.