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Published in Eli Ruckenstein, Hangquan Li, Chong Cheng, Solution and Surface Polymerization, 2019
Hongmin Zhang, Eli Ruckenstein
MAHE was prepared through the reaction between the sodium salt of trans, trans-2,4-hexadien-1-ol (HDO) and methacryloyl chloride. A 1000 mL round-bottom flask equipped with a condenser, a paddle stirrer, and a dropping funnel with a pressure-equalization arm was degassed and heated under reduced pressure. To this flask, 400 mL of CaH2-purified toluene was added, followed by the addition of sodium hydride (Aldrich; 60% dispersion in mineral oil; 10.4 g, 0.26 mol). Under the protection of nitrogen, 100 mL of toluene solution of HDO (25 g, 0.25 mol) was dropwise added in 1.5 h. The reaction mixture was stirred for 1 h at room temperature to generate the sodium salt of HDO. The reaction system was cooled to 0°C, and methacryloyl chloride (24 g, 0.22 mol) was dropwise added in 1.0 h. After about 1.5 h, the reaction was terminated by carefully adding an aqueous solution of sodium hydroxide (1.0 M, 100 mL). The reaction mixture was washed three times with water, evaporated to remove toluene, and distilled under reduced pressure (bp: 42°C/0.5 Torr; yield: 74% based on the amount of methacryloyl chloride employed). The monomer thus obtained was distilled twice over CaH2 and finally distilled in the presence of Al(C2H5)36 prior to polymerization. As shown later in Figure 1.1.3A, the chemical shifts and their intensities in the 1H NMR spectrum of the prepared MAHE are consistent with its molecular structure.
Systems Based on BN
Published in Vasyl Tomashyk, Multinary Alloys Based on III-V Semiconductors, 2018
KCN (1.0 M) and MeCN (200 mL) were placed in a 500-mL round-bottom flask with dropping funnel (Bernhardt et al. 2003b). At room temperature, BF3·Et2O (400 mM) was added dropwise with stirring. After further stirring (1.5 h) at room temperature, the solution was filtered and the filter residue was washed with MeCN (~300 mL). The combined acetonitrile phases were concentrated on a rotary evaporator. The title compound was obtained as a crude product. It was dissolved in H2O (200 mL) and concentrated HCl (30 mL) and Prn3N were added (35 mL). The obtained mixture was extracted with CH2Cl2(200 mL). The dichloromethane phase was dried with MgSO4and dissolved with KOH (25 g) in a little amount of H2O with vigorous stirring. The viscous aqueous phase was separated and washed with CH2Cl2. The product was extracted with MeCN (300 mL), dried with K2CO3, and concentrated on a rotary evaporator. The white K[BF2(CN)2] was washed with CH2Cl2and dried in vacuum.
Synthetic Polyphosphates Related to Nucleic and Teichoic Acids
Published in Stanislaw Penczek, H. R. Kricheldorf, A. Le Borgne, N. Spassky, T. Uryu, P. Klosinski, Models of Biopolymers by Ring-Opening Polymerization, 2018
Stanislaw Penczek, Pawel Klosinski
4-Acetoxymethyl-2-hydro-2-oxo-1,3,2-dioxaphospholane 74 (15.7 g, 8.72·10-2 mol) was distilled into a vacuum ampoule. This ampoule was equipped with a glass hammer and glass breakseal, containing 0.4379 g (2.2·10-3 mol) of (i-C4H9)3Al. 7.4 ml of dry CH2C1260 was distilled into the ampoule and then the vial containing initiator was broken directly in the solution of monomer. Polymerization was then conducted for 24 h at room temperature. After this time, approximately 20 ml of dry CH2Cl2 was added. The resulting mixture was poured into the three-necked round-bottom flask (equipped with thermometer, dropping funnel, and tube with CaCl2), and cooled down to – 20°C with stirring. Approximately 15% wt solution of N2O4 in methylene chloride was added dropwise until a persisting blue color of solution was obtained. This solution was left overnight at room temperature; the product was precipitating from the mixture during standing. The liquid was decanted and the polymer was first dried under vacuum and then twice precipitated from DMF solution into ethyl acetate. This procedure yielded 7.6 g (44%) of the colorless hygroscopic polymer.
Synthesis and properties of novel betaine fluorocarbon surfactants
Published in Journal of Dispersion Science and Technology, 2023
Wen Ren, Shuixiang Xie, Yuanpeng Cheng, Mingdong Zhang, Chunyang Wang, Jialuo Rong, Zongkun Li
The scheme for synthesis of FSC-m surfactants has been represented in Figure 2. 0.06 moles of perfluoroalkyl sulfonamide (1 equiv.) and ethanol (100 mL) were added to a three-neck round-bottom flask equipped with a condenser, mechanical stirrer, thermometer, and heating system.0.072 moles of aqueous sodium chloroacetate (1.2 equiv.) was slowly added with the aid of a dropping funnel, and the pH was adjusted to 8.8 using NaOH solution. The reaction mixture was then heated at 70 °C for 10 h, and the concentrated solution produced by rotary evaporation was slowly dripped into hot ethanol (50 °C, 100 ml) to precipitate the crystals, which were then filtered. The mixed solution was then dissolved with acetone, and filtered to obtain yellow solid FCC-m. The yield of FCC-m was over 53.2%.
Poly(butylene trisulfide)/SiO2 nanocomposites: cure and effect of SiO2 content on mechanical and thermophysical properties
Published in Journal of Sulfur Chemistry, 2022
Milad Sheydaei, Milad Edraki, Issa Mousazadeh Moghaddampour, Ebrahim Alinia-Ahandani
Na2S3 was synthesized according to the procedure described in the literature [19,21,48,49]. Briefly, NaOH (16 g) was dissolved in distilled water (400 mL) and heated to the boiling point. Next, Sulfur (18.75 g) was added to the solution and stirring was continued until complete dissolution of the sulfur, and after 1 h, the mixture was cooled to room temperature. For the synthesizing of PBTRS, 100 mL of Na2S3 solution and 60 mL of ethanol was added to a 250 mL four-necked round bottom flask equipped with a stirrer, a dropping funnel, a condenser, and a thermometer. Next, stirred with constant stirring at 600 rpm and the flask was heated to 75°C, and afterward 25 mL of DCB were gently added through a dropping funnel during 60 min. After synthesis, the PBTRS was filtered and washed by distilled water and HCl to remove inorganic salts, and then PBTRS was vacuum-dried at 25°C for 24 h.
Poly(ethylene disulfide)/carbon fiber composites: cure and effect of fiber content on mechanical and thermal properties
Published in Journal of Sulfur Chemistry, 2021
Milad Sheydaei, Milad Edraki, Ebrahim Alinia-Ahandani, Erfan Nezhadghaffar-Borhani
Na2S2 was synthesized according to the procedure which was described in the literature [2,5,18]. NaOH (16 g) was dissolved in distilled water (400 mL) and heated to the boiling point. Sulfur (12.5 g) was added to the solution and stirring was continued until sulfur completely was dissolved. After 3 h, the reaction medium turned to brownish orange. Upon cooling the mixture down to the room temperature, the solution was filtered. For the synthesizing of the PEDS, 100 mL of Na2S2 solution was added to a 250 mL four-necked round bottom flask equipped with a stirrer, a dropping funnel, a condenser, and a thermometer. The Na2S2 solution was stirred with constant stirring at 700 rpm and then, the flask was heated to 75°C, and subsequently, 25 mL of ethylene dichloride was gently added through a dropping funnel during 60 min. Then, produced polymer was filtered and washed by distilled water and HCl to remove the inorganic salts. Finally, the product was vacuum-dried at 30°C for 24 h. For the preparation of composites; the CF firstly was dispersed in 20 mL deionized water by ultra-sonication. Afterwards, Na2S2 was added to the following solution and the polymerization was carried out as before. The prepared solution contained 1, 1.5, and 2 mass % CF, respectively.