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81.
Self-assembling in systems poly(ethylene) imine-aminomethylated calix[4]resorcinarene-water-DMF (30 vol%) and catalytic properties of these compositions in hydrolysis of 4-nitrophenylbis (chloromethyl)phosphinate are studied. Critical concentrations of association, aggregates radii, and kinetic parameters of the reaction are established.  相似文献   
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A number of new acetals bearing phosphonium moieties with P-N bonds were prepared. Their condensation with resorcinols in acidic water-alcohol solutions was studied, which led to new phosphonium salts having a diarylmethane fragment.  相似文献   
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Russian Chemical Bulletin - Fluoroquinolone antibiotics (norfloxacin, ciprofloxacin, and moxifloxacin) modified at the piperazine ring by sterically hindered phenolic moieties were synthesized and...  相似文献   
86.
3-[2-(3,5-Di-tert-butyl-4-hydroxyphenylsulfanyl)acetoxy]2,2-bis[2-(3,5-di-tert-butyl-4-hydroxyphenylsulfanyl) acetoxymethyl]propyl 3,5-di-tert-butyl-4-hydroxyphenylsulfanylacetate was synthesized. Its structure was determined by means of 1H and 13C NMR spectroscopy and X-ray-diffraction analysis. This compound was found to possess high antioxidant activity in the conditions of auto-oxidation of low-pressure polyethylene.  相似文献   
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Russian Journal of General Chemistry -  相似文献   
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Mechanism and curing kinetics of bisphenol A epoxy resin–iso‐methyltetrahydrophthalic anhydride compositions using quaternary phosphonium salts as accelerators were investigated by differential scanning calorimetry (DSC) and electrospray mass‐spectrometry (ESI‐MS). The DSC method was applied to investigate curing kinetics and apparent activation energy values for the overall curing process. The DSC results showed that some of the phosphonium salts lead to a lower activation energy, that means they are more effective accelerators for the curing of epoxy–anhydride systems. The mechanism of curing was studied by ESI‐MS using the model reaction of epichlorohydrin (E) with phthalic anhydride (PA) in the presence of phosphonium salts or 2‐methylimidazole. Products containing the alkyl moiety of the phosphonium salt in form of alkyl esters could be identified. This suggests that the phosphonium salts activate the anhydride by electrophilic attack. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1088–1097  相似文献   
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