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Information × Registration Number 0305U003260, 0104U000658 , R & D reports Title Phase equilibriums solid - liquid in systems on basis of polyethyleneglycols popup.stage_title Сольватация солей лужних металів в поліетиленгліколях та розробка шкали сольватуючої здібності розчинників Head Krasnopyrova A., Registration Date 03-03-2005 Organization Kharkov national university named after V.N. Karazin popup.description2 Establishment of solvatation laws of alkaline metals salts in polyethyleneglycols and development of solvatation abilities scale of solvents. Method of research: work is executed with use of modern radioanalytical methods (radionuclides X-ray fluorescent the analysis - RRFA and a method of radioactive indicatorsIR-spectroscopy, atomic-issue spectrometry). In researching works about the solubility of alkaline metals salts that took place in the , we have researched the NaCl, KCl, RbCl, CsCl solubility in glycols of series of HOCH2(CH2CH2O)nCH2OH (n=0 (EG), 1 (DEG), 2 (TEG), 3 (TTEG), 6 (PEG-300), 8 (PEG-400)). The solubility of NaCl, KCl was studied by means of atomic emission method, solubility of RbCl, CsCl was studied by means of X-ray fluorescent analysis (RRFA) at the temperature range of 298.15 K - 328.15 K with 5K step. Solubility of alkaline metals chlorides has been found to decrease with the increase of glycole molecular weight that may be due to the decrease of solvents dielectric permeability when molecular weight of glucoles increases. Inflection is observed in the dependence of solubility logarithm from inverse value of dielectric permeability. A stronger drop of salts solubility when dielectric permeability of solvents decreases occurs beginning with tetraethyleneglucole. Such a behaviour of solubility is likely to be concerned with the fact that besides dielectric permeability conformational changes of oxyethylenized glucoles molecules exert an essential influence upon alkaline metals chlorides solubility when the length of the chain increases. Polythermic research of alkaline metals chlorides solubility in glycols showed the dependence of solubility logarithm from the temperature to be of a linear character. We calculated thermodynamic characteristics of salts solubility process in the glucoles studied from the data of solubility temperature dependence.The dependences of solubility characteristics upon the number of oxyethyl groups have been found to be non-linear ones. The appearance of oxyethyl group in glycole molecule results in the change of enthalpy and entropy sign of solubility process. Obviously such a behavior of thermodynamic characteristics of the solubility process is determined by decrease of hydrogen bonds strength in the solvents studied when the number of oxyethyl groups increases and it is confirmed by IR-spectroscopic data. Product Description popup.authors popup.nrat_date 2020-04-02 Close