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1、See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/5348661New procedure for the determination ofHansen solubility parameters by means ofinverse gas chromatograph

2、yArticle in Journal of Chromatography A · July 2008DOI: 10.1016/j.chroma.2008.05.020 · Source: PubMedCITATIONS23READS583 authors, including:Adam VoelkelPoznan University of Technology185 PUBLICATIONS 1,819

3、CITATIONS SEE PROFILEAll in-text references underlined in blue are linked to publications on ResearchGate,letting you access and read them immediately.Available from: Adam VoelkelRetrieved on: 23 July 2016K. Adamska et

4、 al. / J. Chromatogr. A 1195 (2008) 146–149 147Fig. 1. 3D Hansen “room”.solvents are divided into good solvents and non-solvents accordingto the measured solubility. The three Hansen parameters create a3D “room” in which

5、 every material is represented by a single point,see Fig. 1. The miscibility or solubility of two substances is the bet-ter the smaller the distance is between the substances in Hansen“room”.Unfortunately, this method do

6、es not lead to a well-definedresult. The separation into good solvents and non-solvents is arbi-trary and other boundaries for defining solvents will result indifferent final Hansen parameters. Moreover, this method “pro

7、-duces” HSP values at room temperature useless in examination ofe.g. polymer blends at elevated temperatures.In inverse gas chromatographic experiment the investigatedmaterial (stationary phase) is placed into the chroma

8、tographic col-umn. The volatile compounds (test solutes) are injected into thecolumn and transported over the examined material by a carriergas. Each test solute interacts with investigated material. Magni-tude of this i

9、nteraction reflects in the value of specific retentionvolume (Vg) and is further presented as the Flory–Huggins interac-tion parameter (?).The relationship between chromatographic and thermody-namic data is given below [

10、22]:? = ln? 273.15Rp0 1VgMr,1?? p0 1RT (B11 ? V1) + ln ? ?1?2?? ?1 ? V1V2?(4)where Mr,1, p0 1, B11, Vg, V1, V2, ?1, ?2 are the molecular mass, satu-rated vapor pressure of the test solute, second virial coefficient ofthe

11、 test solute, specific retention volume of the test solute, molarvolume of the test solute, molar volume of the examined material,density of the test solute and density of the examined material (sur-factant, polymer) at

12、the temperature of measurement, respectively.Interaction parameter has been considered as a Gibbs freeenergy parameter and such assumption allows dividing interactionparameter ? into entropy ?S and enthalpy ?H components

13、 [23]:? = ?S + ?H (5)The enthalpy term can be calculated from the Hildebrand-Scatchard regular solution theory and entropy term should havea value of approximately 0.2 to 0.4 [9], 0.3 to 0.4 or 0.34 [9,24].The enthalpy c

14、omponent is related to solubility parameters oftwo components, according to Hildebrand-Scatchard theory, by therelation:?H = V1RT (?1 ? ?2)2 (6)where ?1 and ?2 are the solubility parameter solvent and polymer,respectivel

15、y and V1 is the solvent molar volume [24].The use of Eq. (6) with Flory–Huggins Eq. (5) gives:? = ? V1RT?(?1 ? ?2)2 + ?S (7)Guillet and co-workers [15,16] proposed to estimate the solubilityparameter of polymers by using

16、 the modification of Eq. (7):?2 1RT ? ?Vi = 2?2RT ?1 ?? ?2 2RT + ?∞ s Vi?(8)Voelkel and Janas [25] proposed to extent the Price’s procedure [26]for calculation of Hansen’s three component parameters. Values ofeach compon

17、ents of the total solubility parameter can be calculatedfrom the slope of straight line by using the following relationships:(a) ?d = mn-alkanes × RT2(b) ?p = (m1 ? mn-alkanes) × RT2(c) ?h = (m2 ? mn-alkanes) &

18、#215; RT2(9)where mn-akanes = value of the slope for n-alkanes; m1 = value of theslope for aromatic hydrocarbones, ketones, 1-nitropropane, ace-tonitrile, 1,2-dichloroethane; m2 = value of the slope for alcohols,1,2-diox

19、ane and pyridine. Value of the total solubility parameter isobtained from Eq. (3).The use of this procedure requires the careful selection of thetest solutes to groups representing different intermolecular inter-actions.

20、 Possible error may lead to significant differences in the finalresults which will be presented in Section 3.Values of the components of the solubility parameter can beestimated by using experimental data of the interact

21、ion parameter? and HSP literature data of test solutes, used in IGC measurements.In this case the Flory–Huggins theory can be applied. Accordingto this theory critical values of the interaction parameter ?cn iscalculated

22、 as follows [23]:?cri = 12?1 +?V1 V2? 2(10)where V1 and V2 denote molar volume of test solute and examinedmaterial, respectively.Selection of test solutes for further calculations is based on thecondition:? < ?cri (11

23、)These test solutes, for which experimental value of the interactionparameter is higher than critical value, are used in further calcu-lations. Value of respective Hansen solubility parameter, e.g. ?d,for examined materi

24、al is calculated as the arithmetic mean of thevalues of this parameter for all selected test solutes.Eq. (11) describes thermodynamic compatibility, miscibilitybetween a polymer and a solvent. Choi et al. [18], according

25、 to?cri assumption, presented the method of estimation of the Hansensolubility parameters for selected group of surfactants.Aim of this paper is the presentation of the new procedure forestimation of HSP values leading t

26、o realistic values. These physic-ochemical data will be accessible at different temperatures whatenables the prediction of behavior of various excipients, e.g. at ele-vated temperatures.2. Materials and methodsThe examin

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