Thermal investigation of γ‑cyclodextrin hydrates Full article
| Journal |
Journal of Thermal Analysis and Calorimetry
ISSN: 1388-6150 , E-ISSN: 1572-8943 |
||||
|---|---|---|---|---|---|
| Output data | Year: 2026, Volume: 151, Pages: 16877–16885 Pages count : 9 DOI: 10.1007/s10973-026-15300-1 | ||||
| Tags | γ-cyclodextrin hydrates · Dehydration · Vapor pressure · Phase transitions · Thermodynamic characteristics | ||||
| Authors |
|
||||
| Affiliations |
|
Funding (1)
| 1 | Russian Science Foundation |
Abstract:
γ-CD·nH2O hydrates with different n have been investigated by powder X-ray diffraction analysis (PXRD), static method and
differential scanning calorimetry (DSC). PXRD analysis of γ-CD·nH2O hydrates (n = 2.8–18.7) indicates the formation of
two different structures depending on the water content. The PXRD patterns in the range of n from 18.7 to ≈ 12.5 correspond
to the known literature structure of γ-CD·14.1H2O, while the diffractograms of γ-CD hydrates with lower water content
suggest the formation of a different structure.The pressure of saturated water vapor of γ-CD·nH2O hydrates (n = 4.8–13.5)
was measured by static method with membrane-gauge manometers in a wide range of pressure (240–88620 Pa) and temperature
(292–398 K) under condition of a slight change in the solid phase composition. The phase transition was revealed
at temperature T ~ 354 K, and its enthalpy is calculated from static data and compared with the value determined by DSC
data. The measured vapor pressure enlarges proportionally to the increase of the water content in the samples studied. Static
experimental data (p(T)), being reduced to a single composition γ-CD·1H2O, were approximated by the equations lnp(1/T),
which were used to compute the thermodynamic parameters of dehydration processes of the γ-cyclodextrin hydrates. The
obtained equations (lnp(1/T)) permit to calculate the vapor pressure of water in γ-CD·nH2O hydrates within the studied
temperature range for any n from 4.8 to 13.5. The information obtained was used to estimate Gibbs energy change during
the binding of water to the γ-CD framework.
Cite:
Zelenina L.N.
, Chusova T.P.
, Rodionova T.V.
, Laventosa Y.D.
, Rogov V.A.
, Manakov A.Y.
Thermal investigation of γ‑cyclodextrin hydrates
Journal of Thermal Analysis and Calorimetry. 2026. V.151. P.16877–16885. DOI: 10.1007/s10973-026-15300-1 WOS Scopus OpenAlex
Thermal investigation of γ‑cyclodextrin hydrates
Journal of Thermal Analysis and Calorimetry. 2026. V.151. P.16877–16885. DOI: 10.1007/s10973-026-15300-1 WOS Scopus OpenAlex
Dates:
| Submitted: | Jul 30, 2025 |
| Accepted: | Jan 2, 2026 |
| Published print: | Jan 22, 2026 |
| Published online: | Jan 22, 2026 |
Identifiers:
| ≡ Web of science: | WOS:001667772100001 |
| ≡ Scopus: | 2-s2.0-105028307174 |
| ≡ OpenAlex: | W7125382801 |