Morphology and phase transitions of n-alkyl alcohol microcrystals
Tóm tắt
Phase transition behaviors and morphology of thin crystals of 1-heptadecanol and 1-octadecanol with sample masses from 3 μg to 1 mg were investigated by the high-sensitive DSC and AFM. The solid transition and the melting temperatures depressed with the decrease in sample mass. The phase transition behaviors were divided into three groups, the transitions were same to the bulk (more than 0.1 mg), the solid-state transition temperature depressed (from 0.1 to 0.03 mg), both the melting and the solid-state transition temperature depressed (<0.03 mg). The crystal morphologies of 0.1, 0.01, 0.005 mg sample were observed by AFM for the representative of each groups. The morphologies of crystals were classified into three groups, the large droplets with the curved shape, the middle droplets with flat and round shape and the polygonal shape. The crystal morphologies correlated with the phase transition behaviors.
Tài liệu tham khảo
Iwasa M, Emoto K, Wakairo R, Nishimura S, Yoshida H. Effect of thickness on phase transition of poly(ethylene oxide) thin film. Jpn J Thermophys Prop. 2012;26:203–8.
Tanaka K, Seto T, Hayashida T. Phase transformation of n-higher alcohols. Bull Inst Chem Res Kyoto Univ. 1957;35:123–39.
Abrahamsson S, Larsson G, von Sydow E. The crystal structure of the monoclinic form of n-hexadecanol. Acta Crystallogr. 1960;13:770.
Tasumi M, Shimanouchi T, Watanabe A, Goto R. Infrared spectra of normal higher alcohols. Spectrochim Acta. 1964;20:629.
Majewski J, Margulis L, Weissbuch I, Popovitz-Biro R, Arad T, Talmon Y, Lahav M, Leiserowitz L. Electron microscopy studies of amphiphilic self-assemblies on vitreous ice. Adv Mater. 1995;7:26–35.
Allara DL, Parikh AN, Judge E. The existence of structure progressions and wetting transitions in intermediately disordered monolayer alkyl chain assemblie. J Chem Phys. 1994;100:1761–4.
Dorset DL. Orthorhombic n-octadecanol: and electron diffraction study. Chem Phys Lipids. 1979;23:337–47.
Soutzidou M, Glezakou V-A, Viras K. Low-frequency raman spectroscopy of n-alcohols, LAM vibration and crystal structure. J Phys Chem B. 2002;106:4405.
van Miltenburg JC, Oonk HAJ, Ventola L. Heat capacities and derived thermodynamic functions of 1-octadecanol, 1-nonadecanol, 1-eicosanol, and 1-docosanol between 10 K and 370 K. J Chem Eng Data. 2001;46:90–7.
Ventola L, Ramirez M, Calvet T, Solans X, Cuevas-Diarte MA, Negrier P, Mondieig D, Van Miltenburg JC, Oonk HAJ. Polymorphism of N-alkanols: 1-heptadecanol, 1-octadecanol, 1-nonadecanol and 1-eicosanol. Chem Mater. 2002;14:508–17.
Berwanger R, Henschel A, Knorr K, Huber P, Pelster R. Phase transitions and molecular dynamics of n-hexadecanol confined in silicon nanochannel. Phys Rev B Condens Matter Mater Phys. 2009;79:125442/1–12.
Iwasa M, Kakinoki S, Emoto K, Yoshida H. Effect of crystal thickness on phase transition of n-alkyl alcohols. Netsu Sokutei. 2014;41:93–8.
Yasutake M, Watanabe K, Wakiyama S, Yamaoka T. Critical dimension measurement using new scanning mode and aligned carbon nanotube scanning probe microscope tip. Jpn J Appl Phys. 2006;45:1970–3.
Toda A, Miyaji H, Ogawa Y, Takamizawa K. Lateral habits of n-alkane single crystals. J Mater Sci. 1991;26:2793–6.