Binary Mixtures of n-Alkanes. Phase Diagram Generalization: Intermediate Solid Solutions, Rotator Phases

New insights on the crystalline forms in binary systems of n-alkanes: Characterization of the solid ordered phases in the phase diagram tricosane + pentacosane

“…Indeed, experimental results on this system and on other binary systems and, in particular, on C 26 1 C 28 (the subject of another paper) have enabled us to characterize for the first time the three intermediate forms and to propose, therefore, a new phase diagram for the binary system C 23 -C 25 . The scope of this work is even wider since these phases are also observed in other binary systems [31][32][33][34][35][36][37][38][39][40][41] of n-alkanes [with a chain-length difference ͑Dn͒ equal to 1 or 2]. In other words, this paper leads to a complete characterization of all solid ordered forms observed in all binary systems of n-alkanes (the components belonging to the range C 16 to C 28 ).…”

“…The study of binary phase diagrams (temperature versus composition) has revealed a complex structural behavior of the mixed samples [28][29][30][31][32][33][34][35][36][37][38][39][40][41] where other forms than those seen in the components are observed and which are stabilized by mixing. The earliest binary phase diagram showing multiple one-phase domains at low temperature (temperature domain where the ordered phases are observed) is that of Lüth et al 28 for the system C 20 -C 22 .…”

“…Polymorphism of n-alkanes (C n H 2n12 ; hereafter denoted by C n ) and determination of binary phase diagrams [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41] in the alkane family have been reported on in recent years in numerous publications. The polymorphism of n-alkanes is rather well known where many solid-solid phase transitions have been observed as a function of temperature.…”

Ternary Mixtures of N-Docosane, N-Tricosane and N-Tetracosane

“…MEZCLAS TERNARIAS DE n-DOCOSANO, n-TRICOSANO Y n-TETRACOSANO Los diagramas de fases de los sistemas binarios : n-docosano : n-tricosano (C 22 24 H 50 and also the ternary phase diagram at room temperature.…”

“…On the basis of these results and of X-ray examination of forty one ternary mixtures, it is proposed the ternary phase diagram (C 22 H 46 : C 23 H 48 : C 24 H 50 ) at room temperature. This work has indicated the existence of limited terminal solid solutions near the three pure n-alkanes and three domains of orthorhombic intermediate phases (noted β' 1 , β'' 1 , β' 2 ) identical to those observed in the binary systems.…”