Premium
Solidification behaviour of organic eutectics and 1:1 addition compound: p‐Phenylenediamine‐resorcinol system
Author(s) -
Rai U. S.,
Mandal K. D.
Publication year - 1988
Publication title -
crystal research and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.377
H-Index - 64
eISSN - 1521-4079
pISSN - 0232-1300
DOI - 10.1002/crat.2170230706
Subject(s) - eutectic system , entropy of fusion , resorcinol , crystallization , phase diagram , thermodynamics , hydrogen bond , supercooling , chemistry , intermolecular force , fusion , crystallography , enthalpy of fusion , phase (matter) , molecule , organic chemistry , microstructure , differential scanning calorimetry , linguistics , physics , philosophy
The phase diagram of p‐phenylenediamine‐resorcinol system, determined by thaw‐melt method, shows the formation of a 1:1 molecular compound and two eutectics. The linear velocity of crystallization, determined by measuring the rate of movement of growth front in a capillary, indicates that crystallization data obey Hillig‐Turnbull equation:\documentclass{article}\pagestyle{empty}\begin{document}$$ v = u\left({\Delta T} \right)^n $$\end{document}Where u and n are constants and Δ T is undercooling. X‐ray diffraction data of the molecular compound, eutectics and pure components infer that these eutectics are not simply the mechanical mixture of the two components and there is preferential ordering of atomic planes during their formation. The infrared studies carried out on this system reveal the intermolecular hydrogen bonding between two components forming the molecular compound. Using experimental values of heats of fusion, entropy of fusion and excess thermodynamic functions were also calculated.