TY  - BOOK
AU  - Broadhurst,Martin G.
TI  - An Analysis of the Solid Phase Behavior of the Normal Paraffins
PY  - 1962///
PB  - [Gaithersburg, MD] : U.S. Dept. of Commerce, National Institute of Standards and Technology, 
KW  - Text
KW  - local
N1  - /pmc/articles/PMC5310682
N2  - A set of best values for the temperatures and enthalpies of fusion and transition for the n-paraffins is presented. From an analysis of these data a general qualitative theory of the phase behavior of the n-paraffins is developed. Four distinct crystal structures-hexagonal, triclinic, monoclinic, and orthorhombic-describe the solid phases of all n-paraffins with more than nine carbon atoms in the chain. The latter two structures become equivalent at longer chain lengths. Odd-even differences are resolved in terms of reasonable differences in end group packing, and the smooth increase in melting and transition temperature with increasing chain length is attributed to a decrease in the ratio of end groups to chain groups. Double transitions are predicted for several pure n-paraffins above n-C(34)H(70). Impurity effects are isolated from the pure n-paraffin properties and discussed. The equation, T(M)(°K) = 414.3 (n−1.5)/(n + 5.0) is presented as a correct description of the melting temperatures (T(M)) of all n-paraffins above n-C44H(90). Sufficient data to permit an accurate extrapolation of the enthalpies and entropies of fusion to the infinite-chain limit are not available
UR  - http://dx.doi.org/10.6028/jres.066A.024
ER  -