Alcohols, linear, melting points

Melting point (TM) data exist for a number of surfactants. Table 17.6 gives a compilation of Tm data. Values of TM of the linear alcohol ethoxylates range between 289 and 321 K. They increase with increasing length of the alkyl chain as well as the ethoxylate moiety. The values for the ionic surfactants are higher. Table 17.6 shows that the counterion is of influence on the I m of the salt. 

Petroleum Wax, Synthetic, occurs as an off white to white wax. It is a refined mixture of solid hydrocarbons, paraffinic in nature, prepared by the catalytic polymerization of ethylene or copolymer of ethylene with linear (C3-C12) alpha-olefins. Synthetic Petroleum Wax ranges in melting point from about 77° to 116° (170° to 240°F). It is most soluble in aromatic hydrocarbons and least soluble in ketones, in esters, and in alcohols. 

It should be added that the non-linear shape of log Vs = f(l/T) diagram (curve A, Fig. 1) in the temperature region proceeding the melting point of n-octadecanol is the result of the 7 — q polymorphic transition in the solid alcohol. Abrahamsson et al [27] and Tanaka et al [28] described precisely the 7 and a structures. 

Studies on melt-formed samples showed that mechanical loss peaks a processes) occur above the glass transformation but below the melting point for various crystalline polymers. Such mechanical loss processes have been reported for linear polyethylene (two processes) 41), polypropylene (77), poly (vinyl alcohol) (77), and polytrifluoromonochloroethylene 37). These have been attributed to motion in or of the crystalline regions. For linear polyethylene a NMR broad-line narrowing process 65) and a T minimum 20) are also found in this temperature region. 

Other alcohols from the Augusta facility include some production of ALCHEM 123 and 145 and ISALCHEM 123 and 145 alcohols. These alcohols are obtained from freeze fractionation of some of the LIAL 123 and LIAL 145 alcohols. This process is similar to the one practiced in the fats and oils industry called winterization. The neat alcohol is cooled with or without a solvent. The linear terminal alcohols have fairly high melting points and crystallize from the liquid. 

Table 1 Melting and boiling points of linear n-alcohols...

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