Latent heats organic compounds

Table XXV-3.—Latent Heats of Vaporization of Organic Compounds...

Some heats of sublimation of organic compounds calculated from the Clapeyron-Clausius formula ( 7.VIIIL) were in disagreement with Trouton s rule as calculated ( 14.VIIIL) for 4=4—4 and are of doubtful accuracy. They increased in the order ortho-, meta-, and para- compounds for dinitro-benzenes and nitroanilines, but the theoretical deductions made would be more interesting if greater confidence could be attached to the experimental results. The calculation of latent heats of sublimation from lattice theory is mentioned in 15.IXN. 

For different applications, there are different U/F ratios and B-stage oligomers. They can be stabilized by hexamethylene tetramine to keep them alkaline, or they can be reversibly etherifled with methanol or butanol to make them stable and soluble in organic solvents (Fig. 3.10). They may be compounded and processed in water or organic solution or as solid powders for different applications. For final cnre, they are compounded with latent acid catalysts such as ammonium sulfamate, ammonium phenoxyacetate, ethylene sulfite, and trimethyl phosphate and generally heated to accelerate the cross-hnking reaction. 

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