Direct gas chromatographic measurement of activation parameters of unimolecular reactions

A direct gas chromatographic method, which uses the injection port as a con stant time thermal flow reactor, has been applied to obtain activation para meters for the di-tert-butyl peroxide unimolecular thermal decomposition re action (Delta H-270 degrees C(#) = 34.2 +/- 0.1 kcal/mol; Delta S-270 degre es C(#) = -2.0 +/- 0.1 cal/mol K; Delta G(270 degrees C)(#) = 35.3 +/- 0.7 kcal/mol) in the 240 degrees-300 degrees C temperature range. The applicati on of that technique also renders the corresponding values for the analogou s reaction of 3,6-diphenyl-1,2,4,5-tetroxane (Delta H-300 degrees C(#) = 20 .6 +/- 0.1 kcal/mol; Delta S-300 degrees C(#) = -31.3 +/- 0.2 cal/mol K; De lta G(300 degrees C)(#) = 38.5 +/- 0.1 kcal/mol), which belongs to the unim olecular thermolysis of its molecule.