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A concerted study of poly(vinyl chloride), chlorinated poly(vinyl chloride), and poly(vinylidene chloride) polymers by spectroscopy, thermal analysis, and pyrolysis‐gas chromatography resulted in a proposed mechanism for their thermal degradation. Polymer structure with respect to total chlorine content and position was determined, and the influence of these polymer units on certain of the decomposition parameters is presented. Distinguishing differences were obtained for the kinetics of decomposition, reactive macroradical intermediates, and pyrolysis product distributions for these systems. It was determined that chlorinated poly(vinyl chloride) systems with long‐chain CHCI units were more thermally stable than the unchlorinated precursor, exhibited increasing activation energy for the dehydrochlorination, and produced chlorine‐containing macroradical intermediates and chlorinated aromatic pyrolysis products. The poly(vinyl chloride) polymer was relatively less thermally stable, exhibited decreasing activation energy during dehydrochlorination, and produced polyenyl macro‐radical intermediates and aromatic pyrolysis products.

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than those obtained with the samples from the meteorites, but is typical of the performance obtained with the detector in this work. CONCLUSIONSEvaluations of the photoionization detector developed indicated it to be a highly sensitive and discriminating device of considerable long-term stability. The end of the hollow discharge cathode was clean even after approximately 500 hours

gave a , of 0.002, whereas at A = 0 (pure ra-butylamine) the observed viscosity (6 cps) gave a , of 0.157. From the specific gravity of the amine (0.74) and the 1 to 1 complex (0.80), 0i for 2 to 1 and 3 to 1 mixtures gave theoretical values of 0.019 and 0.033, respectively, compared to observed values of 0.031 and 0.052. The viscosity lowering as calculated from Equation 2 is 32 cps (observed 60 cps) for the 2 to 1 mixture and 20 cps (observed 30 cps) for the 3 to 1 mixture. This deviation from observed values is not unexpected (Irany, 1943), since these liquid mixtures do not form an ideal solution and neither liquid is nonpolar.Within the butylamine, the viscosity of the adduct increased from -> iso-> sec-> ¿erí-butylamine. This difference in viscosity appears to be too large to explain