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The main thrust of this study is to examine the thermal decomposition of several metal chelates and of polypropylene, and to find how the two interact with one another to produce a possible flame retardant effect in the polymer. Several metal acetylacetonates were examined by thermogravimetric analysis (TGA) in order to determine their thermal stability with respect to atactic polypropylene (APP) and isotactic polypropylene (IPP). These chelates were not suitable so the benzoylacetonates and dibenzoylmethonates, (BA) and (DBM), were made of iron and chromium (III). These four chelates were found to be more thermally compatible with APP and IPP. The four chelates were pyrolyzed in both inert and oxidative atmospheres and their pyrolysis products were examined using chromatography and mass spectrometry and the combination of the two (GC-MS). The pyrolysis products were mostly aromatic aldehydes and ketones, from both the inert and oxidative atmosphere pyrolysis. A mechanism for the thermal degradation of these chelates was proposed. Polypropylene was pyrolyzed and the products were examined with capillary GC-MS. In an inert atmosphere the products of APP pyrolysis were hydrocarbons, mostly olefins. In oxidative pyrolysis, the products were primarily aldehydes and ketones. Proposed mechanisms for the thermal decomposition of APP in inert and oxidative atmospheres were examined and explained some of the observed products but not all of them. The pyrolysis of the head to head polypropylene was also examined and a mechanism was proposed which accounted for most of the pyrolysis products which were observed. One of the chelates, chromium benzoylacetonate, was added to the APP samples and lowered the total amount of volatiles produced by as much as 20%.

This dissertation considers the development of new analytical techniques to characterize shale oil, with emphasis on the heteroorganic compounds. A class separation precedure using preparative liquid chromatography on an amino-bonded silica support was developed to allow separation of shale oil into four chemical classes, namely: (1) hydrocarbons (alkanes/alkenes), (2) polynuclear aromatics, (3) acids and neutral polars, and (4) bases. This procedure was applied to the analysis of two different types of shale oil, Tosco II and In-Situ. All four classes of compounds were then characterized by capillary gas chromatography with flame ionization detection and some were also examined with the thermionic nitrogen specific detector. The acids and bases were further characterized by capillary gas chromatography with interfaced mass spectroscopy. Comparison of the two oils showed that although the level of heteroorganic compounds is different, the distribution of compounds within the same class is very similar. An argentation liquid chromatographic procedure was developed for isolation of the thiophenic compounds in shale oil. This is an important class of compounds to study since it encompasses approximately 80% of the organic sulfur content. Existing methods for isolation of thiophenes depend on a chemical reaction step. These methods fail to maintain the integrity of the thiophenes due either to discrimination dependent on the alkyl substituents present or to chemical alteration of some of the compounds. The argentation procedure avoided this discrimination since the retention time on the liquid chromatographic column was almost independent of the number and type of alkyl substituents on the thiophene ring. From direct comparison with the existing chemical methods, the argentation procedure was shown to be superior in recovering the thiophenes without discrimination.

The technique of alkali fusion reaction gas chromatography has been applied to the analysis and characterization of polycyanoalkylsiloxanes, polyalkoxysiloxanes, and poly-m-carboranylsiloxanes. A reaction system was designed to allow the efficient and quantitative conversion of the organo-functional and silicon-functional groups to products sufficiently volatile for gas chromatographic analysis. Milligram or less quantities of material were reacted at elevated temperatures in a flowing inert atmosphere for periods of 15 minutes or less. Upon completion of the reaction, the cryogenically trapped fusion products were flash volatilized onto the gas chromatograph column for separation and quantitation. A mini volume switching valve allowed the simultaneous occurrence of polymer fusion and product chromatography of a previous fusion. The average percent relative standard deviation was 1.2%. The thermal degradation properties of the poly-m-carboranylsiloxanes were studied by pyrolysis gas chromatography encompassing the ancillary techniques of selective element detection and mass spectroscopy. A gas chromatograph was interfaced with an atmospheric pressure microwave induced and sustained plasma emission detector for boron pyrolyzate analysis and an atmospheric pressure d.c. argon plasma emission echelle spectrometer for silicon pyrolyzate analysis. The use of selective element detection simplified the interpretation of the complex pyrograms and facilitated the mass spectral determination of the pyrolyzate structures. The thermal degradation of the poly-m-carboranylsiloxanes cannot proceed through an intramolecular cyclization pathway due to the steric restraints imposed by the presence of the carborane cage in the siloxane backbone. It was postulated that the m-carboranylsiloxanes depolymerize by an intermolecular pathway; the presence of cyclic siloxane pyrolyzates was shown to be consistent with this pathway.

Thermal analysis and analytical pyrolysis have been performed on selected phosphazene and silarylene-siloxane polymers for the following purposes: first, to investigate their low and high temperature behavior, secondly, to evaluate gas chromatography-element selective detection as a tool for analytical pyrolysis and lastly, to identify the pyrolysis products and to propose degradation mechanisms for these polymers. Thermal analytical techniques employed were differential scanning calorimetric (DSC) and thermal gravimetric analyses (TGA) as well as elemental analyses. For the phosphazenes, elemental analyses gave results consistent with those predicted from the repeating structures of the polymers. DSC and TGA data were also consistent with that reported for phosphazenes of similar structure in the literature. For the silarylene-siloxanes elemental analyses, DSC and TGA data were all inconsistent with data reported in the literature. Attempts to elucidate the reason(s) for these discrepancies using infrared, ('1)H NMR, and ('13)C NMR spectroscopies and gel permeation chromatography were inconclusive. Two methods of element selective detection were evaluated in the analytical pyrolysis studies. First, pyrolysis-gas chromatography-microwave induced atmospheric pressure helium emission spectroscopic detection (Py-GC-MED) was applied to the phosphazenes for element selective detection of carbon, phosphorus and halogens at three pyrolysis temperatures. Secondly, pyrolysis-gas chromatography-direct current argon plasma emission spectroscopic detection (Py-GC-DCP) was applied to the silarylene-siloxanes for element selection detection of silicon. Simultaneous carbon detection was accomplished by flame ionization detection (FID). The utility of both these plasma emission spectroscopic detectors for element selective fingerprint analysis of heteroatom containing polymers was demonstrated. Pyrolysis-gas chromatography-electron impact (EI) and chemical ionization (CI) mass spectrometry was used for the identification of pyrolysis products from both phosphazene and silarylene-siloxane polymers. A detailed degradation mechanism for poly{bis(2,2,2-trifluoroethoxy) phosphazene} was proposed based on the products observed. The presence of the D(,3), D(,4) and D(,5) dimethylcyclosiloxanes in the pyrolysis products of the silarylene-siloxane polymers indicated that intermolecular rearrangment of siloxane portions of the polymers most likely occurred. The results of this work illustrate the broad range of useful data obtainable using thermal analysis, element selective detection and mass spectrometry together in polymer pyrolysis studies.