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Partially codified, structurally intact latex fibers("Aflenhaar") found in a low-rank coal have been characterized by various analytical methods. It has been proposed in previous studies, and it appears to be so here, that the latex was "naturally" vulcanized during the coalification period. The Affenhaar samples studied here are high in sulfur. However, the sulfur constituents were not extracted in the pyridine solvent used to exact the hydrocarbons. Two fossilized latex samples recovered from different locations within the brown coal deposit were characterized. Pyridine extracts of the samples were analyzed by capillary gas chromatography, combined capillary gas chromatography-mass spectrometry, and high-resolution mass spectrometry. Twelve compounds in the extract were tentatively identified as amyrin and hopane biomarker derivatives by comparing the Kovats retention indices, mass spectra, and order of elution with those in the literature. Three of these. identifications were verified by cochromatography with authentic standards.Kovats retention indices for the twelve compounds are reported.

Dimethyl polysulfides have been reported in the supercritical methanol extracts of coal and in the pyrolysis products of a high-sulfur Spanish coal that was first extracted with a mixture of dichloromethane and methanol. Dimethyl polysulfides and other products are shown to be formed by the reaction of methanol with elemental sulfur at elevated temperature and pressure. This reaction is a possible source of some of the dimethyl polysulfides observed by others in high-temperature methanol extracts.

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Abstract. Thermoanalytical techniques are commonly used to evaluate the oxidative stability of polyolefin resins. The most common technique for this evaluation is the oxidative induction time (OIT) as measured by DSC. This study compares the OIT values for a standard set of polyethylene samples with stability measurements made using other DSC and TG methods as well as a less common photothermal analysis method. The methods were all shown to give comparable results that could be correlated with oxidative stability. Interpretation of the measurements in terms of the resin properties is a significant problem in all thermoanalytical methods.