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Discusses the characterization of natural resin shellac by reactive pyrolysis-gas chromatography in the presence of organic alkali, tetramethylammonium hydroxide. Determination of terpenic acids, aleuritic acid, several minor fatty acids and wax components of shellac; Distribution of acidic components for shellac samples produced in India and Thailand.

Determines styrene copolymer sizing agents in paper by pyrolysis gas chromatography. Use of styrene monomer derived from the styrene sequences; Determination of the amounts of sizing agents retained in paper samples; Interpretation of the amounts of sizing agents in paper by degree of sizing.

Abstract: Conventional methods used to analyze total fatty acids in wood generally require tedious and time-consuming pretreatments such as solvent extraction and hydrolysis of esterified fatty acids of fats. In this study, both total fatty acid composition and the yield from free and esterified fatty acids of fats in Acacia species were investigated using a rapid and direct method of thermochemolysis–gas chromatography (GC)–flame ionization detector (FID)/mass spectrometry (MS) with organic alkalis. Using tetrabutylammonium hydroxide (TBAH) at 300°C, thermochemolysis–GC–FID/MS gave total fatty acids including the fat origin as pyrolyzates with suppressed lignin fragment formation because of the basicity of TBAH compared to other organic alkalis: tetramethylammonium hydroxide and tetramethylammonium acetate. The obtained results of fatty acid composition were consistent with those obtained using conventional methods consisting of a series of procedures such as solvent extraction, hydrolysis, derivatization, and analysis by GC–FID/MS in fatty acid composition analysis. Furthermore, thermochemolysis–GC–FID gave a higher yield of total fatty acid than the conventional method, quantitatively reflecting the difficulty in solvent extraction of these components. Consequently, thermochemolysis–GC with TBAH promises to be a rapid and direct method to characterize total fatty acids in wood, avoiding artifacts by solvent extraction of wood. Furthermore, this method discriminated Acacia auriculiformis from Acacia mangium based on the observed fatty acid contents and selected individuals containing low total fatty acids to minimize paper sliding on a printer drum. [Copyright &y& Elsevier]

Presents a quantitative analysis of detailed lignin monomer composition by pyrolysis-gas chromatography. Contribution of the lignin acetylation procedure; Determination of the dehydrogenative polymers; Accuracy of the preacetylation in analyzing the detailed lignin monomer composition.