Class Id resinite from Canada: A new sub-class containing succinic acid

The analysis of European lacquer: optimization of thermochemolysis temperature of natural resins

“…A first group of markers (2,3,12,13,14,16,19,23,27, indicated with ° in figure 2) perform well at all temperature programs (UFD, 350, 480, 550°C). Differences between them are minimal.…”

“…For these small samples of diverse constitution, thermochemolysis gas chromatography-mass spectrometry, also called thermally assisted hydrolysis and methylation gas chromatography-mass spectrometry (THM-GC/MS), was chosen as principle technique, efficiently returning a maximum of information on the different ingredients with the use of only very limited sample amount. Thermochemolysis-GC/MS is today one of the most important techniques to analyze resinous materials in general [7][8][9][10][11][12][13][14][15][16][17][18][19], and it is a powerful method to analyze European lacquer as well [20,21].…”

“…Since the introduction of pyrolysis GC-MS with in situ derivatisation, tetramethyl ammonium hydroxide (TMAH) has been the preferred alkylation reagent for the analysis of modern natural resins [13]. Methylation of acidic and hydroxylic groups in combination with transesterification of esters and cleavage reactions can take place [19,22].…”

“…Also a double shot method combining a lower temperature thermal desorption at 250 or 300 °C, followed by high temperature pyrolysis (600 or 610°C) has been used successfully by some authors [7,18,34]; 550°C is also applied for varnish and lacquer analysis [3,8,35]. For the study of amber, thermochemolysis temperatures up to 650°C are applied [17,36], but after optimization study by Anderson [14], 480°C is frequently preferred, sometimes completed with an additional analysis at 300°C to show occluded compounds only [13,15,16,37,38]. Steadily increasing temperatures have been used rarely (200-700°C) [21].…”

Analytical pyrolysis with in-situ silylation, Py(HMDS)-GC/MS, for the chemical characterization of archaeological and historical amber objects

“…Such analytical approaches use bulk analysis to examine ambers and to obtain information on the botanical origins of archaeological findings. In addition, due to the high molecular weight/polymeric nature of ambers, some researchers have used analytical pyrolysis coupled with GC/MS systems (Py-GC/MS) [1,2,5,[20][21][22][23]. When analytical pyrolysis is used, the chemical composition of the sample is reconstructed on the basis of an interpretation of the molecular profile of the thermal degradation products of the original components, and on the recognition of specific molecular markers or molecular patterns, which give characteristic fingerprints of the pyrolysed material.…”