Analytical characterization of diterpenoid resins present in pictorial varnishes using pyrolysis-gas chromatography-mass spectrometry with on line trimethylsilylation

A procedure based on the technique of the pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) has been applied, in this work, in order to determine the composition of diterpenoid resin employed in art works. The method is based on the on line derivatization of these resins using hexamethyldisilazane (HMDS). Results obtained were compared with those previously reported in literature from Venice turpentine, Strasbourg turpentine, colophony, sandarac and Manila copal using this same method and with those others from in situ thermally assisted hydrolysis and methylation with tetramethylammonium hydroxide (TMAH). Canada balsam, copper resinate and Copaiba balsam have been also analyzed extending the scope of this method in the field of the analysis of artwork materials. Several non-reported trimethylsilylated derivatives of compounds present in the diterpenoid resins have been identified. An improvement in sensitivity has been obtained by using HMDS as derivatizing reagent, together with a better resolution of the most representative peaks. Additionally, this method reduces the number of pyrolytic fragmentation, recombination, dehydration and isomerization products formed during the pyrolysis process and, in consequence, more simplified chromatograms are obtained. Finally, the reported procedure has been successfully used for characterizing two diterpenoid resin-based varnishes present in the canvas painting "The Betrothal of the Virgin" (Anonymous, 17th century) which is included in the pictorial collection of Saint Joseph Church in Taormina (Italy) and the Magdalena Tryptich (Master of Alzira, 16th century, Valencia, Spain).     

Pd／C催化松节油异构反应过程分析

松节油是经松脂蒸馏分离出的中性油,其主要组分是α-蒎烯和β-蒎烯(C10H16)双环单萜烯[1].蒎烯可以开环异构为柠烯、莰烯单环萜烯.     

Gas chromatography/mass spectrometry characterization of historical varnishes of ancient Italian lutes and violin

The organic constituents of historical vanishes from two ancient Italian lutes and a Stradivari violin, kept in the Musée de la musique in Paris, have been characterized using gas chromatography-mass spectrometry. Results have been compared with the chromatograms and mass spectra of recent as well as old naturally aged reference materials. The three historical varnishes analyzed have been shown to be oil varnishes, probably mixtures of linseed oil with resins. Identification of diterpenoids and triterpenoids compounds, and of the resins that may have been ingredients of the varnishes, are discussed in this paper.     

用杂多酸催化处理的重质松节油组成分析

对用杂多酸催化处理过的重质松节油的组成进行了分析．结果表明：重质松节油中润β-石竹保的含量从24．6％下降到2．6％左右．将催化处理后的重质松节油精馏，得到了含量80％以上的长叶烯。     

松节油催化水化混合物的气相色谱分析

In industry,terpineol is obtained from catalytic hydration of turpentine oil. The products in this reactionare very complicated so that it is difficult to monitor the reaction process. By using GC with PEG-20M col-umn under temperature programnung condition,the author analysed the hydrated mixtures of turpentine oil. The separation of isomers of turpentine oil or terpineol and the precision of quantitative analysis are good.     

TEG-99环氧树脂的合成与性能研究

以松节油为原料合成出新型TEG - 99环氧树脂 ,研究了它分别与典型胺类、聚酰胺类及酸酐类固化剂的固化反应和固化产物的性能。结果表明 ,以松节油为原料合成TEG - 99环氧树脂的过程简单、稳定 ,产物具有与双酚A型环氧树脂相似的外观、理化性能、固化特征等 ,是松节油综合利用的一个有前景的途径     

新型萜烯马来酸酐醇酸树脂的合成与结构表征

利用廉价工业松节油与顺丁烯二酸酐、多元醇。油酸等原料,合成了一种色泽浅,性能良好的萜烯马来酸酐醇酸树脂。研究了合成反应条件,用FTIR谱、^1^HNMR、TGA等手段对产物结构进行了表征,并测定了树脂的性能。     

气相色谱法测定水中的松节油

研究了测定水中松节油的气相色谱法.采用二硫化碳萃取,DB-5型毛细管柱分离,氢火焰检测器(FID)检测水中松节油的含量.松节油浓度在1. 00～25. 0 mg/L范围内与色谱峰面积呈良好的线性关系,线性相关系数r=0. 9996.加标回收率为86. 3%～91. 3%,测定结果的相对标准偏差为8. 7%(n=6).该法可满足地表水环境质量标准的要求.     

松香产品中重质松节油成分的气相色谱/质谱法分析

利用水汽蒸馏提取法富集了松香产品中残留的重质松节油,经气相色谱／质谱联机分析,发现其主要由１９种单萜和倍半萜化合物组成,全部为香味物质（未知物除外）。为提高松香产品的品质和开发利用松香重质松节油提供了依据。     

Synthesis and Structure of Tetrahydro-4,7-ethanoisobenzofuran-1,3-dione Derivative

(1R,2R,3S,4R,7R)‐7‐Isopropyl‐6‐methylbicyclo[2.2.2]oct‐5‐ene‐2,3‐dicarboxylic acid anhydride (tetrahydro‐4,7‐ethanoisobenzofuran‐1,3‐dione derivative) adduct 2 was prepared via the isomerization of α‐pinene and β‐pinene in turpentine followed by the Diels‐Alder cycloaddition with maleic anhydride in the presence of phosphoric acid/iodine catalysis. The molecular structure of adduct 2 was characterized by IR, ¹H NMR, ¹³C NMR, ¹H‐¹H COSY, DEPT, HSQC, HMBC, 2D NOESY and MS spectra. The single crystal X‐ray crystallographic analysis of adduct 2 was performed, and the X‐ray powder diffractive spectrum of the sample adduct 2 is consistent with the diffractive spectrum calculated from the single crystal data. Therefore the structure and stereochemistry of adduct 2 was established based on extensive spectral data and single crystal X‐ray analysis.