ジュレン酸化生成物および高純度無水ピロメリット酸のガスクロマトグラフによる定量
1970 年 13 巻 12 号 p. 959-962
詳細
1970 年 13 巻 12 号 p. 959-962
Programmed temperature gas chromatographic analysis of methylesters of durene oxidation products was carried out by using a column packed with Chromosorb-W coated with 30% Apiezon Grease L. The relative weight responses of dimethyl 4, 5-dimethylphthalate and tetramethyl pyromellitate to inner standard material (pentamethylbenzene) were determined, which were 1.15 and 1.65 respectively.
Pyromellitic dianhydride (PMDA) isolated from durene oxidation products has usually been contaminated with a small amount of pyromellitic monoanhydride (PMMA) and pyromellitic acid (PMA). The gas chromatographic separation of the above mixture was successfully accomplished by converting PMDA to dialkyl dimethyl pyromellitate, PMMA to alkyltrimethyl pyromellitate and PMA to tetramethyl pyromellitate respectively. The reactions involved were alcoholysis of anhydride ring with ethanol or n-propanol and esterification of free carboxylic group with diazomethane.
The best result was obtained when n-propanol was used in alcoholysis. The gas chromatographic analysis of purified PMDA was in good agreement with acid-base titration.
