Process Chemistry Centre, Laboratory of Wood and Paper Chemistry, Abo Akademi University, Turku/Abo Fi, Finland.
Carbohydr Res. 2010 Apr 19;345(6):810-6. doi: 10.1016/j.carres.2010.01.007. Epub 2010 Jan 18.
Acetylated galactoglucomannans (GGMs) are the main hemicellulose type in most softwood species and can be utilized as, for example, bioactive polymers, hydrocolloids, papermaking chemicals, or coating polymers. Acetylation of spruce GGM using acetic anhydride with pyridine as catalyst under different conditions was conducted to obtain different degrees of acetylation on a laboratory scale, whereas, as a classic method, it can be potentially transferred to the industrial scale. The effects of the amount of catalyst and acetic anhydride, reaction time, temperature and pretreatment by acetic acid were investigated. A fully acetylated product was obtained by refluxing GGM for two hours. The structures of the acetylated GGMs were determined by SEC-MALLS/RI, (1)H and (13)C NMR and FTIR spectroscopy. NMR studies also indicated migration of acetyl groups from O-2 or O-3 to O-6 after a heating treatment in a water bath. The thermal stability of the products was investigated by DSC-TGA.
乙酰化半乳甘露聚糖（GGM）是大多数软木物种中主要的半纤维素类型，可用作生物活性聚合物、水凝胶、造纸化学品或涂料聚合物。本研究在不同条件下，使用醋酸酐和吡啶作为催化剂对云杉 GGM 进行乙酰化，在实验室规模上获得不同程度的乙酰化，而作为经典方法，它可以潜在地转移到工业规模。考察了催化剂和醋酸酐用量、反应时间、温度以及醋酸预处理的影响。通过将 GGM 回流两个小时可以得到完全乙酰化的产物。通过 SEC-MALLS/RI、（1）H 和（13）C NMR 以及傅里叶变换红外光谱法确定了乙酰化 GGM 的结构。NMR 研究还表明，在水浴中加热处理后，乙酰基从 O-2 或 O-3 迁移到 O-6。通过 DSC-TGA 研究了产物的热稳定性。
