Abstract Synthesis possibility of cellulose sulfates with a low and high degree of substitution (DS) by direct homogenous sulfation of cotton cellulose in N,N-dimethylacetamide/lithium chloride (DMA/LiCl) using SO3/pyridine (Py) complex was studied comprehensively. The sulfation reactions were carried at different temperatures, time durations, amount of the sulfating reagent and celluloses with varying weight average degree of polymerization (DPw). It was found that the method is very appropriate to prepare sodium cellulose sulfate (SCS) with low and high DS from celluloses having wide range DPw. Completely water-soluble SCS samples with regulable DS values from 0.23 to 2.56 were obtained. Suitable conditions were proposed to gain high sulfate content and the samples with DS values of 2.16–2.32, and yield of 69.4–77.8% could be prepared in these conditions. Celluloses with low and high DPw values exhibited similar reactivity for sulfation. Precipitation of the product and drastic depolymerization in the polymer chain have not occurred during the reaction.

中文翻译：

---

在 N,N-二甲基乙酰胺/氯化锂中均相合成 SO3/Py 可调节低取代度和高取代度的纤维素硫酸钠

摘要 综合研究了在N,N-二甲基乙酰胺/氯化锂(DMA/LiCl)中使用SO3/吡啶(Py)络合物对棉纤维素进行直接均相硫酸化合成低取代度和高取代度(DS)硫酸纤维素的可行性。硫酸化反应在不同的温度、持续时间、硫酸化试剂的量和具有不同重均聚合度 (DPw) 的纤维素下进行。发现该方法非常适合从具有宽范围 DPw 的纤维素制备具有低和高 DS 的纤维素硫酸钠 (SCS)。获得了完全水溶性的 SCS 样品，其 DS 值可在 0.23 至 2.56 之间调节。提出了合适的条件以获得高硫酸盐含量和DS值为2.16-2.32的样品，以及69.4-77的产率。在这些条件下可以制备 8%。具有低和高 DPw 值的纤维素表现出相似的硫酸化反应性。反应过程中没有发生产物的沉淀和聚合物链中的剧烈解聚。