Abstract:

Long-chain fatty acid esters of cellulose were synthesized in cellulose LiCl/DMAc（lithium chloride/N,N-dimethylacetamide）homogenous solution system by using p-toluenesulfonyl chloride as co-reaction reagent，and in situ activation of the long-chain fatty acid. The structure and properties of long-chain fatty acid esters of cellulose were characterized by means of IR, ¹H NMR, XRD, TG, etc. The esterification conditions were investigated. The results showed that the long-chain fatty acid esters of cellulose with the highest degree of substitution（DS）could be prepared when the esterification was carried out at 85℃ for 24 h with the mole ratios of repeat units of cellulose（AGU）∶long-chain fatty acid (RCOOH)∶ p-toluenesulfonyl chloride (TosCl) =1∶3∶3, and the degree of esterification decreased with the growth of the number of carbon atoms of long-chain fatty acid. TG analysis revealed that esterification weakened the inter-molecular and intra-molecular forces of celluloseN,N-二甲基乙酰胺（DMAc）均相溶液体系中，以对甲苯磺酰氯（TosCl）为共反应剂，原位活化脂肪酸（RCOOH），合成了长链脂肪酸纤维素酯。采用红外光谱、核磁共振谱、X射线衍射、热重等分析手段对产品进行了表征。考察了脂肪酸含碳原子个数、反应物配比、反应温度、反应时间等酯化条件对产品取代度的影响。结果表明：当反应物纤维素葡萄糖苷（AGU）∶RCOOH∶TosCl=1∶3∶3,反应温度为85℃，反应时间为24 h时，产品取代度最高，且随着长链脂肪酸碳原子数目的增加,<