摘要
在纤维素LiCl/N,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24h时,产品取代度最高,且随着长链脂肪酸碳原子数目的增加,产物酯化度下降。热重分析结果表明,酯化反应削弱了纤维素分子间及分子内的作用力,赋予了长链脂肪酸纤维素酯较低的热加工温度。长链脂肪酸纤维素酯在有机溶剂中的溶解度随取代度的增加而提高。
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 cellulose,and the long-chain fatty acid esters of cellulose was endowed with a lower thermal machining temperature.The products were soluble in various organic solvents,depending on the DS.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2010年第11期3014-3019,共6页
CIESC Journal
基金
新疆大学自然科学基金项目(XY080111)~~
关键词
长链脂肪酸酸
纤维素
共反应剂
酯化
long-chain fatty acid
cellulose
co-reagent
esterification
