Direct One-step Synthesis of Cellulose Laurate Ester via Mechanochemical Method
This study presents a simple method for obtaining LCE with high degree of substitution(DS＞2.5)by directly utilizing microcrystalline cellulose(MCC),trifluoracetic anhydride(TFAA),and long chain lauric acid(LA).The impact of ball milling speed,grinding time,and feeding ratio on substitution,melting behavior,and thermal stability is thoroughly investigated.The results show that with increasing ball milling speed and time,LCE substitution increased and the melting temperature decreased.When the DS is larger than 2.81,LCE can be completely melted.Optimal conditions involve a feed ratio of 1:6:3,and ball milling at 400 r/min for 4 h yields cellulose laurel ester with a flow temperature(Tf)of 115 ℃ and a decomposition temperature of 324 ℃.In addition,the introduction of PVA into the system is explored to mitigate excessive TFAA and the side product trifluoroacetic acid.The results show that PVA not only fixed trifluoroacetic acid successfully but also had little effect on the melting and processing properties of the product.This strategy has significant advantages over conventional homogeneous methods,such as streamlining the preparation process,reducing monomer quantities,shortening reaction time,and promoting environmental friendliness.Its potential application in large-scale industrial production of thermoplastic cellulose derivatives is promising.
NETL
NSTL
万方数据
