γ-戊内酯/水体系预处理竹屑制备L-CNF的研究

Preparation of L-CNF from Bamboo Sawdust Pretreated with γ-Valerolactone/Water System

关键词:  竹屑  γ-戊内酯  木质素  紫外屏蔽

Key Words:bamboo sawdust  γ-valerolactone  lignin  UV shielding

摘要:以废竹屑为原料，利用γ-戊内酯（GVL）/水体系预处理结合温和的均质处理，制备了含木质素的纳米纤维素（L-CNF），并探究了反应温度、反应时间、GVL与水的质量比等因素对竹屑纤维的理化性质和木质素含量的影响，并优化制备条件。结果表明，GVL/水体系预处理竹屑并未使纤维结构发生改变，纤维素的初级结晶结构仍保留，木质素含量降低。GVL/水体系预处理竹屑的最佳反应条件为反应温度140 ℃、反应时间10 h、GVL和水质量比4∶1，在此条件下成功制备了具有纳米尺寸（平均粒径(15.4±4) nm）和较高紫外屏蔽性能（在UVA和UVB区段紫外屏蔽率均在90%以上）的L-CNF。

Abstract:Lignin-containing cellulose nanofibrils （L-CNF） was prepared from waste bamboo sawdust using γ-valerolactone （GVL）/water system pretreatment combined with mild homogenization. The effects of reaction temperature， reaction time， and mass ratio of GVL to water on the physicochemical properties and lignin content of the bamboo sawdust fiber were investigated， and ultimately the preparation conditions were optimized. The results showed that the pretreatment of bamboo sawdust with GVL/water system did not change the structure of fibers， the primary crystalline structure of cellulose was still retained， and the lignin content was reduced. The optimum reaction conditions for the pretreatment of bamboo sawdust with GVL/water system were that reaction temperature of 140 ℃， the reaction time of 10 h， and the mass ratio of GVL to water of 4∶1， under which L-CNF with nano-size （the average particle size of (15.4±4) nm） and high UV shielding performance （UV shielding rate of more than 90% in both the UVA and UVB bands） were obtained.