纳米银/纳米二醛纤维素气凝胶的制备及表征

Preparation and Characterization of Nano Silver/Nano Dialdehyde Cellulose Aerogels

关键词:  高碘酸钠  二醛纤维素  纳米银  气凝胶

Key Words:sodium periodate  dialdehyde cellulose  silver nanoparticles  aerogels

摘要:使用漂白硫酸盐针叶木浆为原料，以经高碘酸钠氧化后制备出的二醛纤维素为基材负载纳米银颗粒，后经高压均质法得到载银量为24.78%的纳米银/纳米二醛纤维素气凝胶。探讨高碘酸钠氧化反应时间对构成漂白硫酸盐针叶木浆的纤维素大分子以及针叶木纤维的影响。通过傅里叶变换红外光谱仪、X射线衍射仪、紫外可见分光光度计、扫描电子显微镜、透射电子显微镜和比表面积和孔径分析仪对样品进行表征。结果表明，随着氧化时间的增加，纤维素的醛基含量持续上升，当反应4 h时增至3300 µmol/g，纤维的聚合度由1447大幅下降至525，同时零距抗张强度和长度也呈现下降趋势。制备出的载银气凝胶上负载的纳米银颗粒为球形，气凝胶的比表面积为35.40 m²/g ，平均孔径为19.62 nm。

Abstract:Nanosilver particles were supported by dialdehyde cellulose which was prepared by using bleached kraft softwood pulp (BKSP) as raw material, and being oxidized by sodium periodate. Then silver nanoparticles/dialdehyde cellulose aerogels loaded with 24.78 % nanosilver were obtained by high pressure homogenization method. The impacts of sodium periodate oxidation pretreatment reaction time on the cellulose and fiber of BKSP were investigated and the examples were characterized by using FT-IR, XRD, UV-vis, SEM, TEM and BET. The results showed that with the increase of oxidation time, the aldehyde group content of cellulose increased to 3300 µmol/g, the degree of polymerization of the pulp decreased significantly from 1447 to 525. At the same time, the zero span tensile strength and fiber length also showed a downward trend. Nanometer silver particles in cellulose aerogels were spherical structures. The specific surface area of aerogels was 35.40 m²/g and the average pore diameter was 19.62 nm.