TEMPO 氧化和硫酸处理纤维素纳米晶体膜的水蒸气吸附性能。

Water vapor sorption properties of TEMPO oxidized and sulfuric acid treated cellulose nanocrystal films.

机构信息

College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China; College of Sciences, Central South University of Forestry and Technology, Changsha, 410004, China.

College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China.

出版信息

Carbohydr Polym. 2018 Oct 1;197:524-530. doi: 10.1016/j.carbpol.2018.06.027. Epub 2018 Jun 7.

DOI:10.1016/j.carbpol.2018.06.027

PMID:30007643

Abstract

For cellulose nanocrystal film, water adsorption is extremely important for its product performance. For gaining a deeper understanding of hygroscopic behavior, two cellulose nanocrystal films, such as TEMPO oxidized cellulose nanocrystal film (TOCNF) and sulfuric acid treated cellulose nanocrystal film (SACNF) were investigated using dynamic water vapor sorption apparatus. During the water vapor sorption process, the running time, real-time sample mass, target relative humidity (RH), actual RH and real-time temperature were all collected. Through the comparison of these collected data, significant differences in the equilibrium moisture content, sorption hysteresis and sorption kinetics were confirmed. It was important to note that TOCNF and SACNF had equilibrium moisture contents of 28.2% and 22.8, respectively, at a RH of 95%. Then, using parallel exponential kinetics (PEK) model, sorption kinetics data were accurately fitted. Furthermore, two Kelvin-Voigt elements were introduced to interpret the fitting results and calculate the modulus of TOCNF and SACNF.

摘要

对于纤维素纳米晶体薄膜而言，对其产品性能而言，水吸附极其重要。为了更深入地了解吸湿行为，使用动态水蒸气吸附仪研究了两种纤维素纳米晶体薄膜，即 TEMPO 氧化纤维素纳米晶体薄膜（TOCNF）和硫酸处理的纤维素纳米晶体薄膜（SACNF）。在水蒸气吸附过程中，收集了运行时间、实时样品质量、目标相对湿度（RH）、实际 RH 和实时温度。通过比较这些收集的数据，证实了平衡含水量、吸附滞后和吸附动力学之间存在显著差异。重要的是要注意，在 RH 为 95%时，TOCNF 和 SACNF 的平衡含水量分别为 28.2%和 22.8%。然后，使用平行指数动力学（PEK）模型准确拟合了吸附动力学数据。此外，引入了两个 Kelvin-Voigt 元件来解释拟合结果并计算 TOCNF 和 SACNF 的模量。