Isolation and acetylation of cellulose nanostructures with a homogeneous system

编号 020022205

推送时间 20200120

研究领域 林产化工 

年份 2020 

类型 期刊 

语种 英语

标题 Isolation and acetylation of cellulose nanostructures with a homogeneous system

来源期刊 Carbohydrate Polymers

期 第222期

发表时间 20190422

关键词 Cellulose nanostructures;  Acid hydrolysis;  Chemical modification;  Surface acetylation;  Degree of substitution; 

摘要 A homogeneous system for nanocellulose acetylation was investigated. Cellulose nanostructures (CNS) were obtained from microcrystalline cellulose, and modification was conducted to increase hydrophobicity and physico-chemical properties of the nanoparticles. Sulfuric acid and hydrochloric acid were used for the isolation. The CNS were characterized with dynamic light scattering, zeta potential, atomic force microscopy, Fourier-transform infrared spectroscopy, nuclear magnetic resonance, X-ray photoelectron spectrometry, degree of substitution (DS), X-ray diffraction (XRD), and thermogravimetric analysis. Nanostructures obtained with sulfuric acid showed lower particle sizes and lower thermal stability. After modification, the results indicated the substitution of OH groups in cellulose structure by acetyl groups. The XRD patter was considerably modified and it was verified that acetylation increased the thermal stability. Different methods were used to calculate the DS, and the differences between the methodologies were explained. The acetylated samples play an important role in the nanocomposites field, since the hydrophobic surface increase its applications.

服务人员 尚玮姣

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