As the annual production of industrial hemp in China increases and its global market share grows,its multipurpose development has become an important trend for future development.The cellulose mass fraction of industr...As the annual production of industrial hemp in China increases and its global market share grows,its multipurpose development has become an important trend for future development.The cellulose mass fraction of industrial hemp was found to be as high as 59.36%by chemical composition determination,providing a possibility for the production of nanocellulose.To broaden the application field of industrial hemp,the 2,2,6,6-tetramethylpiperidine-1-oxyl radical(TEMPO)-oxidized nanocellulose(TCNF),sulfuric acid hydrolyzed nanocellulose(SCNC),and lignincontaining hydrolyzed nanocellulose(LCNC)were prepared by multi-step chemical purification pretreatment combined with TEMPO oxidation and sulfuric acid hydrolysis,respectively.They were characterized by Fourier transform infrared(FTIR)spectroscopy,X-ray diffraction(XRD),and thermogravimetric analysis(TGA).The effects of the sodium hypochlorite volume,sodium hydroxide mass fraction in the pretreatment process,and acid hydrolysis reaction time on the Zeta potential and particle size of the prepared nanocellulose were investigated.The absolute value of the Zeta potential of SCNC could reach 29.59 mV,and the particle size was small.The suspension could still maintain good dispersion stability after standing for 24.0 h under the same dispersion conditions.The basic functional group composition and crystal morphology of TCNF,SCNC,and LCNC did not change compared with the raw hemp,and the highest crystallinity increased from 24.6%to 68.1%.Due to the introduction of ester and carboxyl groups,the initial degradation temperature and the temperature at the maximum mass loss rate of the nanocellulose were lower than those of the raw hemp,but the nanocellulose still maintained the thermal stability for practical applications.展开更多
基金Fundamental Research Funds for the Central Universities of China(No.2232024G-01)Textile Vision Basic Research Program,China(No.J202305)。
文摘As the annual production of industrial hemp in China increases and its global market share grows,its multipurpose development has become an important trend for future development.The cellulose mass fraction of industrial hemp was found to be as high as 59.36%by chemical composition determination,providing a possibility for the production of nanocellulose.To broaden the application field of industrial hemp,the 2,2,6,6-tetramethylpiperidine-1-oxyl radical(TEMPO)-oxidized nanocellulose(TCNF),sulfuric acid hydrolyzed nanocellulose(SCNC),and lignincontaining hydrolyzed nanocellulose(LCNC)were prepared by multi-step chemical purification pretreatment combined with TEMPO oxidation and sulfuric acid hydrolysis,respectively.They were characterized by Fourier transform infrared(FTIR)spectroscopy,X-ray diffraction(XRD),and thermogravimetric analysis(TGA).The effects of the sodium hypochlorite volume,sodium hydroxide mass fraction in the pretreatment process,and acid hydrolysis reaction time on the Zeta potential and particle size of the prepared nanocellulose were investigated.The absolute value of the Zeta potential of SCNC could reach 29.59 mV,and the particle size was small.The suspension could still maintain good dispersion stability after standing for 24.0 h under the same dispersion conditions.The basic functional group composition and crystal morphology of TCNF,SCNC,and LCNC did not change compared with the raw hemp,and the highest crystallinity increased from 24.6%to 68.1%.Due to the introduction of ester and carboxyl groups,the initial degradation temperature and the temperature at the maximum mass loss rate of the nanocellulose were lower than those of the raw hemp,but the nanocellulose still maintained the thermal stability for practical applications.
