School of Chemistry and Chemical Engineering, South China University of Technology, No. 381, Wushan Road, Tianhe District, Guangzhou 510640, Guangdong, China.
School of Chemistry and Chemical Engineering, South China University of Technology, No. 381, Wushan Road, Tianhe District, Guangzhou 510640, Guangdong, China.
Carbohydr Polym. 2015 Dec 10;134:458-66. doi: 10.1016/j.carbpol.2015.08.025. Epub 2015 Aug 13.
In order to develop a novel application for cellulose nanowhiskers (CNW) produced from the sulfuric acid hydrolysis of cotton, acrylamide (AM) was grafted onto the CNW. The graft reaction of the acrylamide-grafted CNW (AM-g-CNW) was confirmed by Fourier transform infrared spectroscopy (FTIR) and UV-vis spectroscopy. The carbon and nitrogen contents of the AM-g-CNW were measured by elemental analysis and X-ray photoelectron spectroscopy (XPS). The grafting ratios and average degrees of β-1,4-linked anhydro-D-glucose unit substitution were measured. The thermochemical properties of the AM-g-CNW were characterized using thermogravimetric analysis (TG). The glass transition temperatures were determined by differential scanning calorimetry (DSC). The degrees of crystallinity were measured by X-ray diffraction (XRD). The liquid crystalline properties of AM-g-CNW were observed by polarizing optical microscopy (POM). AM-g-CNW had the best grafting ratio, 12.77%, when the AM/CNW molar ratio was 3, c(K2S2O8)/n(CNW) was 0.15, the reaction temperature was 70 °C, and the reaction time was 60 min. The birefringence of AM-g-CNW was responsive to hydroxide ions, which might be useful in applications that benefit from sensitivity towards different ionic species.
为了开发一种新型纤维素纳米纤维（CNW）的应用，采用硫酸水解棉花制备的 CNW，接枝丙烯酰胺（AM）。通过傅里叶变换红外光谱（FTIR）和紫外可见光谱证实了丙烯酰胺接枝 CNW（AM-g-CNW）的接枝反应。通过元素分析和 X 射线光电子能谱（XPS）测定了 AM-g-CNW 的碳氮含量。通过测定接枝率和平均 β-1,4-脱水-D-葡萄糖单元取代度来测定接枝率和平均 β-1,4-脱水-D-葡萄糖单元取代度。采用热重分析（TG）对 AM-g-CNW 的热化学性质进行了表征。通过差示扫描量热法（DSC）测定了玻璃化转变温度。通过 X 射线衍射（XRD）测量了结晶度。通过偏光显微镜（POM）观察了 AM-g-CNW 的液晶性能。当 AM/CNW 摩尔比为 3、c(K2S2O8)/n(CNW)为 0.15、反应温度为 70°C 和反应时间为 60min 时，AM-g-CNW 的接枝率最高，为 12.77%。AM-g-CNW 的双折射对氢氧根离子有响应，这在受益于对不同离子种类的敏感性的应用中可能是有用的。
