泥炭藓纳米纤维素的制备及其在海藻酸钠复合膜中的应用研究

Preparation of Sphagnum Nanocellulose and Its Application in Sodium Alginate Composite Films

中文关键词: 泥炭藓  纳米纤维素  表征  海藻酸钠  复合膜

英文关键词: Sphagnum  nanocellulose  characterization  sodium alginate  composite film

中文摘要:

      目的 选取泥炭藓作为苔藓植物门的代表植物，探讨以泥炭藓为原料制备纳米纤维素的可行性，考察制得的泥炭藓纳米纤维素在海藻酸钠复合膜中的应用性能，拓宽苔藓化学内含物的应用范围。方法 采用烧碱法提取泥炭藓中的纤维素成分，通过硫酸水解法将提取到的纤维素转化为纳米纤维素。采用FTIR、XRD、热重、动态光散射、SEM及TEM技术对制备的泥炭藓纤维素(Sph-C)和泥炭藓纳米纤维素(Sph-NC)进行表征，检测制备的Sph-NC/海藻酸钠复合膜的力学性能。结果 FTIR分析显示，碱处理能够有效去除泥炭藓中的非纤维素杂质;XRD检测显示，Sph-C和Sph-NC中纤维素晶型均为纤维素I;热重分析显示，Sph-NC的热稳定性降低、固体残留率有所增加;TEM观察显示Sph-NC直径约为21.5 nm，属于纳米材料尺寸范畴。将Sph-NC用于海藻酸钠复合膜的制备，可将复合膜的抗张指数和耐破指数分别提高21.2%和15.7%。结论 泥炭藓可作为纤维素来源，用于制备纳米纤维素，制得的Sph-NC对海藻酸钠复合膜具有补强作用。

英文摘要:

      The work aims to Select sphagnum as the representative plant of the Bryophyta, discuss the feasibility of preparing nanocellulose from Sphagnum, and investigate the application performance of the prepared Sphagnum nanocellulose in the sodium alginate composite films, so as to expand the potential applications of chemical inclusions in bryophytes. The cellulose component in Sphagnum was extracted by soda pulping, and further transformed into nanocellulose by sulfuric acid hydrolysis. The prepared Sphagnum cellulose (Sph-C) and Sphagnum nanocellulose (Sph-NC) were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), dynamic light scattering (DLS), scanning electronic microscope (SEM) and transmission electronic microscopy (TEM). The mechanical properties of the Sph-NC/sodium alginate composite film were tested. FTIR showed that the non-cellulose impurities could be effectively removed from the Sphagnum by the alkaline treatment. XRD showed that the crystalline forms of cellulose in Sph-C and Sph-NC were both cellulose I. In the TGA, Sph-NC showed reduced thermostability whereas a higher residual mass. TEM observations revealed that the diameter of the prepared Sph-NC was approximately 21.5 nm, falling within the range of nanomaterial sizes. The tensile index and bursting index of the sodium alginate composite films increased by 21.2% and 15.7%, respectively, upon the addition of Sph-NC during the preparation process. It is concluded that Sphagnum can be used as a source of cellulose to prepare nanocellulose and the prepared Sph-NC plays a reinforcing effect on the sodium alginate composite films.