Akhlaq Maida, Uroos Maliha
Centre for Research in Ionic Liquids, School of Chemistry, University of the Punjab, 54590 Lahore, Pakistan.
ACS Omega. 2023 Feb 21;8(9):8722-8731. doi: 10.1021/acsomega.2c08118. eCollection 2023 Mar 7.
Carboxymethyl cellulose (CMC) is a hydrophilic derivative of cellulose whose large volumes have been used in textile processing, protective coatings, detergents, papers, and drilling fluids, while cellulose gum, which is the purified form of CMC, has extensive applications in food, cosmetic, and pharmaceutical industries. Therefore, this work reflects the production of CMC by extracting cellulose with traditional and ionosolv methods from domestic matchstick waste, providing an in-depth view of the overall process where two different kinds of cellulose were obtained from two different pretreatments, and the influence of cellulose on the profile of CMC was checked. All of the procedures have been performed under optimized conditions to reduce the cost and maximize the productiveness. The results depict that cellulose extracted by the ionosolv method using a protic ionic liquid, tetramethylguanidinium hydrogen sulfate (TMG-HSO), is more degraded than that extracted by the traditional sulfide method using sodium sulfide (NaS) and sodium hydroxide (NaOH). Thus, the produced CMC-2 via ionic liquid-extracted cellulose has more yield, DS (2.3), purity (98.5%), and solubility with less salt and moisture contents than CMC-1 produced by the conventional method due to an effective substitution of the hydroxyl group by the carboxymethyl group. Further, instrumental analyses like FTIR, XRD, H NMR, C NMR, and SEM emphasize the results that CMC-2 has more reduction of the hydroxyl peak in FTIR, a more amorphous structure in XRD, intense peaks in NMR, and the roughness of the surface in SEM.
羧甲基纤维素(CMC)是纤维素的一种亲水性衍生物,其大量应用于纺织加工、防护涂层、洗涤剂、纸张和钻井液中,而作为CMC纯化形式的纤维素胶在食品、化妆品和制药行业有广泛应用。因此,这项工作反映了通过传统方法和离子溶剂法从家用火柴梗废料中提取纤维素来生产CMC的过程,深入展示了从两种不同预处理中获得两种不同纤维素的整个过程,并研究了纤维素对CMC特性的影响。所有步骤均在优化条件下进行,以降低成本并最大化生产效率。结果表明,使用质子离子液体硫酸四甲基胍(TMG-HSO)通过离子溶剂法提取的纤维素比使用硫化钠(NaS)和氢氧化钠(NaOH)的传统硫化法提取的纤维素降解程度更高。因此,通过离子液体提取的纤维素生产的CMC-2比传统方法生产的CMC-1具有更高的产率、取代度(2.3)、纯度(98.5%)以及更低的盐分和水分含量下的溶解度,这是由于羧甲基基团对羟基的有效取代。此外,傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)、氢核磁共振(H NMR)、碳核磁共振(C NMR)和扫描电子显微镜(SEM)等仪器分析进一步证实了结果,即CMC-2在FTIR中羟基峰的降低更多,在XRD中具有更无定形的结构,在NMR中有更强的峰,在SEM中有更粗糙的表面。