棉秆皮纤维的提取及其结构、性能研究

摘要

为更有效地利用废弃农作物秸秆资源,研究了常温常压碱处理提取天然棉秆皮纤维的技术,讨论了氢氧化钠溶液质量浓度、温度和时间等碱提取工艺参数对棉秆皮失重率的影响,并采用FT-IR、SEM、XRD等方法对优化工艺提取的棉秆皮纤维的化学成分、表面形态、结晶结构、力学性能等进行了表征.结果表明,NaOH质量浓度为15 g/L、液固比为30 mL/g、处理温度为100℃、处理时间为120min时,棉秆皮失重率较大,木质素、半纤维素、果胶等杂质去除较多.天然棉秆皮纤维结晶度为53.72％,断裂强度约1.6 cN·dtex-1,断裂伸长率为5.91％,性能接近天然纤维素纤维黄麻.%In order to utilize agricultural stalk resources sufficiently,cotton stalk bark was extracted by alkali treatment at normal pressure and temperature to produce cotton stalk fiber.The effects of alkali concentration,extracting temperature and time on weight loss of cotton stalk were investigated to optimize the extracting process.Scanning electron microscopy (SEM),Fourier transform infrared spectroscopy (FT-IR),and X-ray diffractometry (XRD) were employed to characterize the morphology,chemical composition,and structures of the produced cotton stalk fiber.The results demonstrated that the optimum alkali extraction conditions were sodium hydroxide concentration of 15 g/L,liquid-solid ratio of 30 mL/g,extraction temperature of 100 ℃,and extraction time of 120 min.The crystallinity of cotton stalk fiber was 53.72％,fracture strength was 1.6 cN · dtex-1,and elongation was 5.91％ at rupture,which were similar to natural fiber jute.