Extraction and Characterization of Calotropis gigantea Bast Fibers as Novel Reinforcement for Composites Materials

ABSTRACT

The aim of this study is to scrutinize the use of Calotropis gigantea bast fibers as potential reinforcement in polymer composites. The bast fibers were extracted from the Calotropis gigantea plant bark and some of them were treated with alkali (5 wt.%) solution. The chemical composition, physico-chemical structural properties of the untreated and the alkali treated Calotropis bast fibers were studied. The results of chemical composition analysis indicated that alkali treatment removed most of the non-cellulose materials as confirmed by the FTIR analysis. The X-ray diffraction results exhibited that the crystallinity index of the alkali treated fibers increased in comparison with the untreated fibers, which agrees with the results obtained in the mechanical tests. The tensile strength and modulus of the alkali treated fibers were found to be higher whereas the elongation at break was lower than the untreated fibers. Thermal stability of alkali treated fibers was lower than that of the untreated fiber. Scanning electron micrographs showed roughening of the surface of the fiber due to the removal of the surface impurities and non-cellulosic components on alkali treatment.It can be concluded that alkali treatment is an effective method to improve the surface and mechanical properties of Calotropis bast fibers to be used in composite materials.

摘要

本研究的目的是审查牛角瓜麻纤维作为聚合物复合材料潜在的加固。韧皮纤维从牛角瓜植物的树皮，其中一些患者采用碱提取（5wt.%）解决方案。化学成分的处理和碱处理牛角瓜属韧皮纤维的理化结构性能的影响。化学成分分析结果表明，碱处理去除了大多数非纤维素材料，傅立叶变换红外光谱分析证实了这一点。的射出光线衍射结果表明，处理后的纤维与未处理的纤维比较增加碱的结晶度指数，它在力学试验中获得的结果一致。碱处理纤维的拉伸强度和弹性模量较高，断裂伸长率低于未经处理的纤维。碱处理纤维的热稳定性比未经处理的纤维低。扫描电子显微照片表明粗糙的纤维由于表面杂质和非纤维素成分对碱处理去除表面。可以断定，碱处理是提高可用于复合材料的表面和牛角瓜属韧皮纤维力学性能的一种有效方法。

KEYWORDS:

• Alkali treatment
• Calotropis bast fibers
• chemical composition
• structural properties
• tensile properties
• thermal stability

关键词:

• 碱处理
• 牛角瓜属韧皮纤维
• 化学成分
• 结构特性
• 拉伸性能
• 热稳定性

Acknowledgments

One of the authors (R. Ramasamy) expresses to thank Dr. Paramasivam Parthiban (Prist University) and Dr. Vijaya Kumar Badathala (Vel Tech High Tech Dr. Rangarajan Dr. Sakunthala Engineering college) for their valuable suggestions and continuous encouragement to carry out this work.