Effect of Fiber Chemical Treatments on Rice Straw Fiber Reinforced Composite Properties

ABSTRACT

This work reports the effect of alkali, enzyme, and their sequential combination treatment on rice straw fiber properties (fiber diameter, aspect ratio, fiber length, bundle strength and elongation). The change in fiber properties and its association with rice straw fibers reinforced epoxy biocomposites has been studied. Biocomposites, prepared using the hand lay-up technique, were characterized using FTIR, TGA and SEM. The mechanical properties viz. tensile, flexural, impact and compression were measured according to the ASTM standards. Sound transmission loss and noise reduction coefficient of the composites was also determined. Results showed that the alkali and enzyme treatment to the rice straw significantly reduced fiber length and fiber diameter by 50%. Enzyme treatment caused the highest reduction in fiber diameter which increased the aspect ratio. The sequential combination of alkali and enzyme yielded significant improvements in the tensile (20%), flexural (22%), impact (98%), and compression (328%) strength of the composites. The noise reduction coefficient (0.95) of all rice straw composites was found excellent. Thus, alkali-enzyme pretreated rice straw fiber composite product is a good choice for agro-residue valorization and industrial product development.

摘要

本研究报告了碱、酶及其顺序组合处理对稻草纤维性能（纤维直径、长径比、纤维长度、束强度和伸长率）的影响. 研究了稻草纤维增强环氧生物复合材料的纤维性能变化及其与稻草纤维的关系. 利用FTIR、TGA和SEM对采用手糊技术制备的生物复合材料进行了表征. 根据ASTM标准测量机械性能，即拉伸、弯曲、冲击和压缩. 还测定了复合材料的声透射损耗和降噪系数. 结果表明，碱处理和酶处理使稻草的纤维长度和纤维直径显著减少50%. 酶处理导致纤维直径的最大减小，这增加了纵横比. 碱和酶的顺序组合显著提高了复合材料的拉伸（20%）、弯曲（22%）、冲击（98%）和压缩（328%）强度. 发现所有稻草复合材料的降噪系数（0.95）都很好. 因此，碱酶预处理稻草纤维复合产品是农残价值化和工业产品开发的良好选择.

KEYWORDS:

• Rice straw fiber
• alkali-enzyme combination treatment
• agro-residue
• mechanical properties
• biocomposites
• sound transmission

关键词:

• 稻草纤维
• 碱-酶联合处理
• 农业残留物
• 机械性能
• 生物复合物
• 声音传输

Acknowledgement

The authors are thankful to the Director, ICAR-Central Sheep and Wool Research Institute, Avikanagar, India for providing research infrastructure and all necessary testing facilities. Authors acknowledge S. A. Pharma Chem. Pvt. Ltd. Mumbai, India for providing the primafast cellulase enzyme. The material research center (MRC) of MNIT Jaipur is acknowledged for TGA analysis. Neenu Poonia is thankful to the Chaudhary Charan Singh Haryana Agricultural University, Hisar, India for the Ph.D. Merit scholarship.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the CCS Haryana Agricultural University, India [nil].