Environment aging of lignocellulosic fibers and their composites: Visual, mechanical, and microstructural aspects

The current experimental investigation reports the performance of intra-hybrid woven jute-sisal lignocellulosic fibers, and their polypropylene composites subjected to different aging conditions (distilled water, vegetable oil, and alkali solution) for a prolonged time of 6 months. The effect of different aging mediums on chemical composition of fibers, such as, variation in cellulose and hemicellulose content was analyzed to understand the degradation mechanisms and their structure property relationship established. Significant degradation in mechanical properties was observed with exposure to alkali followed by water mediums due to degradation of fibers and thereby results in poor interfacial characteristics, while sustained durability in terms of mechanical properties was observed with oil-based aging. Highest reduction was observed in tensile strength (11 % and 34 %), flexural strength (16 % and 20 %), tensile modulus (44 % and 58 %), and flexural modulus (51 % and 52 %) after 3-month and 6 months of alkali-aging, respectively as compared to un-aged specimens. Furthermore, the visual appeal of materials was significantly affected due to aging in an alkali solution followed by distilled water, while vegetable oil has not shown any visual degradation.