Restructuring of coir to microfibers for enhanced reinforcement in natural rubber

Microfibers were prepared from coir, an important lignocellulosic fiber, by chemico‐mechanical treatment. The microfibers with a diameter of 8–13 μm were incorporated in natural rubber and the resultant biocomposites were evaluated for the reinforcing effect of microfibers. Latex stage processing employed for composite preparation reduces fiber agglomeration and provide uniform dispersion of microfibers in the elastomer matrix. Microfiber/natural rubber composites were found to exhibit significant improvement in mechanical properties compared with unfilled and macrofiber filled composites. Microfibers showed higher thermal stability compared with untreated coir. However, degradation resistance of microfiber composites remain lower with respect to vulcanized natural rubber. POLYM. COMPOS., 40:414–423, 2019.