Effect of coir content on mechanical and thermal properties of LLDPE/coir blend processed by rotational molding

Rotational Molding is a unique polymer processing technique that gives an advantage of having stress free end product. Majorly, Linear Low Density Polyethylene (LLDPE) is preferred as a base resin for rotomolding. However, incorporation of additives becomes necessary to improve mechanical properties and viscoelasticity as incumbent for few applications. The present research makes an attempt to investigate the effect of coir fiber on rotationally moldable LLDPE. Based on preliminary processing experiments, 10% or less Coir in its powder form when mixed with LLDPE was found to account a better flow ability as a prerequisite for roto moldability. Hence, the effect of 3%, 5%, 7% and 10% Coir mixed with LLDPE was experimented for the roto molded product to determine the mechanical properties, viz. tensile, flexural, hardness and impact strength. Also, the rate of heat transfer was evaluated subjected to the data recorded for mold, oven and internal air temperature when processing LLDPE/Coir considering different weight percentages. Crystallinity of the blend was examined based on DSC analysis for the distinguished percentage of coir incorporated in LLDPE. The experimental results depicted an improvised mechanical properties by 7% or less fiber addition, and beyond that, the properties were found to be regressed. The present work successfully engulfed Coir with LLDPE, producing a uniform distribution along the sides of the mold without applying any external pressure. Therefore, fiber integration in the rotomolding process is believed to be possible thus preserving homogeneous randomly distributed fiber dispersion.

Automated summary

This research investigates the effect of coir fiber on rotationally moldable LLDPE, finding that mechanical properties are improved with 7% or less fiber addition but regress beyond that. Additionally, the integration of coir with LLDPE produces a uniform distribution along the sides of the mold without applying external pressure. Fiber integration in the rotomolding process is believed to be possible, preserving homogeneous randomly distributed fiber dispersion.