Irradiation of lignocellulose biomass of annatto seeds (Bixa orellana L.) for application in polymeric composites

The study of polymeric composites reinforced with vegetable fibers has become popular in the last decades since this type of material allows the reduction of both the biomass waste and the final cost of the polymer product. Plant fibers exist in large quantities, are inexpensive and combine biodegradability and renewal. In addition polymer-cellulose composites are more resistant to bending and impact than the same material exclusively made of polymer. Specifically the cellulose contained in the annatto seeds is present in a concentration around 40-45%, which becomes important for industrial use. In this work, the bagasse of annatto seeds after the removal of their reddish pigment was used to obtain high density polyethylene (HDPE) composites. The original material was used without and with a pretreatment which removed components such as residual pigment remnants, sugars, proteins and fatty acids. The remaining fibers were dried, fragmented and irradiated by electron beam at the doses of 10 kGy, 25 kGy, 50 kGy and 75 kGy to verify the effect of radiation on the cellulose structure and its subsequent effect on the polymer matrix