Preparation and characterization of low linear density polyethylene/plasticized jackfruit seeds starch blends

Abstract

The LLDPE/TPS blends were prepared in different blending formulation and additives. The formulation used were divided into 100:0, 95:5, 90:10, 80:20 and 70:30. Preparation of the blends are divided in three stages. The first stage involved preparation of TPS from jackfruit seeds starch. Jackfruit seeds were immersed in NaOH solution for two hours then was grinded into a size of 63 micron. The powdered starch was added with glycerol as plasticizers to become TPS. At second and third stage, LLDPE was blended with TPS in three different series which is controlled, compatibilised and silane treated. The polymer blend was prepared using heated two rolls mill at 150°C for 10 minutes. Several measurements were conducted such as tensile test, scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), water absorption and soil burial. Each formulation undergone tensile test to analyse their mechanical properties and the optimum blend ratio was chosen for subsequent studies. LLDPE/TPS for all series with TPS content 10 was found to be the optimum ratio and TPS content 0 and 30 were taken to further studies for comparison. Results showed that compatibilised and silane treated LLDPE/TPS blends have higher tensile strengths while TPS content higher than 10 will reduce tensile strength. However, compatibilised and treated LLDPE/TPS blends have better interfacial adhesion between polymer matrix and TPS and thus reduces water absorption percentage. SEM micrographs also showed that the formation of agglomerates and void is higher in high TPS content. Biodegradability of controlled series were found to be higher due to the weak interfacial interaction and easier microbial attack on TPS in LLDPE/TPS blends.