Oleic acid monomer and benzoyl peroxide effect on grafting degree and thermal properties of LLDPE grafted with oleic acid in solvent system

Abstract

This study reports that oleic acid monomer and benzoyl peroxide initiator have affected the thermal properties and morphological of linear low-density polyethylene (LLDPE) grafted with oleic acid (OA) in a solvent system. This study aimed to determine the effect of increasing the OA monomer and benzoyl peroxide (BPO) initiator concentration on the grafting degree and thermal properties of LLDPE grafted with OA (LLDPE-g-OA). This research was conducted by dissolving LLDPE in xylene via the reflux method at 140 ℃, then adding an OA monomer and BPO initiator. The purification process with acetone and methanol was carried out to obtain purified LLDPE-g-OA. The results showed that the addition OA monomer of 15% and BPO of 5% obtained the maximum grafting degree (GD) percentage of all variations. A small band at 1707.1 cm−1 is the carbonyl group of OA, indicating that OA has been grafted onto LLDPE. Thermal properties indicate that LLDPE-g-OA is a semi-crystalline compound with a melting point of 123.1 ℃ and a decomposition temperature of 475.4 ℃. The morphology of LLDPE-g-OA has resulted in changes in the surface structure after grafting with oleic acid.