Metallocene-Catalyzed Copolymerization of Ethylene and 1-Hexene in the Presence of Graphene/MgAl LDH Nanofiller: Effect on the Activity, SCB, and Thermal Stability

Nanofiller based on graphene and MgAl layered double hydroxides (G/LDHs) were synthesized successfully by co-precipitation method with varying graphene contents. The in situ polymerization of ethylene was conducted using 1-hexene as comonomer, zirconocene as a catalyst, MAO as co-catalyst, and G/LDHs as drop-in nanofiller. An increase in catalytic activity was recorded due to the addition of nanofiller. Furthermore, a maximum catalytic activity was observed for the nanofiller containing 100 mg of graphene. However, nanofiller containing higher amount graphene reduced the activity due to agglomeration of the graphene nanoparticles. Moreover, the degree of crystallinity decreased due to the addition of short chain branching in the copolymers. The thermal stability of the copolymers was analyzed using TGA. The effective activation energy (E_A) was calculated using the Friedman method. The E_A profiles thus obtained have revealed that the polymer nanocomposites having 100 mg of graphene have highest thermal stability than the neat copolymers.