Studies on Magnetic Pigmented Polyester Composites

Abstract

New polymer composites based on an unsaturated polyester matrix and magnetic pigmented filler were prepared and tested for their mechanical and magnetic properties. It was prepared by calcining iron oxide and alumina in the presence of molybdenum and its physical properties were investigated. Three different compositions of Fe₂O₃ and alumina Al(OH)₃ namely 1:1, 2:1, and 1:2 of Fe₂O₃:Al₂O₃ were also prepared. The matrix consists of two unsaturated polyesters (modified and unmodified). The modified one was synthesized by the reaction of carboxyl-terminated unsaturated polyester with (polyethylene glycol) of molecular weight 400 g mol⁻¹ to increase the solution behavior (solubility) in styrene. They were characterized by the IR, NMR spectrum, DSC, and GPC. The results obtained showed that, the prepared pigment compositions had moderate values of oil absorption, specific gravity, and bulking values and their pH concentration was in the alkaline range.

The mechanical strength and also the magnetic properties of the prepared composite samples increases with increasing Fe₂O₃ content in the pigment (Fe₂O₃:Al₂O₃). It was observed that addition of this pigment to the modified and unmodified styrenated polyesters converted the diamagnetic styrenated polyester to weak ferromagnetic composites at 1.6 T external applied field with different magnetic properties.

Keywords:

• Composites
• Fillers
• Magnetic properties
• Mechanical properties
• Modified polyester
• Pigments