Preparation of unsaturated polyester resin from polyester fabric scraps

Polyester and polyester blended cotton fabrics were chemically recycled by glycolysis. The reactions were carried out in propylene glycol with the presence of zinc acetate catalyst at 0.5% and 1% by weight of the fabric at 180 ํC under reflux in nitrogen atmosphere. The reaction time was varied at 4, 6 and 8 hours. The glycolyzed products were then esterified using maleic anhydride in order to obtain unsaturated polyester resins. The prepared resins were cured using styrene monomer, methyl ethyl ketone peroxide (MEKPO) and cobalt octoate as a crosslinking agent, an initiator and an accelerator, respectively. The mechanical properties and thermal stability of the products prepared under different conditions were studied. The experimental results indicated that the products from resin prepared under 8-hour glycolysis possessed highest mechanical properties, i.e. hardness, flexural strength and impact strength. The thermal stability was found to be depended on glycolysis time. The products from resin prepared under 8-hour glycolysis exhibited the highest thermal stability. However, the mechanical properties of products from the glycolyzed resins were lower than those of commercial resin. This polyester fabric based resin offers a new class of unsaturated polyester resin that can be fabricated into products by the conventional casting method