Future of Vinyl Banners: Chemical Composition, Toxicity, Environmental Impact and Degradation

Abstract

Poly vinyl chloride (PVC) is a thermoplastic of about 800-1500 monomer units long. Due to its low cost, desirable properties and versatility, PVC can be processed into a wide range of short-life products. As a result of increasing consumption of PVC-made products, the quantity of used PVC items entering the waste stream is gradually increased. One application of PVC is as either a thin or thick coating for flexible polyester advertising banners. PVC-coated banners are particularly challenging for recycling, as the PVC is bonded to another polymer, usually polyester. The whole life cycle of polyvinyl chloride banner industry releases a lot of solid wastes, air wastes, water wastes and other environmental toxins. Cross-linking, thermooxidative degradation of polymer and plasticizers, polymer dehydrochlorination, and diffusional desorption of a plasticizer occurs in aged PVC materials. Biodegradation of PVC leads to reduction of polymer molecular weight due to the shortening of the polymer chains and elimination of their fragments. Microorganisms are capable of degrading inorganic and organic materials, and interest has been aroused to study microbes for their ability to degrade synthetic polymers. The replacement of slowly degradable materials with biodegradable materials is other ecological alternative addressing the problem of waste surging in the environment caused by vinyl banners.