By adding the biodegradable additive EPI to the raw materials of films and bags, the degradation and decomposition of plastics in nature is accelerated. TAPA manipulates the life-span of PP, PE and PS when added to them, making them exhibit signs of degradation when exposed to ultraviolet light (sunlight) and high heat, mechanical stress and microorganisms in the soil. The useful life of biodegradable plastics containing EPI can be changed from several months to several years depending on the type and amount of EPI added.