Abstract
Despite advancements in digital technology, outdoor advertising remains one of the most effective advertising methods, and flexible vinyl banners are widely used for this purpose due to their good resistance to environmental factors and wind, high printing quality, and ease of use. Poly (vinyl chloride) or PVC, which is the third most widely used polymer in the world, serves as the primary material for flexible vinyl banners. These banners are mainly composed of PVC coating, polyester fabric, calcium carbonate, plasticizers and various additives. Unfortunately, these banners may pose significant health and environmental hazards to both humans and animals due to the release of hazardous chemicals such as chlorine, hydrochloric acid, phthalates, dioxins, dyes, and printing inks (including toluene, isopropyl alcohol). Traditional methods of incineration and landfilling are also not effective ways to dispose of vinyl banners because they release dangerous toxic gases and pollute the soil and landfill environment. Thus, recycling vinyl banners is challenging because PVC is bonded to another polymer such as polyester. The research suggests that mechanical recycling is the most efficient method for recycling PVC polymer-based products. With this goal, it is possible to make recycled products with higher added value, such as bags, luggage, flooring, mats, and wood-plastic composites. This article aims to provide a comprehensive review of flexible vinyl banners, including their introduction, chemical composition, manufacturing methods, environmental impacts, recycling and reuse methods.
Abstract
Despite advancements in digital technology, outdoor advertising remains one of the most effective advertising methods, and flexible vinyl banners are widely used for this purpose due to their good resistance to environmental factors and wind, high printing quality, and ease of use. Poly (vinyl chloride) or PVC, which is the third most widely used polymer in the world, serves as the primary material for flexible vinyl banners. These banners are mainly composed of PVC coating, polyester fabric, calcium carbonate, plasticizers and various additives. Unfortunately, these banners may pose significant health and environmental hazards to both humans and animals due to the release of hazardous chemicals such as chlorine, hydrochloric acid, phthalates, dioxins, dyes, and printing inks (including toluene, isopropyl alcohol). Traditional methods of incineration and landfilling are also not effective ways to dispose of vinyl banners because they release dangerous toxic gases and pollute the soil and landfill environment. Thus, recycling vinyl banners is challenging because PVC is bonded to another polymer such as polyester. The research suggests that mechanical recycling is the most efficient method for recycling PVC polymer-based products. With this goal, it is possible to make recycled products with higher added value, such as bags, luggage, flooring, mats, and wood-plastic composites. This article aims to provide a comprehensive review of flexible vinyl banners, including their introduction, chemical composition, manufacturing methods, environmental impacts, recycling and reuse methods.
EXTENDED ABSTRACT

Introduction

Vinyl flexible banners (VFB) that are made of polyvinyl chloride (PVC) are widely used for outdoor advertising because they can display clear images and graphics along with vibrant colors. Also, they are resistant to water, fungus, fire, UV, and freezing weather. Consequently, they are commonly employed to fabricate large-scale outdoor advertising signs, truck covers, and flags. PVC, which is the third most widely used polymer in the world, is the main material used to make vinyl flexible banners. These banners are mostly made of a PVC coating, polyester fabric, calcium carbonate, plasticizers, and other additives. Generally, three methods are used to produce advertising banners: the sticking process, the scraping process, and the calendering process. However, VFB is considered to be one of the most challenging materials in terms of environmental impact.

Environmental impacts
PVC stands out among prevalent polymers due to its significant incorporation of additives, including plasticizers and fillers. These additives have the potential to produce hazardous compounds when they interact with water and soil, thereby contributing to the contamination of groundwater resources. The presence of chlorine in polyvinyl chloride (PVC) contributes to the generation of dioxins and various other chlorinated organic compounds, which are subsequently emitted into the environment. The World Health Organization has indicated that dioxins resulting from the incineration or disposal of PVC waste pose significant risks to environmental integrity and the health of living organisms, categorizing these substances as carcinogenic. Phthalates are recognized as environmental contaminants utilized as plasticizers in banners. Research indicates that phthalates interfere with the human endocrine system, leading to issues like decreased sperm quality and infertility, respiratory illnesses, type 2 diabetes, and breast cancer, among others. The emission of widely used solvents in printing, such as isopropyl alcohol and toluene, along with chemical pigments, poses a potential threat to human health.

Recycling and reuse
The recycling of vinyl banners presents significant challenges due to their complex chemical composition, inks, and various materials present on their surfaces. When incinerated, PVC emits hazardous gases, including persistent organic pollutants like dioxins and furans. Additionally, the prolonged disposal of PVC waste in landfills poses risks of explosions and fires resulting from gas leaks, which can lead to considerable environmental harm over time. Given these environmental concerns, methods such as incineration and pyrolysis appear to be illogical.
Mechanical recycling represents the most effective approach for the recycling of VFB. This process involves the shredding of used VFB into smaller pieces, which are primarily used as fillers. The resulting materials can be repurposed for a variety of applications, including tarpaulins, roofing materials, vehicle covers, food grain storage, bags, and mats. Furthermore, these recycled materials can find use in products such as shoe soles, geotextiles, ropes, and pipes. An additional area of potential exploration is the development of wood-plastic composites derived from discarded vinyl banners; a topic that remains under-researched. PVC banners also serve as valuable components in the construction sector. In this context, studies have been undertaken to enhance or alter the properties of concrete by incorporating post-consumer vinyl banners, yielding relatively promising and noteworthy results. The inclusion of PVCFB in the concrete mix has resulted in a reduction in the water absorption of the concrete materials. Concurrently, a trend indicating a decrease in the compressive strength of concrete materials with the addition of PVCFB has also been observed.

Conclusion
VFB are very widely utilized tools in advertising and information matters, and their use is increasing steadily due to their suitable features. Since the chemical composition of them consists of various additives and plasticizers such as phthalates, they can cause irreparable harm to health and the environment. Traditional waste disposal methods such as incineration and landfilling are not effective methods for recycling and disposal of PVC due to the creation of high amounts of chlorine, the production of hydrochloric acid, the emission of dioxins and other hazardous organic compounds. Accordingly, the most efficient method of recycling PVC flexible banners is mechanical recycling, which involves crushing, melting and reshaping to produce the desired parts. Another application of waste banners is use in the construction industry, especially concrete.