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Forget the Leather, Faux is Better Life Cycle Analysis of PVC-based Faux Leather Vince Jethro Alba, Maria Larisse Hernandez, Nathaniel Latoza, Bianca Regina Sia, Kendric Aaron Tee Depatment of Environmental Science School of Science and Engineering Ateneo de Manila University Introduction Leather, a luxurious material used in many industries such as fashion and furniture, has always been in demand due to the durability, quality, and the aesthetic of the material, However, there are growing concerns on its high price as well as its environmental impact. Because of this, there was a need to find a cheaper and more environmentally responsible alternative, resulting in the creation of faux leather. Faux leather, also called leatherette, fake, artificial, synthetic, or vegan leather, is a material manufactured to imitate cured animal hide. The first example of the creation and production of faux leather was in 1839 when Charles Goodyear created what he perceived as “vegetable leather” which was used for automobile tires. It was in the 1920’s when the first form of the modern faux leather was created. This new leather was now created using polyvinyl chloride (PVC) but was criticized for its “fake” quality, so improvements were done throughout the years to create a more authentic leather quality. Today, there are two kinds of faux leather based on the production of the material: polyurethane and PVC upholstery. Polyurethane leather is made by coating fabric material with polymer while PVC leather is made of a layer of polyester fiber that is coated with vinyl. There are other forms of faux leather created with different other materials such as pineapple leather although these have not yet been as mass produced as polyurethane and PVC leathers. Faux leather, compared to genuine leather has been found to cost less to produce and is convenient in production due to its consistent appearance and its flexibility, making it easy to work with. As for the material itself, good quality faux leather is known to be durable, waterproof, and low maintenance. Faux leather is also deemed animal friendly because, unlike its counterpart, the material used in faux leather does not require the hide of an animal but is created using chemical compounds such as the polyurethane or polyvinyl chloride to protect the base fabric material, plasticizers and lubricants to make the material soft and flexible, as well as dyes to change the appearance of the material. PVC, the more commonly used material in creating faux leather, is an odorless and solid thermoplastic that is created by replacing H ions within a vinyl group with chlorine. As a mass produced product, a life cycle analysis (LCA) must be performed in order to study and quantify the possible environmental impacts that arise from the product. An LCA examines all inputs (raw materials, resources, etc.) involved, outputs (products, byproducts, wastes, etc.) produced, and the processes in manufacturing to assess how a product can affect the environment. The stages of an LCA include: (1) An inventory analysis wherein all the inputs and outputs of a single product’s life cycle are accounted for such as all the raw materials needed to create it and the wastes produced after the consumption of the product. (2) An impact analysis is performed to describe the possible effects of the

product in each of its life stages to the environment. (3) And lastly an improvement analysis which seeks areas in production wherein changes may be implemented to reduce any environmental impacts. An LCA provides a concrete and quantitative analysis to easily measure any environmental impacts that may arise from the life of the product in order to stay within any regulatory environmental expectations. The stage by stage analysis of an LCA makes it possible to identify which points in the product life cycle need improvement. In this study, an LCA will be conducted in the manufacturing of faux leather in order to evaluate the environmental impacts that may arise from the material’s production. The LCA will go over the inputs and outputs of the extraction of raw materials, production, distribution, consumption, and disposal stages of the life cycle of faux leather products in order to assess the benefits and drawbacks of producing and consuming faux leather as well as finding possible areas for improvement in the manufacturing process. The study is limited mostly to PVC-based faux leather products. Due to the unavailability of data, only a qualitative life cycle analysis was conducted, and other sources are not extensively researched.

Life Cycle Inventory

Discussion Extraction The main raw material involved in making faux leather is crude oil, which is extracted from oil reserves underground and underwater. The processes involved in extracting crude oil and refining it for various purposes have several impacts. Crude oil extraction and refining releases various air pollutants such as volatile organic compounds (VOCs) such as benzene, toluene, ethylbenzene, and xylene (BTEX) compounds, particulate matter (PM), nitrogen oxides (NOx), hydrogen sulfide H2S), carbon dioxide (CO2), carbon monoxide (CO), and sulfur dioxide (SO2) (US EPA, 2003), all of which are related to various health and environmental problems. Wastewater effluent is another major source of pollution from oil refineries (US EPA, 2003). This may contain several hazardous substances including various hydrocarbons such as polycyclic aromatic hydrocarbons (PAHs) and ammonia (Wake, 2004). In addition to these impacts, crude oil extraction and refining needs substantial amounts of water for cooling, using around 1-2.5 gallons of water per gallon of oil (US EPA, 2016), and consumes a lot of energy due to the temperatures (up to 600℃) required for fractional distillation (Freundrich, 2001). Production Production includes three main steps: production of PVC, production of the leatherette itself, and production of the finished leatherette product. As shown in Figure 2, production of polyvinyl chloride begins with reacting ethylene and chlorine to produce ethylene dichloride (EDC). EDC undergoes thermal decomposition to produce vinyl chloride. Polymerisation follows to in turn form PVC. PVC production inputs include energy, water, the extracted crude oil, and salt (NaCl). By-products of the produced PVC involve a number of chemicals that are known to be toxic to the environment, among which are sulfur dioxide, trace amounts of dioxins, hydrochloric acid, volatile organic compounds or VOCs, and sodium hydroxide. PVC production uses approximately 40% of the total chlorine production, or 16 million tons of chlorine per year on a global scale. It is also the only major building material that is organochlorine, posing severe hazards to environmental and human health, through its by-products (Thornton, 2002). Dioxins, for instance, are considered one of the most toxic man-made poisons. Dioxins bioaccumulate, making them stay in the human body for incredibly long periods of time, thus also making their effects harder to treat (Bloch, 2007). There is no known safe dose of dioxins, which means that even the smallest dose can contribute to damages in the human body. Moreover, it is a potent carcinogen. Vinyl is one of its main sources, and thus, PVCs will always have dioxins as one of its several by-products (Thornton, 2002). However, more modern facilities are able to reduce dioxin emissions up to a point where the risk is considered negligible (Baitz et al., 2004).

Figure 2: Production phase (Adapted from Baitz et al., 2004) A significant amount of energy and steam power is used to produce leatherette from its PVC base. Among the raw materials used to produce leatherette are phthalates, acetone, sunthene 410, Pliovac Resin M70, Calcium carbonate, plasticized pigments, DOP, VS10, DMF, Mek, Blowing ration mixture, and viscosity (Andrews and Cogdell, 2013). Plasticizers, stabilizers, and fillers are added to further enhance the quality of leatherette (Burns, 2013). Common plasticizers for PVCs include phthalates, which aid in making the product more durable as PVC on its own is brittle. These phthalates however, are also persistent under some conditions, thus resisting natural degredation. They also bioaccumulate, posing threats to the environment, especially considering that massive amounts of these chemicals are released into the environment each year from vinyl production. In fact, they leach out of vinyl products as well, since they are simply mixed with the polymer during formation. Phthalates are known to have caused problems in reproduction and development (Thornton, 2002). The stabilizers used are mostly made up of lead and other heavy metals such as cadmium and organotins. They are also considered highly toxic materials which do not degrade in the environment, contributing to damages in the brain and in the immune system, also occasionally leading to cancer in significantly high amounts, particularly of cadmium (Thornton, 2002). The production of leatherette materials such as bags, wallets, covers, and the like is not as energy intensive as the production of the leatherette itself because these materials can often be made by hand using cutters and bonding agents. In most cases, consumption of energy occurs during transportation of the raw materials and the use of sewing machines.

Distribution After the product has been manufactured, the next step is to get the bags, shoes, covers, and clothes out to the consumers. A lot of the processes involved here are packaging methods and ways of delivering leatherette. After creating the leatherette products, movement to different stores, outlets, and consumers is done through vehicles, which consume fuel, contributing to the rising levels of greenhouse emissions. Research on the effects of the by-products of fossil fuel emissions showed that the most common pollutants emitted by a motor vehicle include CO, CO2, NOx, HC, SO2, lead (Pb), and suspended particulate matter (SPM), which are all toxic to humans and can lead to environmental degredation (Amarachi, 2016). Fuels such as gasoline and diesel are not the only input being used for distribution of leatherette. The packaging material used must also be included, and this can either be paper, plastic, or wood. Paper packaging materials are easy to analyze; coming in bags or boxes, they can be manufactured from recycled paper or from raw materials and can take up almost the same amount of space as plastic bags. Plastics are created synthetically, as explained in the previous sections, by combining different chemicals and going through elaborate processes to create plastics specific to different kinds of uses. Plastic packaging is more durable than paper but is harder to dispose of and tends to accumulate in the natural environment. These first two methods of packaging are significantly better than wooden materials when it comes to distribution. There are two things to consider when transporting goods: weight and space occupied by the goods. With plastic and paper, more products can be brought in a single trip, assuming that the products themselves do not need extreme care when it comes to handling. Wooden crates, on the other hand, have fixed dimensions and present a limit to the number of products that can be transported, since not all the crates would fit in a single trailer or van (Sauer, 2004). Overall, manufacturing these packaging materials all lead to pollution, what singles them out is the efficiency that each method can bring, which could lead to reduced use of the packaging and reduced need for production. Consumption This refers to the use of the leatherette by consumers. Even in the act of purchasing a leatherette product, resources are being used. Gasoline or diesel is used by the consumer in his or her commute to purchase the faux leather products, leading to emissions that could contain various pollutants explained earlier in the distribution section. Aside from this, maintenance of the product should also be considered. Faux leather or leatherette, just like other leather products, is susceptible to cracking if not reinforced with natural fibers (such as cotton) and must be given the right amount of care. Leather conditioners and special oils are able to soften the product and prevent it from cracking in high temperatures and intense sunlight (Chateigner, 2013). Disposal The process of leatherette disposal involves two main steps, namely, waste preparation and recycling or disposal. For preparation, PVC wastes are collected and separated according to how they will be processed afterwards. With auxiliary materials added, the segragated wastes can undergo mechanical recycling, which produces fillers, materials that increase stiffness and temperature resilience; chemical recycling, wherein certain chemicals such as chlorinated by-products or hydrochloric acid from PVC production are reacted with other chemicals (e.g. ethylene) to once again produce EDC; waste

incineration resulting in power and/or steam as its output; and lastly, either from the separated wastes or wastes from after the recycling or incineration processes, is disposal into landfills, which contributes to air and water pollution. These emissions include chemicals such as phthalates, CO2, NOx, CO, hydrocarbons, organotins, particulate matter, SO2, methane and other landfill gases, and other toxic wastes (Baitz et al, 2004). There are a variety of ways to recycle faux leather products. EVC can be reused, for instance. However, not much of the post-consumer waste can be recycled, making this one of the drawbacks of using PVC products. Pre-consumer wastes on the other hand, could be “collected separately in defined quantities, and hence has a recycling rate in practice” (Baitz et al, 2004). Incineration reduces waste masses, but also unfortunately contributes to environmental hazards, but this is offset through the use of modern incineration facilities which implement more stringent pollution controls (Baitz et al., 2004; Comission of the European Communities, 2000).

Figure 3: Disposal Phase (Adapted from Baitz et al., 2004)

Polyurethane as an alternative to PVC Aside from PVC, another material that can be used in the production of synthetic leather is polyurethane. It is a versatile material that can be made flexible or rigid and can be used in a variety of applications such as insulation, cushioning for furnitures, coating, shoes sole, sportswear, and many others. Similar to PVC, polyurethane is also a polymer composed of organic units. Moreover, it also uses several chemicals in its production such as isocyanates, polyester polyols, nitric acid, sulphuric acid, benzene, glycols, and other additives (Lee, 2002). Among the two synthethic leather materials, however, polyurethane is considered to be more environmentally friendly as it does not produce as much dioxin as

PVCs making it far less toxic (Koerner, 2007) and does not need plasticizers (Kinge et al., 2013). In addition, polyurethane-based synthetic leather is regarded to be a more realistic imitation of genuine leather with respect to surface feel and overall appearance (Blesius, 2014). Polyurethane-based synthetic leatherette materials also have their own flaws. Since polyurethane is made from petroleum, a non-renewable resource, its production may not be sustainable in the long run (Kirschner et al., 2014). Moreover, making this material contributes greatly to global warming and climate change as it emits 3.7 pounds of CO 2 for every pound of polyurethane foam (Koerner, 2007). Although polyurethaneis considered to be biodegradable, it will take approximately 500 years for the material to completely degrade in nature. Areas for improvement As one of the oldest plastic material known to man, PVC has evolved drastically throughout the years. The rapid advancements in technology have continually improved the production of PVC and PVC materials to address several economic, social, and environmental concerns. However, despite the progress, it is with no doubt that much work still needs to be undertaken. The following are a list of recommendations to further improve production of PVC and PVC-based materials: ●

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Research on the viability of polycarbonate diol (PCD) or similar substances for use in PVC leatherette production to improve its overall strength and durability. Polycarbonate diols, which are being incorparted in polyurethane production in recent yaers, provides extreme durability to heat, chemical and hydrolytic imbalances, and abrasions. It is also determined to increase flexibility of polyurethane leatherettes (Kasei, n.d.). Application of plasma treatment in PVC leatherette production to improve its resistance to staining. Plasma treatment under atmospheric pressure, as one study shows, is capable of increasing liquid repellency in synthethic leather (KWong and Kan, 2015). Research on the viability of energy and water consumption reduction in the production of PVC leatherette and leatherette materials where economically and ecologically warranted. Continue to research and develop new alternatives to common PVC stabilizers, such as lead, which are harmful to health and the environment. Research on the viability of recycled oil as an alternative to crude oil to make production of PVC leatherette and leatherette materials more sustainable. Stricter implementation of quality standards of leatherette material manufacturers to prolong the end product's shelf life thus avoiding the build-up of PVC wastes in landfills.

Conclusion Faux leather or synthetic leather is now highly in demand in lieu of real leather. While many consider it to be more eco-friendly than real leather, there remains a number of environmental and health impacts from the extraction, production, distribution, consumption,

and disposal of this material. Several hazardous chemicals are emitted into the environment in each stage, especially with the use of PVC-based faux leather. Disposal is also a huge issue that leatherette producers face since PVC is nonbiodegradable, and while some substances can be reused, most of it cannot be recycled, thus contributing further to pollution. With this in mind, several alternatives for the base material for faux leather are already in use. Polyurethane synthetic leather, for instance, is becoming more popular, as it is considered more eco-friendly than PVC. Other alternatives include “vegan leather” or vegetable-based leather, which can be made of pineapple, cork, kelp, among others.Aside from this, other steps can be undertaken in order to reduce the overall impact of faux leather throughout its life cycle such as finding alternative raw materials like bio-ethanol or recycled material, stricter implementation of manufacturing quality standards, use of less toxic additives, and improvements in waste treatment and disposal methods, among others. Such improvements will go a long way in making faux leather an environmentally friendly material for use in a plethora of products. References Andrews, T. Cogdell. 2013. Synthetic Leather: The Real Cost of Fake Leather (Wastes and Emissions). Web. 30 Nov 2016. Retrieved from http://www.designlife-cycle.com/syntheticleather/ Baitz, M., Kreißig, J., Byrne, E., Makishi, C., Kupfer, T., Frees, N., Bey, N., Hansen, M.S., Hansen, A., Bosch, T., Borghi, V., Watson, J., and Miranda, M. 2004. Life cycle assessment of PVC and of principal competing materials. European Commission. Blesius, Jim. 2014. What is Faux Leather?. Web. 01 Dec 2016. Retrieved from: http://mitchellfauxleathers.com/Default/ViewPoint/Read/faux-leatherviewpoint/2014/04/07/what-is-faux-leather Burns, A. 2013. Life Cycle of Synthetic Leather and Raw Materials. Design Life-Cycle. Web. 01 Dec 2016. Retrieved from http://www.designlife-cycle.com/synthetic-leather/ Chateigner, Jean-Marc. “How to prevent faux leather from cracking?”. 7 January 2013. Web.30 November, 2016. Retrieved from http://fauxleatherguide.com/how-to-prevent-fauxleather-from-cracking.html Commission of the European Communities. (2000) “Green paper: Environmental issues of PVC.” Brussels, Belgium. Faux Real. PU and PVC Leather. 14 May 2010. Web. 30 Nov 2016. Retrieved from: http://pu-leather.net/ Freundrich, Craig. How oil refining works. 4 January 2001. HowStuffWorks.com. Retrieved http://science.howstuffworks.com/environmental/energy/oil-refining.htm

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How do faux leather fabrics compare to real leather? Garrett Leather Corp. 25 Apr 2016. Web. 30 Nov 2016. Retrieved from: http://www.garrettleather.com/blog/how-do-faux-leatherfabrics-compare-to-real-leather/ Jim Blesius. What is Faux Leather? Mitchell. 7 Apr 2014. Web. 30 Nov 2016. Retrieved from: http://mitchellfauxleathers.com/Default/ViewPoint/Read/faux-leatherviewpoint/2014/04/07/what-is-faux-leather Jim Blesius. Polyvinyl Chloride - Vinyl Synthetic Leather. Mitchell. 4 Dec 2014. Web. 1 Dec 2016. Retrieved from: http://mitchellfauxleathers.com/Default/ViewPoint/Read/faux-leatherviewpoint/2014/12/04/polyvinyl-chloride---vinyl-synthetic-leather Kasei, Asahi. nd. Polycarbonate diol: Use in leather applications. Web. 01 Dec 2016. Retreived from: https://www.asahi-kasei.co.jp/pcdlhp/en/hikaku.html Kinge, A.P., Landage, S.M., and Wasif, A.I. .2013. Nonwoven for artificial leather. International Journal of Advanced Research in Engineering and Applied Sciences 2(2): 1833. Kwong and Kan. 2015. Improvement on stain resistance of synthetic leather by plasma treatment under atmospheric pressure. Web. 01 Dec 2016. http://ira.lib.polyu.edu.hk/handle/10397/40911 Lee, Steve. 2002. The Polyurethanes Book. Ed. David Randall. N.p.: Huntsman International LLC. Life Cycle Analysis. The Environmental Literacy Council. 2015. Web. 30 Nov 2016. Retrieved from: https://enviroliteracy.org/environment-society/life-cycle-analysis/ Negha Cherian. This vegan leather is made from a truly sustainable source: pinapples. Global Citizen. 16 May 2016. Web. 30 Nov 2016. Retrieved from: https://www.globalcitizen.org/en/content/sustainable-vegan-leather-made-from-pineapples/ Nkwoada Amarachi, Oguzie Emeka, Alisa Christopher, Agwaramgbo Lovell, Enenebeaku Conrad. “Emissions of Gasoline Combustion by Products in Automotive Exhausts”. Published at: International Journal of Scientific and Research Publications (IJSRP), Volume 6, Issue 4, April 2016 Edition. Retrieved from http://www.ijsrp.org/research-paper0416.php?rp=P525289#citation Sauer, Beverly J., Franklin Associates. “Life Cycle Inventory of packaging options for shipment of Retail Mail-Order Soft Goods: Final Peer Reviewed Report”. 9 June 2004. Web. 28 Nov 2016. Retrieved from http://www.deq.state.or.us/lq/pubs/docs/sw/packaging/LifeCycleInventory.pdf The Charles Goodyear Story Goodyear Corporate. n.d. Web. 30 Nov 2016. Retrieved from: https://corporate.goodyear.com/en-US/about/history/charles-goodyear-story.html

Thornton, J. 2002. Environmental Impacts of Polyvinyl Chloride (PVC) Building Materials. Web. 30 Non 2016. Retrieved from http://www.pulpworksinc.com/environmental-impacts-ofpvc.html Wake, H. (2005) Oil refineries: A review of their ecological impacts on the aquatic environment. Estuarine, Coastal and Shelf Science (62): 131-140. Who does LCA & Why? Athena Sustainable Materials Institute. n.d. Web. 30 Nov 2016. Retrieved from: http://www.athenasmi.org/resources/about-lca/who-does-lca-why/