Design Life-Cycle

 Jessica Munguia

Professor Christina Cogdell

DES40A

04 December 2019

Raw Materials of Lululemon Yoga Mats 

Lululemon yoga mats are used to exercise one’s mind, body, and environmentally friendly practices. Lululemon’s mission statement is to create positive change for a healthier and thriving future. This mantra is expressed in the life cycle of the yoga mat. Lululemon yoga mats are composed of polyurethane, polyester, nylon and natural rubber; with the addition of an antimicrobial agent made out of silver nanoparticles. Throughout the different stages of the yoga mat life cycle, Lululemon has implemented policies, such as the Dodd Frank Act and partnered with the Forest Stewardship Council to use eco- friendly materials. In addition, to ensure the integrity of the sources from which Lululemon extracts raw materials, the company also has a collaboration with the not- for- profit organization, Canopy, and created a partnership with Australian Packaging Covenant Organization to create the Box Reuse Program and the Sustainable Product Packaging Policy to reduce waste in efforts for zero- waste packaging and product design. At the end of the yoga mats’ life cycle all  old or unwanted yoga mats are recycled into equestrian footing. 

Lululemon yoga mats are made of about five raw materials. The first ingredient to make the yoga mat is polyurethane. This material is a synthetic polymer, formed by reacting a polyol, which is “an alcohol with more than two reactive hydroxyl groups per molecule,” with a diisocyanate (“Polyurethane”). Due to the wide variety of polyols and diisocyanate, there are many different shapes this reaction can produce, but to make the yoga mat the polyurethane needs to take the form of a flexible foam (“Polyurethane”). The next two materials that make up the mat are polyester and nylon. Polyester and nylon are also both synthetic fibers. Polyester is derived from coal, air, water and petroleum. The polyester fibers are formed through a chemical reaction between an acid and an alcohol. These fibers are very long, strong, and stable (“Polyester”). Nylon is made from organic compounds found in coal or petroleum. The nylon polymer is formed by a thermal reaction between adipic acid and hexamethylenediamine with the addition of pressure. Once the molecules are fused together, a chemical reaction called condensation polymerization occurs, creating nylon (Woodford et al., 2019). These materials are then combined to allow the mat to absorb moisture and is able to be wiped clean of any sweat or dirt left on the mat after a workout. All of these raw materials are nonrenewable, since they are derived from petroleum; however natural rubber and latex are renewable (Muthu et al., 2012). The raw materials are latex and natural rubber. Natural rubber and latex are extracted from the Heva Brasiliensis, commonly known as the Amazon rubber tree, by making an incision on the tree bark and collecting the milky white latex that is excreted from the tree. The composition of the latex depends on the season and the age of the tree. When the latex coagulates, it is then transformed into natural rubber (Ferreira et al., 2009). However, the yoga mat is not just made of natural rubber, there is also the addition of synthetic rubber. Synthetic rubber is another polymer-plastic,  made up of a combination of cis-isoprene units and trans-isoprene units (Bode et al., 2001). The rubber and latex materials are placed on the bottom of the mat, for the addition of grip and cushioning. Lastly, an antimicrobial agent, made up of silver nanoparticles, are synthesized and deposited onto the yoga mat in order to fight bacteria and prevent mold and mildew (Perelshtein et al., 2008) (“The Reversible Mat 5mm”). Even though most of these raw materials are nonrenewable, Lululemon has done their best by implementing partnerships and policies that demand sustainable sourcing of the raw materials. 

In order to follow the company’s promise for sustainability, Lululemon has partnered with the Forest Stewardship Council and Canopy; in addition to following the strict guidelines of the Dodd- Frank Act, to ensure the sourcing of their raw materials are done ethically and responsibly. Lululemon has a partnership with the Forest Stewardship Council, in order to use FSC- Certified natural rubber for the yoga mat, as well as other paper materials (“New FSC-Certified Products”). This ensures the use of sustainable forest management practices, when it comes to extracting raw materials from trees. In addition to the FSC for sustainable forest management practices, Lululemon also works with Canopy, a not- for- profit organization that helps companies develop business solutions that protect forests and guide them to better purchasing practices (“For the Love of Forests”).   When it comes to metals, Lululemon is in compliance with the Dodd- Frank Act, which ensures functional metals do not consist of tin, tantalum, tungsten or gold (3TG). The Dodd- Frank Act also makes suppliers sign a certificate of acknowledgement, agreement, and declaration that the metals and materials sourced do not come from the Democratic Republic of Congo or any surrounding countries; in order to maintain an ethical practice for sourcing raw materials (“Metals + Materials”). Production is not the only place where Lululemon uses the power of partnership to make sustainable choices, they also make sure their code of ethics apply in the packaging department.

Lululemon also has a partnership with the Austrailian Packaging Covenant Organization which assists the company in creating the Box Reuse Program and Sustainable Product Packaging Policy to make conscious decisions for packaging. When packaging the yoga mats the raw materials used would be paper and glue, to create the cardboard boxes that the yoga mats are placed in for transport and soft plastics for extra support during shipping. The Austrailian Packaging Covenant Organization (APCO) has aided Lululemon in trying to reduce their waste and recycle their product packaging and distributing materials. This organization has worked out an action plan with Lululemon that follows the “APCO Packaging Sustainability Framework” which gives the company guidelines for assessing packaging sustainability (Austrailian Packaging Covenant Organization, 2018). There is also an annual report made to show the company’s successes and future goals towards zero- waste packaging and design. In the annual report for 2018, APCO stated that Lululemon has achieved Level 4: Leading, meaning that the company “has more rigorous procedures in place, or an ambitious target has been met” (Austrailian Packaging Covenant Organization, 2018). One of the rigorous procedures put in place is the Box Reuse Program. This program reused 78% of all boxes for outbound shipments (Austrailian Packaging Covenant Organization, 2018). Lululemon has also made a statement that, “more than 1 million boxes are saved each year” (“Packaging & Waste”). Another way Lululemon has practiced eco-friendly packaging is by implementing the Sustainable Product Packaging Policy, this ensures their product is fully recyclable at the end of the life cycle (“Packaging & Waste”). This program has allowed the company to reuse and recycle “more than 90%  of materials (soft plastics and corrugate used in transportation)” (“Packaging & Waste”). There is a great deal of recycling done in the packaging phase of the life cycle, and the recycling continues to the last stage of a yoga mats’ life.

Lululemon recycles their yoga mats into equestrian footing through an alliance with Reiten Right. Even though some of the raw materials in which the yoga mat is composed of  are nonrenewable and can be difficult to recycle, Lululemon has figured out a way in which to make recycling their yoga mats possible. The company has made this possible through another partnership, with a company called Reiten Right. This company is a premium supplier for equestrian footing, an accessory that recycles Lululemon yoga mats (“Packaging and Waste”). Equestrian footing is an extra dressing for previously placed on top sand footing that is dispersed over the equestrian arena floor. This provides competing horses with more balance and cushioning. The yoga mats are cut up into tiny pieces that mimic tan- bark, and then transported in large totes (“The Best Arena…”). Even though it seems as if Lululemon has done their best to follow their morals in creating a closed circle life cycle, there are some parts of the yoga mat life cycle that are unclear.

Lululemon has plenty of claims on their website about how sustainable they are with their sourcing of raw materials; however, some of these statements are just greenwashing. One of the first misconceptions are FSC- Certified natural rubber in the yoga mat. When investigating Lululemon’s partnership with the Forest Stewardship Council, they do in fact use FSC- Certified materials; however when looking at the description for all of the different types of yoga mats Lululemon sells, only the Carry Onwards Mat stated that it was made with FSC-Certified natural rubber. The other styles just say they are compounded of natural rubber, synthetic rubber and polyurethane. Another deceiving detail is the percentage of natural rubber. All of the different styles of yoga mats are not made purely from natural rubber, there is at least 17% of synthetic rubbers in the mats, and in the Carry Onwards Mat there is more synthetic rubber than there is natural rubber (“The Reversible Mat 5mm”). One other aspect of the yoga mat life cycle that proves difficult to uncover is just how Lululemon collects the unwanted yoga mats for recycling. The company says they recycle all unwanted and damaged yoga mats into equestrian footing, but there is no information on how customers can return or drop off their old and broken, unwanted mats. If the company only recycles mats at the distribution center, saying they recycle “all” the yoga mats is not true. This would be a good opportunity; however, for Lululemon, to create a bin in each store to put unwanted items for recycling. 

Lululemon yoga mats are only made up a few raw materials; however, their impact on the environment is much greater. In order to stay true to the company’s mantra, Lululemon has illustrated their dedication to creating zero- waste packaging and production of yoga mats. When it comes to sourcing the raw materials that make up yoga mat, Luluelemon has also implemented the Dodd- Frank Act, in order to ensure the integrity of the suppliers. The Dodd- Frank act gives an abundance of strict guidelines for the suppliers to follow in order to source the raw materials for the yoga mat in the most sustainable and ethical way as possible. Most suppliers are questioned and asked to sign certificates, in addition to other documents of acknowledgement that the raw materials being extracted are done ethically and sustainably. By partnering with the Austrailian Packaging Covenant Organization, Forest Stewardship Council, and Canopy Lululemon has made sustainable choices in the manufacturing and packaging part of the life cycle. These partnerships work with Lululemon to validate the company is following environmentally conscious to reduce waste and, in some cases, give back to the forests from which some of the raw materials for the yoga mats reside, to guarantee a sustainable process; in addition to starting a Box Reuse Program to reuse boxes in the packaging and distributing step, in order to reduce waste. Lululemon also uses a partnership with Reiten Right, to recycle the yoga mats at the end of their life cycle into equestrian footing; although, it is unclear if all yoga mats are made with FSC- Certified materials, and if anyone can recycle their yoga mat into horse competition floor grip. Overall, throughout the different stages of the yoga mat life cycle, Lululemon has put in a sufficient amount of effort to create a yoga mat with a closed life cycle. 

Bibliography

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Canopy works with companies to develop business solutions that protect forests. Canopy ensures large- scale forest transformation and conservation. They partner with brands to help each company come up with new purchasing practices as well as creating permanent solutions in order to not harm the endangered forests.

Austrailian Packaging Covenant Organization. 2018 Annual Report & Action Plan: Lululemon Athletica Australia Pty Ltd. Sydney, AU: APCO, 2018. https://www.packagingcovenant.org.au/documents/item/1807

This annual report goes more in detail on how Lululemon is actively trying to reduce their waste and recycle their product packaging and distributing materials. In 2017, the company downsized the hangtags saving 60% in material. FSC- certified materials is also used in some packaging. Lululemon states that they met with rubber suppliers at plantations to discuss their sustainable priorities. The company named the rubber they use, Luvea. 

Baalbaki, S., Gilliard, D. J., & Hoffman, D. L. (2019). Is Lululemon Athletica’s Turnabournd Sustainable?. American Journal of Management, 19(2). https://doi.org/10.33423/ajm.v19i2.2065

Lululemon relies on many manufacturing facilities and a limited amount of suppliers to extract the raw materials. The company does not rely on long-term contracts. Venders are selected carefully and go through different screening processes. Most of their products are produced in South East Asia; the rest are produced in South Asia, China, and North America.

Bode, Helge B., Kirsten Kerkhoff, and Dieter Jendrossek. "Bacterial degradation of natural and synthetic rubber." Biomacromolecules 2.1 (2001): 295-303.

Natural rubber is a biopolymer, in contrast to synthetic rubber which is a polymer mainly made up of cis- isoprene units in combination with trans- isoprene units. Depending on the polymerization the percentage of different units can vary. Synthetic rubber is still not as strong as natural rubber, so most of the time natural rubber still has to be present in products made of these materials. 

Woodford, Chris. “Nylon - The Science of Synthetic Textiles.” Explain That Stuff, 31 Jan. 2019, https://www.explainthatstuff.com/nylon.html.

Nylon made up of polyamides. This material is made from organic chemicals found in coal or petroleum. The nylon polymer is made by a thermal reaction between to large molecules; pressure is then added to fuse them together. Condensation polymerization then occurs and nylon is formed. 

Cox, Stacey, and Kristin Stephensen. “Extraction of Raw Materials.” Commodity Chain Project Lululemon Athletica, 2015, u.osu.edu/commoditychainlululemon/extraction-of-raw-materials/.

Lululemon follows strict guidelines for extracting their raw materials. They are a part of the Dodd Frank Act. This means that metals used in their products don’t contain tin, tantalum, tungsten, or gold. In addition, if they do contain any of these metals, they can’t come from the Democratic Republic of the Congo or any surrounding countries.

Dandapure, Yogendra V, and Katherine Douglas. Exercise Mat. 4 July 2013.

This is the patent for the yoga mat. The bottom layer is made up of natural rubber. The top layer is made of nanofiber, which is a mixture of polyester and nylon. The layers are bonded together using thermally. There is also an antimicrobial agent added, that is silver based. The logo is printed using silicone ink. 

Ferreira, Mariselma, et al. “Angiogenic Properties of Natural Rubber Latex Biomembranes and the Serum Fraction of Hevea Brasiliensis.” Brazilian Journal of Physics, vol. 39, no. 3, Sept. 2009, pp. 564–569., doi:10.1590/s0103-97332009000500010.

This journal provided information about natural rubber and latex, which makes up the bottom layer of the yoga mat. Natural rubber is derived from Heva Brasiliensis (Amazonian rubber tree). The makeup consists of 30- 45% weight of  rubber molecules, 4-5% weight of non-rubber molecules (protein, lipids, carbohydrates, sugar), and 50% water. The latex composition depends on the season the natural rubber is extracted and the age of the tree. 

“Fibre.” Forest Stewardship Council, fsc.org/en/page/fibre.

Fibre is the value chain which supplies the paper, with which the product hangtags are made from. FSC sources the pulp for production of the hangtags. They use sustainable forest management practices. This allows companies (Lululemon) to say they are sourcing responsibly. The FSC system secures long term source of paper. 

“For the Love of Forests.” Lululemon, 2019, info.lululemon.com/sustainability/responsible-supply-chain/raw-material-sources/protecting-ancient-forests.

Lululemon is based in Vancouver, British Columbia. The company states that they are committed to developing and using materials that support protection of forests. They have partnered with Canopy. Canopy is a not- for- profit environmental organization that plans to protect ancient and endangered forests through mindful fabric choices.

Leonas, Karen K. "The use of recycled fibers in fashion and home products." Textiles and Clothing Sustainability. Springer, Singapore, 2017. 55-77.

There are many ecological and social benefits to recycling polyester. The synthetic fibers are chemically recycled. Textile waste can be classified into three different categories, each of which have different recycling approaches. Polyester are broken down into chips, which are then decomposed, repolymerized, and spun into new polyester fibers. 

“Metals + Materials.” Lululemon, 2018, info.lululemon.com/sustainability/responsible-supply-chain/raw-material-sources/metals-minerals.

Lululemon states they use a limited amount of metals in product. They are in accordance with Dodd-Frank Act (Section 1502). The company works with their suppliers and expect them to purchase 3TG materials from sources not involved with the DRC. They go as far as making their suppliers sign a form of agreement, a certificate of acknowledgement, and a declaration of metals and materials. This is to ensure that all materials don’t come from the DRC or any surrounding countries.  

Muthu, Subramanian Senthilkannan, et al. "Quantification of environmental impact and ecological sustainability for textile fibres." Ecological Indicators 13.1 (2012): 66-74.

This article explained how sustainable different textile materials can be. Nylon and polyester are nonrenewable materials due to the fact that they come from petroleum. In contrast, rubber and latex are renewable because they come from a tree, which is a natural source. Nonrenewable materials are difficult to recycle and don’t biodegrade.

“New FSC-Certified Products.” Forest Stewardship Council United States, https://us.fsc.org/en-us/market/fsc-featured-products. 2019

This article shows that Lululemon yoga mats are FSC-Certified. It does not explicitly state that the natural rubber is a FSC-Certified material, but it highlights that raw material in the description of the product. The rest of the article are newly FSC- Certified products.

“Packaging & Waste.” Lululemon, 2019, info.lululemon.com/sustainability/our-footprint/waste.

The company measured their waste footprint in order to find ways to reduce their output. They looked at the waste for packaging and other areas of production, and provided some examples of how they have or wish to go about reducing waste. In distribution centers, Lululemon reuse and recycle more than 90% of their materials (soft plastics and corrugate used in transportation). There is also a box reuse program set in place that saves more than 1 million boxes every year. In product packaging, the sustainable product packaging policy was set in place to ensure fully recyclable at the end of the life cycle. One big change made in packaging was switching from paper based to FSC- certified materials. Lululemon is also a part of the Austrailian Packaging Covenant Organization, in which the company gives an annual report and action plan about APCO packaging sustainability framework. Recycling textiles is also being practiced; due to internal initiatives and partnerships over 90% of damaged or excess product is being resold, donated, or recycled. As for yoga mats, they are turned into equestrian footing product called Reiten Right. 

Perelshtein, Ilana, et al. “Sonochemical Coating of Silver Nanoparticles on Textile Fabrics (Nylon, Polyester and Cotton) and Their Antibacterial Activity.” Nanotechnology, vol. 19, no. 24, Dec. 2008, p. 245705., doi:10.1088/0957-4484/19/24/245705.

Silver nanoparticles are synthesized and deposited onto different fabrics to test the antimicrobial abilities. In this experiment ultrasound irradiation was used as a new method for coating the textiles. The silver nylon fabric showed the best results. Fabrics coated in nanosilver do have antibacterial agents. All materials are cheap and non toxic. 

“Polyester.” How Products Are Made, http://www.madehow.com/Volume-2/Polyester.html.

Polyester is a synthetic fiber. This material is made from coal, air, water, and petroleum. It is formed by a chemical reaction between an acid and alcohol. Polyester fibers can be very long. They are also very strong and stable.

“Polyurethanes.” How Polyurethane Is Made, 2019, https://polyurethane.americanchemistry.com/How-Polyurethane-is-Made/.

Polyurethanes are made by reacting a polyol, an alcohol with more than two reactive hydroxyl groups per molecule, with a diisocyanate or a polymeric isocyanate with the presence of a suitable catalyst and additive. Due to the variety of the diisocyanate and polyol, the product can come in an array of different forms. The product can be flexible foams, rigid foams, chemical- resistant coating, etc.. 

“The Best Arena Footing Additive To Keep Your Horse Sound: ReitenRight.” STABLE STYLE, 8 May 2019, https://stablestyle.net/best-arena-footing-additive/best-arena-footing-additive.

This article explains how the yoga mats are transported and made into equestrian footing. This article also gives the details on the benefits of the footing. There are also great pictures provided on this website of the yoga mats transformed. 

“The Reversible Mat 5mm.” Lululemon, 2019, shop.lululemon.com/p/womens-gifts-for-yogis/The-Reversible-Mat-5/_/prod6750166?color=33539&sz=ONESIZE.

This yoga mat is made out of polyurethane in order to absorb moisture and be easily wiped clean. The mat also contains latex and natural rubber to give cushioning and grip. In addition there is also an antimicrobial additive in the mat to help prevent mold and mildew that could possibly grow on the mat.

Ahtziry Vazquez

Professor Christina Cogdell

DES 040A

4 December 2019

The Embodied Energy of the Lululemon Yoga Mat

Lululemon Athletica was founded in Vancouver, Canada by Chip Wilson in 1998. This company is well known for their leggings, but the product chosen to evaluate and research its life cycle is the Lululemon yoga mat. Any yoga mat can be seen as a flat object that does not seem to require much detail when choosing the materials and the process in which it is going to be brought to stores. Yet, so much energy and processes are in the production of the mat that can go unseen. The materials extracted have a long process before even starting the product, the energy needed in transportation to distribute the materials to manufacturers, distributors, and stores, and the disposal of the damaged products is the number of steps that Lululemon has to take into consideration during the life cycle of the yoga mat. Through the cradle-to-grave processes of the Lululemon mat such as the material extraction, distribution, and disposal, the complexity of the embodied energy can be perceived. 

Energy Associated with Raw materials and Acquisition

Extracting primary materials and processing them into secondary materials involves large inputs of mechanical and thermal energy inputs. The main materials of the Lululemon mat are natural rubber, polyester nylon, and thermoplastic elastomer which are extracted from international suppliers. The raw materials that are used to make Lululemon products are collected from Australia, New Zealand, China, and South Africa (Stephensen, 2015). These are then transported through ships to the manufacturers at various locations.

Natural rubber starts off as a latex that is collected from the Hevea brasiliensis tree, originally from South America but it is now harvested in Southeast Asia or the latex can be collected from the Guayule shrub in Northern Mexico and Texas (Soratana, 2017). The harvesting of Hevea requires 1350 mm of rainfall, fertilizers, diesel, and pest management for 7 years of growth (Soratana, 2017). Land, water, soil, and human contact is needed when these trees are growing (Blaettler,  2019). After it is fully grown, the bark of the trees is cut by mechanical energy to extract latex (Soratana, 2017). On the other hand, the Guayule plant takes about 2-3 years to grow. (Soratana, 2017). This plant requires a lot of water so irrigation systems are used by mechanical energy, fertilizers, and diesel (Soratana, 2017). The latex in liquid form from the Hevea is put in large tanks on trucks so that it could be transported using fossil fuels to the processors (Blaettler, 2019). The transportation of Hevea is through trucks from the field to the processors which carries 14,960 kg for 60km (Soratana, 2017). The biomass of the Guayale is transported to the processors in which use diesel for trucks carrying 14690 kg for 150 km (Soratana, 2017). At the processors, the process of coagulation involves the rubber to be extracted from the latex which involves ammonia, electricity, LPG, and diesel (Soratana, 2017). The duration of this chemical process could be about 12 hours (Blaettler,  2019). This includes mechanical energy, chemical energy, and human labor. Once the rubber is extracted, mechanical energy is used to remove water from the rubber with rollers and the force of a human. Then the sheets of rubber are placed on “wooden racks in smokehouses” for solar energy or are air dried with hot air by mechanical energy (Blaettler, 2019). It may take several days for the sheets of rubber to be dried. After the sheets are dried, it is sent to the processor which would require fossil fuels to operate the transportation. The process at the factory includes “compounding, mixing, shaping, and vulcanizing” (Blaettler, 2019). Each of these steps involves chemical energy. During mixing, rubber is heated at 300 degrees fahrenheit. Shaping of the rubber requires chemical and mechanical energy because of the force of the human to mould the natural rubber. Vulcanization is the chemical process that makes rubber last longer and be capable of working in most temperatures with the use of thermal energy (Blaettler, 2019). Transportation of the rubber made from Hevea or Guayale to the manufacturers is either through truck or ship using fossil fuels.

Polyester and nylon are produced separately using separate sets of energy and later are chemically processed together. Polyester is produced through the sources of coal, air, water, and petroleum (“Polyester”). Petroleum is cheap so it is easily accessible (“Read ‘Polymer Science and Engineering: The Shifting Research Frontiers’”). There are four ways that the final polyester can take form in which is a filament, staple, tow, and fiberfill (“Polyester”). All of these forms need human labor to cut the material and thermal energy to heat the material in the process. Nylon is a plastic that goes through chemical processes of molecules and atoms. Nylon is not a material that can be extracted from nature and needs chemical energy. This plastic also uses coal and petroleum or might use a renewable source, castor oil (“Nylon - The Science of Synthetic Textiles”, 2019). Mechanical energy and mining will be need to get coal and the making of wells will be needed to get petroleum. Mechanical energy is used in the autoclave machine which is an “industrial strength kettle” (“Nylon - The Science of Synthetic Textiles”, 2019). Fibers of nylon are made by using thermal energy when melting nylon chips and placing them on a spinneret which works as a wheel. The wheel works as mechanical energy to create holes with different lengths and thicknesses of the nylon. This process creates the nylon to be waterproof and durable in any weather. The amount of energy used and pollution created for making nylon is higher than to transport the material (Van Der Velden et al, 2014). Synthetic nylon has the highest eco-cost and carbon footprint compared to synthetic acryl, PET, and Elastane for the whole production process (Van Der Velden et al, 2014).  The eco-cost for the life cycle of nylon is over 6 euro/kg for 70g/10km amount of material (Van Der Velden et al, 2014). This is lower than cotton but higher than acryl, PET, and Elastane which shows how much energy is involved during the production of nylon itself. Then chemically processing polyester and nylon would also require mechanical and chemical energy increasing the energy consumption during the production of these materials. 

Thermoplastic elastomer (TPE) goes through chemical processes and mechanical energy is required to shape this material in a desired way by the manufacturers. TPE contains rubber which gives them the characteristic of flexibility and also contains plastic. This material can be molded and reheated multiple times without changing the characteristics, only its shape (“Thermoplastic Elastomers: An Introduction”, 2018). So it does not require more production for a different length when it can just be redone. This material is recyclable and is minimal in energy use during the process (“Thermoplastic Elastomers: An Introduction”, 2018). The elastomer is placed on a calendar, alike to a mill, which has rollers that the sheets go through (Walker, 2017). The rollers are adjustable by a human depending on the desired thickness of the sheets. Energy consumption will vary depending on the thickness of the sheet (Van Der Velden et al, 2014). Compression moulding, an inexpensive moulding machine, used to shape the elastomer (Walker, 2017). Mechanical energy is then used to cut the elastomer with knives or scissors by a human. The elastomer is then placed in an oven to get rid of any residue. Inspectors test and final inspections on the elastomer in order for it to be packaged with caution to the manufacturers of other companies (Walker, 2017).

Manufacturing Processing and its Energy Use

The materials are joined through chemical and mechanical processes that gives the Lululemon mat its characteristics for proper use. Since Lululemon does not own or operate their own manufacturing facilities, they have manufacturers overseas (“Lululemon Supplier, Manufacturer, and Distribution Overview”, 2014) The materials extracted for the production of the Lululemon mat are sent out to the manufacturers.

In the manufacturing process, thermal energy takes place to heat the materials and mechanical energy is used through the machines and the human labor required to cut and pack the mat. The natural rubber is used for the bottom layer. Polyester nylon is an absorbent material placed as a top material while silicone, acrylic, or TPE is worked as the second top material for friction. The thermoplastic elastomer is utilized for the foaming of the mat. For the foaming, the thermoplastic elastomer needs to be set in an oven to be heated. The top and bottom layers of the mat are laminated and heated together in an oven for about 5 to 7 minutes in 120 to 150 Degrees Celsius (Dandapure and Douglas, 2013). When this process is occuring, there is pressure on the top and bottom of the fabric by using the calendaring machine which involves mechanical energy. Both of these layers are moved throughout by a belt on heated chambers (Dandapure and Douglas, 2013). It is then cooled down and cut to the size of the mat which is about 26 inches by 71 inches. The silicone ink placed on the top material is heated in a chamber at 200 Celsius for 90 seconds or screen printing are also used for this process and then it is set to cool down (Dandapure and Douglas, 2013). The final step would be that the acrylic material that is used to add traction to the mat is heated in an oven at 170 to 200 Celsius for 45 to 120 seconds (Dandapure and Douglas, 2013). It is cooled and packed as a final product through human labor.

Distribution and Transportation Energy Consumption

The distribution of Lululemon products is done by ocean using fossil fuels, electricity, and heat to run the ships and energy is used to distribute finished products to various locations internationally. Fossil fuels for the use of ships come from oil, gas, and coal (Van Der Velden et al, 2014). Lululemon third party providers such as warehouses are located in Hong Kong, China, and the Netherlands (Baalbaki et al, 2019). The products are distributed to five distribution centers which include the U.S., Canada, Australia, and Ohio (Baalbaki et al, 2019). The distribution center in Ohio allows ground transportation with the use of loaded trucks (Baalbaki et al, 2019). The impacts of emissions from these transportation to air, water, and ground are eco-toxicity, carcinogens, summer smog, eutrophication, acidification, and global warming (Van Der Velden et al, 2014).

Lululemon works with Damco to transport their products from manufacturers and suppliers to the distribution centers and from there to the stores at which the products will be sold. Damco offers in country transportation, international transportation, warehouse operations, and port operations (Blanco and Craig, 2009).  Damco is located in the Netherlands, Africa, Europe, North America, Oceania, South America, and Asia (Stephensen, 2015). Most of their transport occurs through ocean than air. The reason for this is that “cargo transport by ocean carrier is 50 percent to 70 percent more efficient in terms of emissions than air carriage” (“Running on Sustainable Logistics”, 2011). The energy reduction from air to ocean is significant. Transport by ocean allows the embodied energy to decrease. Lululemon is cautious with who carries their products and the process of the transportation of their products in order to have control over the impact of their process with the environment.

Energy in Use, Reuse and Maintenance

The use of the mat depends on the person and how a person takes care of the product. It is stated in a study of the life cycle of nylon that the users are starting to use lower temperatures in washing machines. The temperature at first was 60 degrees celsius and now the temperature used is 40 degrees celsius which saves 40% of electricity (Van Der Velden et al, 2014). For yoga mats, dryers are not recommended instead the mat should be air dried. Energy consumption from dryers is about 0.55kWh/6 kg which is higher than washing machines (Van Der Velden et al, 2014). The mat is used for the friction and flexibility to be rolled and portable. The human is guaranteed that their Lululemon mat should be usable for about 5 years (Stephensen, 2015). There is not a lot of maintenance, just how well a person can take care of it. The mat may become unclean, but it should last a while. Until it is fully damaged or unusable as a mat, the materials can be recycled.

Energy Use during Recycling and Waste Management

In the Lululemon mat, only some materials such as the thermoplastic elastomer are recyclable which can be reworked through mechanical and chemical energy and the other materials would be sent to the landfill by transportation and human labor. But Lululemon states that “over 90% of our damaged and excess products are resold, donated, or recycled” (“Sustainability”). The Nylon material can be recycled but only some of what was recycled is wearable (Van Der Velden et al, 2014). Since the material is already made and it just needs to be reworked. Yet, human labor would be necessary to carry and separate these damaged products from the useful products. Transportation back to the factories will need fossil fuels to run. Rubber waste, on the other hand, is easier to just throw away in the landfill and it is not biodegradable (Imbernon and Norvez, 2016). Rubber waste can also be used as a fossil fuel which would require chemical energy but it helps recover energy that went into that rubber (Imbernon and Norvez, 2016). The thermoplastic elastomer contains plastic that can be recycled, which conserves energy and the material (Jiun et al, 2016). The thermoplastic plastics are melted and go through chemical processes in order for it to be recycled (Jiun et al, 2016). The whole mat cannot be recycled since only parts of the materials are unusable and have to be thrown out into landfills using mechanical energy, chemical energy, and fossil fuels. 

It is not specified whether the damaged products are from the companies or the consumers. If there is not recycling centers specifically for Lululemon products, consumers are more likely to throw out the mat to the landfill in which energy is not conserved or saved for used products.

Overall, the extraction of the materials, methods for distribution, and disposal sites for the Lululemon mat are long processes that require a large amount of embodied energy. Lululemon has explored for solutions to limit the total embodied energy impacting the environment in a negative manner. Implications of this research was that information on the travel distance length and specific machines used during the manufacturing of the mat are not given which would have been useful in including as part of embodied energy. As it has been discussed, the embodied energy is intense during the life cycle of the Lululemon mat in which at the end of the life cycle, a few parts of the material can be recycled and energy can be conserved.

Bibliography

Baalbaki, Sally, Debora J. Gilliard, and David Lynn Hoffman. "Is Lululemon Athletica’s Turnabournd Sustainable?." American Journal of Management 19.2 (2019).

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Imbernon, Lucie, and Sophie Norvez. “From Landfilling to Vitrimer Chemistry in Rubber Life Cycle.” European Polymer Journal, vol. 82, 2016, pp. 347–376.

Jiun, Yu Lih L, et al. “Effects of Recycling Cycle on Used Thermoplastic Polymer and 

Thermoplastic Elastomer Polymer.” Polymers and Polymer Composites, vol. 24, no. 9, 2016, pp. 735–740.

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Soratana, Kullapa, et al. “Guayule as an Alternative Source of Natural Rubber: A Comparative Life Cycle Assessment with Hevea and Synthetic Rubber.” Journal of Cleaner Production, vol. 159, 2017, pp. 271–280.

Stephensen, Kristin. “Posts.” Commodity Chain Project Lululemon Athletica, 28 Apr. 2015, https://u.osu.edu/commoditychainlululemon/. 

“Sustainability.” Lululemon Athletica, https://info.lululemon.com/sustainability. 

“Thermoplastic Elastomers: An Introduction.” Comar, 14 Nov. 2018, https://www.comar.com/news-room/thermoplastic-elastomers-an-introduction/. 

Van Der Velden, Natascha M. M, et al. “LCA Benchmarking Study on Textiles Made of Cotton, Polyester, Nylon, Acryl, or Elastane.” International Journal of Life Cycle Assessment, vol. 19, no. 2, 2014, pp. 331–356.

Walker, James. Elastomer Engineering Guide. 2017, https://www.jameswalker.biz/de/pdf_docs/148-elastomer-engineering-guide.

Rachel Tam

Des 40a, A05 

Professor Christina Cogdell

04 Dec 2019 

    Considerations on the Waste and Emissions Throughout a Lululemon Yoga Mat’s Lifecycle

A popular method to increase relaxation and promote health, yoga has emerged as a  prominent trend in our society. Furthering the yoga craze Lifestyle brand, Lululemon Athletica, has catered towards comfort and curated their own yoga mat. Lululemon Athletica's yoga mat is primarily composed of the materials: polyurethane and latex/natural rubber. While polyurethane has favorable properties, much of the material is manufactured with petroleum-- which can negatively affect our environment during the waste emissions breakdown. Latex, another fundamental component of the yoga mat is deemed “natural” but often includes additional substances like sulfur and zinc; which in time, may alter the degradation process and add hazards to the waste breakdown. While the materials used in the Lululemon Athletica yoga mat may seem environmentally friendly, the primary materials entail an overlooked environmental cost throughout its cradle-to-grave waste and emissions process. 

Known for their environmentally conscious policy, Lululemon Athletica strives to maintain a material recycling philosophy. To achieve their goal, Lululemon uses sustainable materials in their products, conducts a yearly carbon footprint, and assesses their overall energy output. (Gilliard, et al., 2019) The origins of the yoga mat’s main materials-- latex, polyurethane, and nano-particles of silver-- initially come from natural substances. (Lululemon, 2019)  How the raw materials for latex and polyurethane are acquired for the Lululemon yoga mat are crucial to understanding the waste aspect of the cradle-to-grave process. Through the process of coagulation, compounding, and lubrication, latex goes from a raw substance to a polymer based material. (Myers, 2019) Retrieved from the Hevea brasiliensis, or Para Rubber Tree, latex seeps out from their slitted tree trunks as a sappy, white liquid. (Myers, 2019) Since the Para Rubber tree is native to the moist Amazon rainforests and grown in regions of Southeast Asia, latex must be transported to the Lululemon manufacturing factories. (Rainforest Alliance Organization, 2019) In terms of being transported to the manufacturing factory, our primary concern regards the waste released through transportation-- most likely from airplane or ship. Both car and ship contribute to pollution by releasing carbon dioxide into the atmosphere. Carbon dioxide releases harmful toxins like black carbon, nitrogen oxides, and nitrous oxide which trap heat in our atmosphere and contribute to greenhouse gas waste. (Oceana, 2019) Polyurethane is the other main material involved in the Lululemon Athletica yoga mat. Polyurethane is favored for its durability, flexibility, and water resistant properties -- making it a very fitting yoga mat material. (American Chemistry Council, 2018) Polyurethanes are derived from oils (Guo, et al., 2014) and according to the American Chemistry Council, “Polyurethanes are formed by reacting a polyol (an alcohol with more than two reactive hydroxyl groups per molecule) with a diisocyanate or a polymeric isocyanate in the presence of suitable catalysts and additives.” In terms of waste emissions released from reacting a polyol, there is a small amount of pentane and carbon dioxide released when the polyol reacts with the polyisocyanate. (Essential Chemical Industry Organization, 2017) While Pentane may be a health hazard in large amounts, in this situation very minimal is released; thus the colorless gas is harmless to our environment/health in this situation. (National Center for Biotechnology Information, 2019) Like pentane, the small amount of carbon dioxide released is also not detrimental in terms of  waste. Composed and sewn in with a few strands of polyester and nylon, polyurethane presents itself in a variety of forms. Chemical resistant coatings, adhesives, flexible foams, rigid foams, and elastomers are all various forms polyurethanes have the ability to become. (American Chemistry Council, 2018) Unfortunately, Lululemon Athletica does not specify the form their polyurethane takes; but because our product is a yoga mat, we can assume polyurethane is either rigid foam or flexible foam. When rigid polyurethane foam is created, much of it relies heavily on petroleum components. (Gonzalez, et al. 2017) Due to its high flammability, emitted petroleum gas can cause fires, which contribute to the pollution in the air. (National Center for Biotechnology Information, 2019) Thus while the Lululemon Athletica boasts an environmentally friendly approach, there is still concerning matters in the waste emissions life cycle break down.  

In terms of manufacturing, the majority of the waste comes from additional chemical involvement and machinery use in creating polyurethane and latex. In order for polyurethane to be created, it requires high pressure equipment for merging the various chemicals together. These high pressure equipment machines are powered hydraulically, which have the potential to leak toxic hydraulic fluids and oils. (American Chemistry Council, 2019) Leakage can lead to health problems, fires, and can be corrosive to the surrounding environment; the waste output involved in the polyurethane manufacturing is quite hazardous. (Gillespie, 2018) When latex is manufactured, it undergoes a series of compounding, mixing, shaping, and hardening. During compounding, the latex is treated with high temperatures for heating, stabilizing the polymers and making the latex brittle and gooey. (Blaettler, 2018) In this process waste is minimal, as he cooling of latex comes from exposure to natural air and sunlight. (Lambert, et al., 2013) Following this stage is mixing, adding chemical fillers like carbon black, aluminum silicate, and occasionally recycled rubber particles. Due to the current state of resistance to flow and mixture, 300 degree fahrenheit heat is often utilized for slight latex melting. (Blaettler, 2018) While the source of heat is not specifically stated, one can assume it comes from either artificial appliance heat or fire. When fire burns, it emits greenhouse gasses, like carbon dioxide into the air; carbon dioxide contributes to the waste into the air we breathe. Additionally, the process requires large amounts of energy and heat, but significant portions of the greenhouse gas (GHG) production comes from burning fossil fuels to produce electricity at the power plants, which fuel the manufacturing factories. (Lim, 2019) After, the latex is shaped with different techniques, including extrusion and coating. During extrusion, the latex is flattened under a series of mechanical rollers. (Blaettler, 2018) In coating, latex receives a rubber coating from the same mechanical rollers used to flatten it. (Blaettler, 2018) Following this stage comes vulcanization, or hardening of the latex. During vulcanization, the latex is heated up for about five hours allowing the latex to fully harden. In addition to the heat, sulfur and zinc are also added to the latex for speeding up the heating process. (Lambert, et al., 2013) With sulfur and zinc being added to the latex it can increase the emitted toxins during the waste emissions breakdown. (Lambert, et al., 2013) In addition to the greenhouse gasses emitted from the fire, when sulfur is degraded it has the ability to oxidize and become sulfur dioxide. (Environmental Protection Agency, 2019) In a worst case scenario, over time, massive amounts of sulfur dioxide released into our air can become harmful to humans and plants in the surrounding areas. (Environmental Protection Agency, 2019) Additionally, when exposed to other particles in the air sulfur dioxide can create haze, smog, and contribute to acid rain -- which destroys our ecosystem. (Environmental Protection Agency, 2019) Like sulfur, when zinc degrades it emits sulfur dioxide; additionally nitrogen oxide and dust also are released from zinc. (Berdowski, et al., 2017) Thus, while the yoga mat’s manufacturing process may seem harmless, the materials waste emissions process may be threatening to the environment and can pollute the air we breathe.

After the manufacturing process, the Lululemon yoga mat is transported to the company’s various store locations and distributed to purchasing customers. While Lululemon Athletica’s primary mode of product transportation is not specified, we can assume by the amount of overseas factory workshops it is by ship or plane. Today, airplanes account for 2.5% of global carbon dioxide emitted into our air. (Tabuchi, 2019) Additionally, airplanes are primarily responsible for the excess water vapor in the stratosphere and troposphere which holds responsibility for shielding high levels of radiation from the sun from the earth. (Banu, 2011) With shipping products, the carbon footprint is slightly reduced, but still contributes to emitted waste. Because shipping transports 90% of goods globally, it accounts for 3% of the global carbon dioxide released into the air. (Cowing and Selin, 2018) Shipping causes air pollution, unnecessary oil production, and emits greenhouse gasses which all negatively impact sealife and imbalance the Ocean’s chemistry, which can potentially cause ocean acidification. (Pirotta, et al., 2018) As we evaluate the transportation waste emissions of shipping and air travel we see how each contributes to air pollution and greenhouse gas emissions. 

Post transportation, distribution, and customer purchase comes utilization, reuse, and maintenance. As the Yoga mat is engineered to last for multiple uses, built with durability, elasticity, and embodies a waterproof properties, it does not require high maintenance. In terms of maintaining the Lululemon yoga mat, such as wiping excess sweat or other bodily fluids off, a wet wipe, damp cloth, or paper towel would fulfill the task. In the use stage of the life cycle, a good consumer fulfills the job to maintain their yoga mat. And in order to maintain the yoga mat in good condition, the cleaning products entail a small environmental costs associated with those items. 

When evaluating the recycling and waste stages of the Lululemon Athletica yoga there are two primary options for retired polyurethane foam, rebonding and regrinding. (American Chemistry Council, 2018) The rebonding option recycles about 90% of all polyurethane foam. (American Chemistry Council, 2018) In the process, polyurethane foam is shredded into small flakes and placed in a blender/mixer for vigorous mixing. (Datta et al., 2018) Afterwards, the shredded polyurethane foam is molded and compressed into the user’s desired shape by hot steam and pressure. (Datta et al., 2018) In terms of waste and emissions, our primary focus is the waste from the blender appliance, and the appliance used for pressure and hot steam. While the type of blender is not specified, we can assume the appliance is powered by electricity, which is powered by fossil fuels -- coal, petroleum, and natural gas. When these fossil fuels are burned, they release GHG, and create pollution. Additionally, the other appliance used to create hot steam and pressure would most likely also be powered by fossil fuels, probably coal. When coal is burned, it releases a multitude of toxins into our air; these pollutants include mercury, lead, sulfur dioxide, and nitrogen oxides. (Union of Concerned Scientists, 2019) Additionally, coal can also pollute our waters; as many coal fired power plants leak ash into nearby streams, lakes, and landfills. (Union of Concerned Scientists, 2019) As a result of contaminated bodies of water, if a living creature were to drink the coal-waste infected water, it would jeopardize your health. The other option of regrinding turns polyurethane foam into fine powder. (American Chemistry Council, 2019) The foam is grinded by machines with several sharp knives, and cooled with liquid nitrogen if the foam is above embrittlement temperature. (Datta et al., 2018) Regarding waste, our primary concern is how the sharp knife machine is powered. While the machine is not specified they article, we can guess it is most likely powered by electricity. Thus, the primary waste emission would be fossil fuels, and the pollutants fossil fuels release. Like the blender, the concerning matter refers to the release of GHG and how they lead to air pollution, global warming, and water pollution. Additionally, any other Lululemon yoga mats are most likely transported to landfills by trucks or cars. In that situation, we would just evaluate the average carbon footprint of a car -- which is about 4.6 metric tons of carbon dioxide per year. (Environmental Protection Agency, 2019) As every gallon of gasoline burned creates about 8,887 grams of CO2. (Environmental Protection Agency, 2019) In addition to the CO2 emitted by cars, gas powered vehicles also release methane and nitrous oxide from the tailpipe and hydrofluorocarbon emissions from leaking air conditioners. (Environmental Protection Agency, 2019) The amount of these emitted wastes are small in comparison to the overall CO2 an automobile emits, but can build up with time, and contribute to global warming and pollution. (Environmental Protection Agency, 2019) All in all, we can see how quickly waste can accumulate in the recycling stage of a Lululemon yoga mat, leading to harmful environmental repercussions.

While the Lululemon yoga mat will continue to be purchased by yoga enthusiasts, it has not completely become an environmentally friendly product. With Lululemon’s environmental sustainability approaches and assessments, they have not mastered a product with complete earth friendliness in terms of waste and emissions. With the traces of petroleum in Polyurethane and sulfur in Latex, they both emit toxins into the air when they are broken down. (Lambert, et al., 2013) Additionally, Latex’s synthetic mixture with substances like zinc and sulfur raise concerning issues, as both contribute towards polluting our environment. When we evaluated the environmental drawbacks of transportation by air and sea, we saw how each contribute to pollution and emit harmful toxins for humans, sealife, and our atmosphere. In usage, we see the results of how low maintenance purchasing a yoga mat is. And when we assessed the yoga mat’s recycling stage, we saw that some yoga mats retired by becoming stuffing for mattresses. On the other hand, if the yoga mat was left to decompose by itself, it would emit Nitrogen, Zinc, and Petroleum into the atmosphere to destroy and pollute our ecosystem. All in all, while Lululemon claims their products are environmentally sustainable, their waste emissions output still has room for improvement in the cradle to grave process.

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