Design Life-Cycle

Vanessa Tran

Professor Christina Cogdell

Des 40A

1 June 2024

Raw Materials and Manufacturing of Nylon Crescent Bag

Bags have a significant role in the fashion industry, not only is it practicality, it also can set a statement. For example, the Baggu Nylon Crescent Bag is a popular choice when choosing a bag. Even though it’s not a luxury brand, there are many designs to obtain this bag. This is because of its distinctive crescent shape that aligns with the modern aesthetic. It is made with recycled nylon, which helps divert discarded materials and reduce greenhouse emission. The most common nylon used in making textiles are nylon 6 or nylon 66. There are two ways to turn recycled nylon 6 and nylon 66 into textiles. It can be recycled through a chemical or mechanical recycling process. Although BAGGU uses recycled nylon it is still important to mention that nylon primary raw materials are coal, water, and air. This is important to mention because without the nylon created through the primary raw materials, there would be no recycled nylon. The process to create the recycled nylon is an important process as well as their other life cycle; manufacturing, distributing, maintenance, recyclability and waste management. When discussing the life cycle assessment of the Nylon Crescent Bag it is important to analyze secondary raw materials used in its production like recycled nylon, showing the systems used to create them.

In each seven stages of life, the process of creating the Crescent Bag seems to be made of the same raw materials, but the zipper. BAGGU lists nylon as the only material used to create the Crescent Bag. When looking further into the website it says “59% recycled materials” (Baggu) for the heavyweight nylon. While Baggu never mentions which type of nylon is used, the most common nylon used in making fabric is nylon 6 or 6,6. So it is safe to assume that Baggu uses either of these nylon, since these are the most commonly used and recycled. Baggu claims that their nylon style bags all come from recycled nylon filament yarn that are produced from pre-consumer waste. Although Baggu never explains the process of how the pre-consumer waste is acquired and how they produce their secondary raw material into the yarn that create these popular bags. This research paper is based on the theoretical way Baggu acquired their pre-consumer waste and how it is manufactured into the fabric needed to make these bags.

Recycled nylon comes from post industrial collections, this can be from any company donating or buying it off of the company. This can be from discarded fishing nets, fabric scraps, carpet flooring, and industrial plastic. Most of the time the waste is collected from the ocean (RebornPlas). Once the initial collection it will then be sorted, baled, and shredded. Since the recycled nylon comes from many different wastes, it must be sorted by the type and its color. After the sorting it must go through a cleaning process to ensure any type of contamination is removed. Once it is clean the ‘real’ process begins, this is when the company picks the process they want to recycle; chemical recycling or mechanical recycling (RebornPlas).

Chemical recycling is transforming the polymeric waste into substances that can be reused as its raw materials. The chemical recycling process involves depolymerization. It is shredded through a shredding machine making it into smaller pieces. After shredding the nylon scraps, it is melted into its molten state or into plastic pellets. This is now when Baggu decides the chemical recycling process or the mechanical recycling process. There are many different types of chemical processes, but this research will focus on solvent-assisted depolymerization, hydrolysis, and pyrolysis. Solvent assisted depolymerization is when nylon 6 becomes depolymerized using a high boiling point. The point of this solvent is to disrupt the structure of the polymer to make it into high temperature and then facilitate the intramolecular cyclization of the amino groups to form caprolactam. This process is used mainly on a laboratory scale. Hydrolysis is a reaction where carboxyl amide is attacked by water molecules; this process can be used on either nylon 6 or 66. The process requires high temperature and pressure and it uses either acid catalyst or alkaline reagent. If the catalyst is acid based the process exploits the acidic substances to lower the activation energy, which breaks the polymeric chains. This type is mainly used for nylon 6. If the catalyst is alkaline, it exploits the nucleophilic reagent. This is done by the -OH breaks the amide bonds and recovers the monomer such as caprolactam and 1,6-hexanediamine. This is mostly used for nylon 6. Although this is one choice to recycle, the negative is that it is limited because it requires high energy usage, high chance of contamination, and the cost is high. Chemical recycling is more sustainable and green, but the cost is high and the energy required is high compared to the mechanical recycling route. (Tonsi, Maesani, Alini, Ortenzi, Pirola).

Thermomechanical recycling is the most common process used when recycling nylon. This process involves grinding and some re-extrusions of plastic waste to recycle (. The first step is shredding and grinding the recycled nylon into smaller pieces. The smaller pieces will then be melted into chips or pellets from here the fabric will be put into a machine called the spinneret. This will be discussed later in the paper. The type of recycling process is better to be performed with post industrial processing waste compared to the post consumer nylon waste. The main reason is because industrial processing scraps are more likely to be homogeneous and uncontained. A fundamental procedure for thermomechanical recycling is drying, this is because it will ensure the water content is as low as possible during the processing stage. The less water content the less molecular weight, which will be easier to stabilize and be good quality. This is especially important when continuously recycling the nylon over and over again. The negative to this type of recycling is because of the high temperature needed to use this process the recycled nylon quality is jeopardized. Mechanical is a great choice because of the low cost and less energy usage, but it has a high chance of being contaminated and of bad quality. (Tonsi, Maesani, Alini, Ortenzi, Pirola)

The spinneret is required when making the chips into the filament and then woven or knitted into the fabric used for the bags. To turn the nylon waste into the nylon fabric after picking either chemical or mechanical recycling style it will start being melted and then put through a spinneret, forming a filament of the nylon fiber. A melt spinneret is a common method when producing synthetic tactile files (Rarleton and Wakeman). It is involved in the nylon pellets being melted while spinning, while being pushed out cold air is blasting on the fibers to solidify it [Figure 1]. Once the fiber is collected it is taken to a wheel to be stretched into the yarn (Testile-FlowChart). Although this was never mentioned by Baggu, instead on their website there is a picture of a JUKI sewing machine [Figure 2]. The only thing mentioned is “our reusable bags are assembled from one continuous piece of recycled nylon material…” (BAGGU).

When researching it is possible for the strap and the buckle part to be created with nylon. “Nylon webbing is a sturdy and easy choice for tote bag straps” (Humbach). Although this mentions a tote bag, this shows that bag straps can be made out of nylon. Furthermore, buckles can also be made up of nylon, “Common plastic materials used for belt buckles includes … nylon …” (Cooper). This help shows that the Crescent Bag can be made up of mostly nylon. Baggu never mentioned the material of the zipper. Although the zipper is most likely made out of metal, it is possible for it to be made out of nylon. If it is made out of metal, the metal type is not listed but zippers are commonly made with stainless steel and zinc. To obtain the raw material of stainless steel it is a combination of chromium, nickel, silicon, manganese, carbon, and nitrogen. Nickel, zinc, silicon, manganese, and chromium are all mined to obtain. Chromium is the most important part when making stainless steel (metalsupermarkets). The manufacturing process requires melting the metals all together in an electric arc furnace until it becomes a molten (metalspermarkets). The motel is then transferred into an Argon Oxygen Decarburization vessel where the carbon levels are reduced and any other alloys are added to make the stainless steel (ssina). This is the molten is then melted and casted into stainless steel. From here the material is hot rolled or cold rolled and forged into its final form. [Figure 3]. While if ti is made out of nylon it is also known as a “coiled zipper is made of plastic elements as polyester or nylon”(YKK). “Serveral materials create metal zippers- Aluminum,stainless steel, zinc… On the other hand, zippers consisting of plastic materials contain nylon or polyester, with the slider being steel” (FixnZip). 

The secondary raw materials that Baggu uses is beneficial for the environment because instead of the nylon just being waste, it is created into a fashion piece. Baggu claims “to minimize waste… we work to eliminate waste during the actual construction of our products” (Baggu). This shows it is safe to assume that Baggu has little to no waste when constructing the pattern or the bag.

To conclude, Baggu claims to use recycled nylon. But during my research I was unable to find the way they manufacture the nylon, the specific type of nylon use, and how the recycled nylon is collected. I was also unable to find out how their zipper was made and the raw materials required in making the metal zipper. In this research, I research in depth the possibility of how Baggu did the manufacturing, the type of nylon used, and the collection of the nylon. The lack of information on acquiring and manufacturing the secondary raw material makes it hard to assess the life cycle of the Nylon Crescent Bag made by BAGGU. Unfortunately with the lack of information it is hard to know the environmental impact and the verification of sustainability.

Bibliography

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Breanna Sanders

DES40A

Professor Cogdell

Nylon Bag Life Cycle Analysis: Energy

When in the market for a new, fashionable bag that is ethically made, it’s very probable that the brand Baggu enters your search findings. Baggu is very popular among young adults for its trendy, aesthetic, and sustainable practices. Along with being sold in the brand’s storefronts, Baggu products are featured in mainstream brands such as Urban Outfitters. When understanding the life cycle of a product, there are three sections to consider: materials, energy, and waste. This paper will describe the energy required to make Baggu’s popular Crescent Bag, which starts early in the original production of plastic, onto its recycling into nylon, in the manufacturing process, through transportation and shipping, and up until it reaches its end of its life cycle in landfill.

The first step in creating the Crescent Bag is to acquire the raw materials. As described on their website, the Baggu Nylon Crescent Bag is made up of recycled heavyweight nylon, lined with ripstop lining, able to close with a zipper, and made carryable with the logo strap (“Small Nylon Crescent Bag”). None of these materials are raw, primary materials extracted from the Earth, so let’s elaborate on the beginnings of each of those materials. Starting off with the heavyweight nylon, which is made of 59% recycled material (“Sustainability at Baggu”), the recycled material that is used to make the nylon is plastic waste before it reaches the landfill. The ripstop lining is 100% recycled nylon; the primary materials to make recycled nylon include “discarded non-woven nylon carpets, used nylon fishing nets, plastic bottles, plastic bags, nylon yarn waste, scraps, and trimmings” (Nguyen). The energy required to obtain these materials are much lower than to produce virgin plastics, which often require more fossil fuels for the manufacturing as well as transport processes. The collection process can be done mechanically and by hand, most probably a combination of both.

As for the logo strap and zipper, Baggu doesn’t disclose on their website the specific materials used to construct them. The strap seems to be made of recycled nylon, plastic adjusters, and plastic and metal clips at the end of each side. The zippers are made out of metal, stainless steel and zinc being popular materials (Secrest). To make stainless steel, a variety of elements are extracted or recycled; some of the most popular are “iron ore, chromium, silicon, nickel, carbon, nitrogen, and manganese. Properties of the final alloy are tailored by varying the amounts of these elements” (Millberg). To extract iron, there are a variety of methods that can be implemented, varying in energy requirements. Again, Baggu does not disclose the methods in which they extract their primary materials, but given their sustainability driven goal, I assume that they try to actively stay current on the most effective extraction methods, such as solvent extraction. In the 2024 published paper “Extraction and separation of iron technology and research progress”, researchers explain the popularity of solvent extraction due to its low energy consumption, simplistic and preservational properties, lower pollution, and “production of high-purity iron products for easy recovery”. This form of iron extraction is liquid-liquid, with an extractant such as hydrochloric acid (or another similar leaching acid) and an aqueous form of iron, such as Fe2+ or Fe3+. There are multiple processes to separate the extractant and product, such as single-stage extraction, multistage cross-flow extraction, and multistage countercurrent extraction; from these options, single-stage extraction requires the least energy and most simple operation and machines (Yu et al.).

The following step in the life cycle of the Crescent Bag is to manufacture the product from the primary materials. To manufacture the collected plastic into nylon material, there are two common processes: chemical and mechanical recycling. Baggu doesn’t disclose which manufacturing process they use to make the Crescent Bag.

Of the two processes, mechanical recycling is far more environmentally friendly because it reduces the hazardous by-product waste and does not require toxic chemicals to dissolve the plastic. In mechanical recycling, the plastic waste is sorted, cleaned, shredded into small pieces, reprocessed with heat and pressure, and then again reprocessed into recycled nylon fibers with the stretching, drawing, weaving process similar to that of virgin nylon (Nguyen). The mechanical recycling process requires much less energy and fossil fuels than chemical recycling and virgin nylon production, primarily due to its recycled primary materials that don’t require the same amount of fossil fuels for extraction. The sacrifice for this practice, though, is lower quality products with degraded polymers that lead to a shorter lifespan; “[m]ost plastics can only be mechanically recycled 3 to 7 times. This means that making nylon fibers truly circular using the mechanical route is impossible” (Nguyen).

As for chemical recycling, after material collection and cleaning, it undergoes depolymerization before undergoing a similar process to virgin nylon of “polymerization, extrusion, loading, stretching, drawing, weaving/knitting and finishing”. This process is considered energy-intensive, largely due to its fossil-fuel energy source (Nguyen). As of 2020 in China, where Baggu is manufactured, it is reported that 16.02% of energy sources are renewable, meaning that a majority is sourced from fossil fuels or other non-renewable sources (Ritchie et al.). One pro to chemical recycling, though, is that the recycled nylon and more closely replicate the quality of the original fabrics, since the same monomers can be produced; this aspect closes the nylon production loop (Nguyen).

For manufacturing the zipper, the iron and other metals have to be melted and formed to the zipper shape. In stainless steel production, typically an electric furnace of extreme heats is used to heat the metal for 8 to 12 hours, then formed through a variety of rolling, slabs, and shaping operations. After finishing the process with more heat treatment, descaling, cutting, and finishing, the zipper is ready for assembling (Millberg). These processes for creating the zipper require mechanical energy, specialized machines, and skilled workers. Unless the factories are powered by renewable energy, it can be assumed that fossil fuels run the operations.

For assembling the Crescent Bag, Baggu states that they have teams manufacture their products in China. Once the recycled nylon and other materials are ready for use, human labor is a main energy source, along with electrical energy to power sewing machines and run the factories. In their Code of Conduct, Baggu states that they care about fair compensation and working hours for their employees, so the outputted human labor is not exploited (“Code of Conduct”).

Continuing through the life cycle sequence, the assembled Crescent Bag is now ready for transportation and distribution. FedEx and USPS are two main carriers that Baggu uses to transport their products (“Shipping”). USPS has a clearly outlined sustainability plan to decrease their energy footprint by 25% by 2030; by the end of fiscal year 2023 they have progressed 7%. Some efforts that they have implemented include primarily using ground shipping, even though air shipping can be faster, to limit their environmental contributions. They also have begun to use renewable energy sources via solar in two major sites (one in Washington D.C. the other in Springfield, MA). The company receives RECs (renewable energy certificates) when energy is delivered to the grid from a renewable source. Additionally, USPS has invested in the production of Next Generation Delivery Vehicles, which will be 100% electric by 2026 (“2023 Annual Sustainability Report”). FedEx also has a sustainability plan to limit their environmental impact, which includes transferring to electric vehicles, beginning their experimentation with sustainable vehicle and aviation fuels, integrating energy efficiency in their building operations, and (slowly) implementing renewable energy sources, such as solar installations. When shipping internationally, it’s reported that FedEx takes about 4-6 business days and USPS takes 6-11 business days (“Shipping”), which could be due to the fact that USPS aims to use ground transportation as much as possible to minimize environmental effects, creating a slower delivery time (“2023 Annual Sustainability Report”).

Once the Crescent Bag arrives to the expectant customer, the use and reuse of the product requires no energy, the maintenance via machine washing and drying being the most energy taxing element of this stage in the life cycle. Most washers and dryers require electricity, which is commonly run via fossil fuels. Washing machines use about 200-1050 watts per load and dryers typically require 2250-3000 watts per cycle (“How Much Electricity Does a Washer and Dryer Use?”). One drawback of recycled nylon is its contribution to marine microplastics from the washing process (Nguyen).

The final stage in the life cycle of the Nylon Crescent Bag is recycling and disposal. The bag is made of high enough quality that it should last the consumer decades. If disposed, the bag would most make it’s way to the landfill, requiring transportation to get there, where it would take decades to decompose, with contaminants surviving and “hindering the recycling process” (Nguyen). If a consumer doesn’t want to possess the bag anymore, they should donate or resell it to continue its use.

To conclude this life cycle analysis on the Nylon Crescent Bag, I want to remind that energy is required for each step, from raw material acquisition through manufacturing, to transport and distribute the product, in the cleaning of the bag, and into its final descent into the landfill. The most energy taxing steps seem to be in the first three steps, for material acquisition, manufacturing, and transportation. Recycled nylon is unsustainable, since it lacks a sustainable disposal and reintegration process, but the sourcing of discarded plastic waste as a primary material is positive in its production.

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