How is polyester (PET) recycled?

David Platt • 29 June 2021

How does a PET drinks bottle become a T-shirt?

In the world of eco promotional goods there are a number of products including t-shirts, bags and umbrellas which are made from recycled polyester sometimes referred to as rPET. What is it? How does a polyester soda bottle end up as a T shirt? And, most importantly is rPET really eco-friendly? This article is meant as an introduction and hopefully answers those questions.

So what is polyester?

Polyester or polyethylene terephthalate, known as PET is one of the most common plastics produced with 18% market share, after polythene (33.5%) and polypropylene (19.5%). PET has a range of uses for both consumer products and industrial uses but the most common is a fibre for the manufacture of clothing:


*Product Type*	Million Tonne produced 2016
Textile Fibre	39
Bottle Resin	16
Film	1.5
S pecialist	2.5
*TOTAL*	59

Source: https://www.plasticsinsight.com/resin-intelligence/resin-prices/polyester/

Polyester fabric has great properties including its softness and hard wearing nature and unlike cotton does not hold moisture, so is common in sportswear as a ‘wicking’ fabric. For recycling purposes, whilst polyester clothing is recyclable, it is very often combined as a fibre with cotton to produce clothing. Whilst this produces great fabric it does make the recycling a little more complex.

The next largest use for PET is for many drinks bottles because it has a significant benefit over polythene, in that it is a natural barrier to gas transmission. This means where carbonated drinks are to be contained PET is the material of choice. From a recycling point of view since PET bottles are pure PET it provides an excellent raw material, albeit the cap and the label are unlikely to be made from PET.

How is a PET bottle recycled?

PET can be recycled from post-consumer usage. Virtually all local authorities in the UK will accept PET bottles which will be sorted manually from other post-consumer waste. Once sorted the bottles are crushed and baled and sent to a specialist PET recycling centre. One issue can be the use of coloured PET for virgin bottles which ideally need to be separated, adding cost to the process and the industry Trade Body https://www.plasticsrecyclers.eu has lobbied the EU governments to try and discourage beverage companies form using coloured bottles.

The bottles are then washed and shredded into small fragments. At this stage the fragments will contain contaminants form the bottle tops and labels. These are removed by a process called plastic granulation which uses the different densities of the PET versus the contaminants in a wet process to allow separation. The PET will be further purified during the final extrusion process when the molten PET will be passed through a filter.

The use of water for cleansing and separation naturally leaves the PET flake wet and these need to be dried before further processing. PET polymer is very sensitive to hydrolytic degradation, resulting in severe reduction in its molecular weight, thereby adversely affecting its subsequent melt process-ability. The drying is therefore essentially but is does result in a large energy consumption.

Once separated and cleaned the polymer can be used like virgin polymer as the raw material for a new bottle or spun into fibre for clothing use. Typically around 5 PET bottles can be recycled into one T shirt.

So is recycled PET good for the environment?

Globally PET bottles are one of the most recycled plastics with nearly 50% of all PET bottles in Europe being recycled – although rates of PET bottle recycling vary across the world:

GLOBAL RECYCLING RATES

Japan – 92%

Europe – 48%

USA – 29%

India – 90%

Source: https://www.prfire.co.uk/press_releases/global-plastic-bottle-recycling-market-industry-analysis-and-forecast-2020-2027

So what are the benefits of recycled PET:

1.Prevention of ocean bound plastic waste - According to the Ocean Conservancy, ‘8 million metric tons of plastic enter the ocean every year, on top of the estimated 150 million metric tons that currently circulate in marine environments. If we keep this pace, by 2050 there will be more plastic in the ocean than fish. Plastic has been found in 60 percent of all seabirds and 100 percent of all sea turtle species, because they mistake plastic for food’. https://oceanconservancy.org/ - recycling can help stop this.

2.Recycled PET requires less energy to produce than virgin PET - Recycled polyester is almost the same as virgin polyester in terms of quality, but its production requires 59 percent less energy compared to virgin polyester, according to a 2017 study by the Swiss Federal Office for the Environment. WRAP estimates rPET’s production to reduce CO2 emissions by 32 percent in comparison to regular polyester. “If you look at life cycle assessments, rPET scores significantly better than virgin PET.” https://wrap.org.uk/

All good – but like everything in life there is always a counter argument – which is

1.Although the energy required to produce recycled PET is less than that to produce virgin PET fibre, there are even lower energy fibre products such as cotton, hemp and wool. These natural fibres require less energy to produce and as natural fibres will biodegrade. Not that energy alone can be the arbiter – since cotton is criticised for the volume of water and pesticides used in its production and wool for the methane production of sheep (methane being a more intense warming gas than carbon dioxide)

2.Recycling PET bottles can generate other toxins. As discussed above the recycling process involves cleaning and particularly where there is colour involved chlorine based bleaches can be used to remove ink and colourants. These may leach into the environment. There is also a catalyst used in the production of virgin polyester – antimony. Although present in very small quantities the recycling process can release antimony oxide which is a carcinogenic.

3.Micro plastics – whilst recycling keeps those bottles from ending in landfill or being ocean bound, the recycling process will inevitably produce the dreaded micro plastic which is so harmful to marine life. And it is argued that a fibre like cotton can simply remove this as an issue. A paper published in 2011 in the journal Environmental Science Technology found that microfibers made up 85 percent of human-made debris on shorelines around the world. It doesn’t matter if garments are from virgin or recycled polyester, they both contribute to micro-plastics pollution.

CONCLUSION:

Pavilion believes that the best solution to our environmental problems is clarity of information and informed choices. Recycled PET is not a panacea but whilst the drinks industry continues to use around 16 million tonnes of polyester finding a new use and a closed recycling loop has to be of benefit to the environment. If there was way to remove the usage of PET plastic bottles completely, that would clearly be a better option but until there is…………

For further information and discussion please contact davidplatt@paviliongroup.couk

Image fromMatthewdikmans (talk) (Uploads) - Own work, CC BY-SA 3.0, https://en.wikipedia.org/w/index.php?curid=928922

< Older Post Newer Post >

Share this blog:

Raster versus Vector - advice for the decoration of branded promotional merchandise

by David Platt • 5 February 2025

Understanding Vector Files vs Raster Files for Eco Promotional Products When it comes to branding on eco promotional products, understanding the different file types is crucial. Whether you’re creating logos for reusable water bottles or designing training manuals, the choice between vector and raster files significantly impacts the quality, scalability, and versatility of your designs. In this blog, we’ll explore the characteristics of these two file types, their applications, and why choosing the right format matters for both print and digital media. --- What Are Vector Files? Vector files are a digital image format based on mathematical formulas that define shapes, lines, and colours. Unlike raster files, which are made up of pixels, vector files use points and paths, allowing them to remain resolution-independent and infinitely scalable. Common vector file formats include **.SVG** (Scalable Vector Graphics), **.AI** (Adobe Illustrator), and **.EPS** (Encapsulated PostScript). Advantages of Vector Files 1. Scalability: Vector files can be scaled up or down without any loss in quality. Whether you’re designing a logo for a promotional pen or a large conference banner, vector graphics remain crisp and clear. This scalability makes them ideal for **printing on eco promotional products**, signage, and manuals. 2. Editability: Vector files are highly editable. Designers can easily adjust individual elements like shapes, colours, and sizes without compromising image quality. This flexibility is particularly useful for **custom branding**, where logos or designs need modifications for various products. 3. Small File Sizes: Vector files are typically smaller than raster files because they store mathematical data rather than individual pixels. This makes them faster to load, ideal for web use, and easier to share across platforms. Applications of Vector Files Vector files are perfect for projects that require sharp, scalable designs. Their primary uses include: - **Eco promotional products**: Logos for reusable bottles, tote bags, and stationery. - **Print materials**: Brochures, business cards, and training manuals. - **Signage**: Pop-up banners and large-scale graphics. - **Web graphics**: Icons, infographics, and logos for websites. --- What Are Raster Files? Raster files, also called bitmap images, consist of individual pixels that make up the image. These files are resolution-dependent, meaning their quality is determined by the **pixels per inch (PPI)** or **dots per inch (DPI)**. Common raster file formats include **JPEG**, **PNG**, and **TIFF**. Advantages of Raster Files 1. Photorealistic Detail: Raster files excel at capturing detailed and complex images, such as photographs or digital paintings. This makes them ideal for **photographic designs** used in digital or print materials. 2. Image Effects: Raster files support various effects, such as shading, filters, and blurring. These capabilities allow designers to enhance photos or create artistic visuals for **social media posts, eBooks**, or website banners. Applications of Raster Files Raster files are better suited for detailed, photorealistic designs. Their primary uses include: - **eBooks and digital materials**: Low-resolution images for screens. - **Web graphics**: Social media posts and website banners. - **Photography**: Printing high-resolution photos for promotional use. - **Complex artwork**: Digital illustrations or detailed graphics. --- Vector vs Raster Files: Key Differences 1. Scalability - **Vector Files:** Infinitely scalable without loss of quality, ideal for logos and large-format printing. - **Raster Files:** Lose quality and become pixelated when enlarged. 2. Editability - **Vector Files:** Easy to edit individual elements (shapes, colours, etc.), making them versatile for product branding. - **Raster Files:** Difficult to edit without compromising quality. 3. Resolution Dependence - **Vector Files:** Resolution-independent; sharp at any size. - **Raster Files:** Resolution-dependent; quality depends on the original PPI or DPI. 4. File Size - **Vector Files:** Smaller file sizes, suitable for web use and quick loading. - **Raster Files:** Larger file sizes due to pixel data. --- Why File Choice Matters for Eco Promotional Products When creating branded materials for eco promotional products, the right file type ensures your designs are visually appealing and consistent across all platforms. Here’s why: - **For Print:** Vector files are essential. Logos and graphics need to be sharp and scalable for different product sizes, from mugs to banners. Vector files also work best for high-resolution branding on training manuals or reusable promotional items. - **For Digital:** Raster files are better suited for low-resolution displays, such as eBooks, social media posts, and websites. However, remember that even digital logos and icons can benefit from vector files for faster loading and a crisper appearance. --- Partnering with Pavilion Earth for Your Eco Promotional Needs At Pavilion Earth, we understand the importance of getting your branding right, whether it’s for a biodegradable tote bag, a stainless steel water bottle, or digital training materials. Choosing the right file format is just one step in ensuring your promotional products reflect your values and your brand’s quality. Our team can guide you through the process of selecting and preparing the correct file types for your eco promotional products. Need help deciding between vector and raster files? Let us assist you in optimising your designs for maximum impact. Contact Pavilion Earth today to discuss your promotional product needs and branding goals. Together, we’ll make sure your materials stand out while staying eco-conscious.