Polypropylene

The main environmental consideration—along with all other synthetics in this category—is that this material, whether in fibre form or other, is non-biodegradable and intended for short-term usage. Global polypropylene usage is at 2.6 million tonnes, and efforts to address sustainability innovations could make a significant impact on the industry and the planet.[1] Polypropylene (PP) is a long-chain synthetic polymer composed of at least 85% by weight of ethylene, propylene or other olefin units. Polypropylene is a manufactured and man made polyolefin fibre and used in a number diverse applications ranging from carpet to technical and outdoor apparel to geotextiles and product packaging.

Polypropylene’s characteristics have been perfected over the years since it was originally developed in the 1950s. It has excellent durability, strength and resiliency while still being lightweight. Polypropylene has good resistance to ultraviolet degradation, stains and spilling, and excellent wicking action—which make this material great for carpets.[2] These features also eliminate the need for water and stain-repellent finishes. Polypropylene’s natural buoyancy also makes it perfect for high performance apparel such as wetsuits and swimsuits. Polypropylene blends well with other fibres, and when used capitalizes on its excellent wicking properties.[2] No dyeing is necessary—which means no pollution from dyeing— since colours are incorporated during the fibre-forming stage.[3] Its low softening point encourages consumers to launder their products in low temperature washing and ironing, thereby minimizing water and energy use associated with consumer care and washing.[4]

Processing

Typical of synthetic fibres, production for polypropylene varies amongst manufacturers. Individual manufacturers have variations in their processes to achieve certain properties such as dyeability, light stability and heat sensitivity.[5] The manufacturing process for polypropylene requires non-renewable resources and high water and energy use.[6][7][8] Fuel released by vehicles used to transport oil and waste causes pollution and CO2 emissions. [9]

End of use

Polypropylene’s most substantial environmental impact is at its End of Use stage. Polypropylene is non-biodegradable, and polypropylene products increase load on landfills and end up in oceans and large bodies of water, where they can harm aquatic species and potentially end up back in our food and water. According to a study done by Mark Browne, an ecologist at University College Dublin, microscopic fragments of acrylic, polyethylene, polypropylene, polyamide and polyester have been discovered in increasing quantities across the northeast Atlantic, as well as on beaches in Britain, Singapore and India.[10][11]

Recycled polypropylene

Using recycled polypropylene achieves two main ecological benefits: 1) it slows the depletion of virgin natural resources, and 2) it reduces textile waste building in landfills. Polypropylene can be recycled into new versions of the same product or into entirely different products. Post-consumer waste from used and discarded products and post-industrial waste from material collected during the product manufacturing can be recycled.

Mechanical recycling

Polypropylene can be effectively collected, cleaned, cut, re-melted and remolded. However, the material is “downcycled” in this manner, which means that its physical structure breaks down, and eventually the product must be discarded to landfill. Infrastructure for collection, sorting and purifying must be in place. Note: recycled polypropylene still uses significant amounts of energy throughout the production process.

Recycled polypropylene is available from suppliers in Europe and China. Bio-derived polypropylene is currently an advancing technology and is not readily available.

Recycled polypropylene is available from suppliers in Europe and China. Bio-derived polypropylene is currently an advancing technology and is not readily available.

• Promote the use of recycled polypropylene.

• Promote the research of bio-derived polypropylene. Bio-derived polypropylene is derived from renewable resources, such as sugar cane. Bio-plastics have a lower carbon footprint, and some are recyclable and compostable. There is no guarantee that they are manufactured with less harmful chemicals or contain fewer toxic additives. Also, plants used for bio-plastic feedstock can be grown without fertilizers and pesticides.[12][13][14]

• Promote OEKO-TEK certified polypropylene.[15] OEKO-TEK is an independent, third party certifier that offers two certifications for textiles: OEKO-TEK 100 (for products) and OEKO-TEK 1000 (for production sites/factories). OEKO-TEK 100 label aims to ensure that products pose no risk to health. OEKO-TEK certified products do not contain allergenic dye-stuffs and dye-stuffs that form carcinogenic aryl-amines. The certification process includes thorough testing for a long list of chemicals. Specifically banned are: AZO dyes, carcinogenic and allergy-inducing dyes, pesticides, chlorinated phenols, extractable heavy metals, emissions of volatile components, and more.

X% Recycled Content Regulations require stating percent recycled if not 100% recycled content.

XX% bio-based If verified and used.

1. At the product design stage, consider what will happen to a polypropylene product at the End of Use stage of the lifecycle. Design products that address longevity, recyclability, biodegradability, disassembly for reuse, etc.

2. Work with partners to develop closed loop recycling of polypropylene products and infrastructure to collect and sort.

3. Look to suitable fibre alternatives for polypropylene that have more advanced technology and infrastructure for recycling and biodegradability, such as polyester and polylactide (PLA).

4. Work with suppliers to advance technology for bio-based plastics from organic feedstock.

5. Design polypropylene products with reuse in mind in order to optimize resources embodied in the product.

6. Get your product Cradle to Cradle Certified. The Cradle to Cradle CertifiedTM Product Standard is a multi-attribute, continuous improvement methodology that provides a path to manufacturing healthy and sustainable products. The Standard rewards achievement in five categories and at five levels of certification. An accredited assessor will help to assess and optimize your product.

1. Oerlikon. (2010) The Fibre Year 2009/2010. A World Survey on Textile and nonwovens Industry. Retrieved from http://www.indotextiles.com/download/Fibre%20Year%202009_10.pdf
2. Freinkel, Susan. PLASTIC A Toxic Love Story. New York: Houghton Mifflin Harcourt, 2011.
3. https://www.fabriclink.com/university/polyolefin.cfm
4. https://www.engr.utk.edu/~mse/Textiles/Nylon%20fibres.htm
5. Corbman, Dr. Bernard P. Textiles: Fibre to Fabric. New York: McGraw Hill Book Company, 1975.
6. https://www.plasticseurope.org/Documents/Document/20100312112214-FINAL_HDPE_280409-20081215-017-EN-v1.pdf
7. EPA. (1991) Chapter 6: Organic Chemical Process Industry retrieved from:
8. https://www.epa.gov/ttnchie1/ap42/ch06/
9. https://www.tech.plym.ac.uk/sme/mats324/mats324A9%20NFETE.htm
10. https://www.epa.gov/climatechange/wycd/waste/downloads/plastics-chapter10-28-10.pdf
11. https://www.ecouterre.com/is-synthetic-clothing-causing-microplastic-pollution-in-oceans-worldwide/
12. The Textile Dyer, “Concern over Recycled Polyester,” May 13, 2008.
13. https://www.prweb.com/releases/2012/2/prweb9194258.htm
14. biopol.free.fr/index.php/to-make-green-polypropylene-from-sugarcane/
15. news.discovery.com/earth/plants/bioplastic-plant-plastic-environment.htm
16. https://www.OEKO-TEK.com/media/downloads/Factsheet_OETS_100_EN.pdf