Coffee capsules & pods
Coffee capsules & pods Bio-PBS to increase benefits of PLA coffee capsules BIO PBS Flexible Higher Faster Translucent Higher Lower Lower By: Fabien Resweber & Pissapak Srihaphan PTT MCC Biochem Company Limited Bangkok, Thailand Flexibility Impact strength Biodegradability Heat resistance Process temp. Heat-seal temp. Transparency Rigid Lower Slower Lower Higher Higher PLA Transparent The coffee capsules sold by one major brand in 2013 alone created enough waste to encircle the earth more than ten times. The high fraction of water and coffee grounds makes them difficult to incinerate or recycle, a problem that could easily be circumvented by using compostable capsules based on BioPBS. The benefits of BioPBS were introduced during a presentation at two separate Single Serve Capsules conferences, one last year in Berlin, the other this year in Chicago, in which the outstanding compostability of this material was highlighted. BioPBS reduces cycle time while increasing HDT and Izod Impact strength One key benefit of blending BioPBS with PLA for injection moulding is that the degree of crystallinity of the matrix increases. PLA is an amorphous material with a very long cooling time. Adding BioPBS can therefore significantly shorten its cycle time. In a PLA blend with 20% BioPBS, the crystallization process is accelerated, reaching a percentage of crystallinity of 50 %; in a 40/60 blend of BioPBS/PLA a peak level of 80 % can be reached. Cycle time can be cut in half compared to cPLA , without compromising capsule mould productivity. Increasing the BioPBS content to 60 % or higher also improves the thermal properties of PLA, allowing the HDT A (0.45 MPa) value to be increased to almost 100 °C. As a result, BioPBS-based capsules will not twist or lose their shape during use, nor clog up the coffee machine. Increasing the BioPBS ratio from 20 to 40 has the additional advantage of improving the Izod impact strength of the material. Even better results are achieved if a 60/40 blend of BioPBS/PLA is used. Basically, the more BioPBS that is added, the more flexibility that can be expected from the compound. On the other hand, the PLA component increases the biobased content and adds solidity to the cap body. BioPBS meets new challenges for coffee capsules Previously, compostable coffee capsules had a limited oxygen barrier and required secondary packaging for wrapping. New solutions for compostable oxygen barriers now exist for all coffee capsule designs, decreasing the total amount of packaging needed. Barrier solutions mainly include the use of compostable IML (In-Mould-Labelling) or a compostable barrier layer injection molded in a co-injection process, and are perfectly compatible with BioPBS-based compostable capsules. In countries or cities where organic waste is collected, fully compostable capsules can be included in that composting stream, increasing the amount of waste being recycled through this organic recycling process. However, since industrial composting facilities are not yet accessible worldwide, there is now a strong market demand for a coffee capsule that will biodegrade in a home composting environment at ambient temperatures. BioPBS offers a way to make this possible, as this material provides a fast degrading polymer matrix, even at ambient temperature. BioPBS is increasingly gaining acceptance and is used as the raw material in various global sustainable coffee capsule brands for injection moulded and mesh parts. Total solution for compostable coffee capsules BioPBS can be applied in all the various parts of the coffee capsule, depending on the grade used. BioPBS lidding film (BioPBS sealant + barrier cellulose) provides an excellent oxygen barrier; BioPBS body or cap offers flexibility, heat resistance, and reduced cycle time. Finally, BioPBS can be used in a mesh (nonwoven filter) part on the bottom of the capsule to retain the ground coffee. The burgeoning popularity of single serve coffee capsules is cause for concern, as their use generates a vast amount of waste. Changing to a BioPBS capsule could definitely help solve this waste problem. Environmental benefits Formulating a coffee capsule material with a high BioPBS content can contribute to the reduction of non-recyclable waste and decrease the impact on the environment. Capsules made with BioPBS can be treated as organic waste, which means they can be disposed of in the organic waste bin (where available and permitted) without separating them from the coffee grounds. In applications like this, where it is impossible to re-use or recycle, compostable materials definitely contribute to cleaner end-of-life options and lower disposal costs. www.pttmcc.com 40 bioplastics MAGAZINE [04/18] Vol. 13
Coffee capsules & pods PürPod100 In 2015 Club Coffee, Toronto, Ontario, Canada, introduced PürPod100, what was, as stated by the company, the world’s first 100 % compostable, fully certified singleserve pod. “The amount of used single-serve pods sent into the waste stream last year could have circled the earth eleven times. That’s not acceptable,” said John Pigott, CEO, Club Coffee. “We have the most viable solution available to that issue – a pod that will be certified as 100 % compostable and can be converted to useful compost.” “As a large manufacturer and distributor of packaged coffee, we have a responsibility to our customers, and to society, to reduce the environmental impact of our activities.” The PürPod100 is made from renewable, biobased materials (more details were not disclosed) that are 100 % compostable, and the ring of the pod is made using coffee chaff – the skin of the coffee bean that comes off during the roasting process. Every single part of the PürPod100 is designed to be digestible by, and accessible for, bacteria. The PürPod100 is compatible with most Keurig brewing systems, including the new Keurig 2.0 brewers. “Still, plastic (and aluminium – MT), single serve coffee pods are included in this disposable waste stream. Where curbside food scrap collection programs exist, certified compostable products have the ability to help increase waste diversion while reducing contamination in the finished compost,” said Al Rattie, Director of Market Development, US Composting Council. “We hope that companies like Club Coffee will continue to work with the USCC to not only develop products that are tools for diversion, but also help support the growth of the food scrap collection and processing infrastructure needed to close the loop on products like compostable coffee pods. The resulting production and land application of high quality compost is essential for the creation of healthy soils and a sustainable society.” The PürPod100 was developed in conjunction with international experts and scientists at the University of Guelph. “Science shows that composting is an effective and conscientious solution to this growing environmental problem”, added Pigott. “Recycling isn’t a convenient or welldeveloped solution because hot pods full of coffee grounds must be carefully separated and cleaned before collection.” Steve Mojo, then executive director of the certifying body BPI, said, “Club Coffee’s () pods represent a significant improvement in single-serve coffee. Everyone involved in this technological advancement are commended for their hard work. All BPI approved products meet ASTM D6400 or ASTM D6868 based on independent lab testing, whose results are verified by NSF International.” In the meantime Club Coffee received certification for the PürPod 100 products.MT www.clubcoffee.ca RING Made with coffee bean skins and other compostable materials LID Made with paper and other compostable materials FILTER Made with plant-based materials bioplastics MAGAZINE [04/18] Vol. 13 41
