This post was written by Injection Molding Segment Lead – Craig Crossley
If you were at any of the major plastics trade shows this year you would have noticed a key theme present was the Circular Economy, sustainability recycling, green manufacturing, etc. Every major brand around the world is putting money and effort into making their products greener and making their packaging less impactful on the environment. One large question with all of this change is how can you prototype quickly with the same material that will be used in the production process?
Sustainable materials are used throughout our consumer and industrial economy that can be produced in required volumes without depleting non-renewable resources and disrupting the established steady-state equilibrium of the environment and key natural resource systems.
Sustainable materials can come in a few different forms, all of which have unique advantages and disadvantages. Bio-plastics are generally derived from renewable resources or they are resins that are biodegradable like PLA. Along with bio-plastics, there is Post Consumer Recycled (PCR) resin, scrap regrind, and reclaimed plastics, all of which will play a huge part in reducing plastic waste and making better use of existing resources.
A 3D printed injection mold from Fortify made from sustainable materials
Some examples of sustainable materials include:
Consumer Packaged Goods is an industry term that describes products that consumers will use up and need to replace. These can come in a variety of different products like beverages, toys, and makeup, with more examples below.
Some examples of consumer packaged goods include:
Manufacturers across the globe are feeling pressure from consumers, governments, and leading brands to become more eco-friendly and start using sustainable materials. These materials can help to reduce the amount of plastic waste, as well as reuse materials that are perfectly capable of having new life. Although plastic does make up a very small portion of overall waste, every bit helps keep the planet healthy. Utilizing these types of materials is a foregone conclusion that brands and governments are clamoring for, so the manufacturers who are set up to act quickly and assist in the changeover to these resins are going to be the ones who are successful.
As every product engineer and process engineer knows, when you change the material the part design and the production process must change with it. It is not as simple as taking a polypropylene part, switching it over to low-density PCR resin, and calling it a day. You must prototype and change the part design in order to get the same functionality, you have to alter the tooling in order to create the same quality part, and overall you need to produce prototypes to make sure it performs as expected.
However, there are going to be some inherent performance disadvantages when it comes to increasing the heat history of a polymer as every time the polymer is remelted the molecular weight is decreasing, which in turn reduces its mechanical properties. This does not mean that they can not be reused or are useless, it just means that the amount of thought, prototyping, and iteration on design needs to be taken seriously in order to properly utilize the current resources we have.
PCR Resin can come in a few different forms and it is imperative that if you are going to use it, it comes from a reliable source. Erema Group is a leader in the recycling equipment industry and provided some insight on some reliable PCR providers in last year’s Earth Day blog: Recycled Materials and Recycling Technologies: How to Incorporate Both into Your Prototyping Process.
Knowing what PCR resin you are getting is key to utilizing it properly. It can be split up into a few categories including low-density PCR Resin, high-density PCR resin, and then specific resins gathered from a single source material. (For the purposes of this blog, those materials have been split off into their own category, “Reclaimed resin”). Making sure you know which category of PCR resin and the reliability of the supplier can allow manufacturers and product developers to produce more sustainable products that do not disappoint.
Scrap regrind
Scrap regrind is one of the easiest ways that manufacturers can help to reduce their waste, but they need help from the leading brands in order to do so. Allowable regrind is on the bottom of every process setup sheet, yet many of these are left at 0% meaning that whoever the customer is, will not allow the manufacturer to use any regrind in their product. This can be for a variety of reasons including contamination, material performance, or others, but allowing for more regrind or putting an emphasis on bringing in recycling equipment to create better quality scrap regrind, could result in 0 waste factories where all out-of-spec parts, sprues, and runners are repurposed.
Bioplastic made from Cornstarch
Bioplastics are one of the most innovative and exciting developments going on in the industry today. These biodegradable resins could completely change the packaging market forever if they can be properly utilized. Materials like PLA, PHA, and others are biodegradable and can be derived from renewable resources, both of which are great for the future of the environment, however, they are not the perfect solution for every application. It is up to product development and innovation teams to work with these materials to find out where they best fit and where they do not. Companies like Radical Plastics, Avient, Covestro, and others are constantly working on new biodegradable materials in order to contribute to the circular economy and promote sustainability.
Reclaimed Plastics are a subsection of PCR resin that is derived from a single source like the company Fishy Filaments does with their nylon material gathered from old fishing nets. Generally, these materials are of higher quality than your standard PCR as they are the same polymer, often the same or very similar grades. Bottle-to-bottle PET or HDPE is very similar in that way, where the source material is coming from a known polymer, instead of a possible blend of several polymers.
Due to this, the mechanical properties and the quality of the material is superior and can be used for more applications. The recycled material is not going to be the same as the virgin plastic it comes from, but the performance drop-off for many thermoplastics can be mitigated by proper recycling practices, high-quality equipment, and the reduction of contamination.
This type of recycled material is likely the best for most higher-value applications, but with that, comes a higher demand and higher price for it. It is more difficult to get plastics recycled all from the same material as the current infrastructure does not have separate streams for all of the different polymers that are used. With that said, reclaimed/recycled plastics are a great way to reduce waste in the consumer goods industry and the packaging industry.
A 3D Printed Mold Tool from Fortify
Fortify’s injection molds are ready in a few days and provide cost savings of up to 70%. Get a quote for low-volume injection molded parts in high-performance plastics such as PEEK, Ultem, and PSU from Fortify to see how much you can save.
Want to learn more? Request a review with Fortify’s Injection Molding team to learn more about developing your product with a more sustainable material, without sacrificing quality and performance.