A Scientific & Eco-Friendly Approach to Plastics Manufacturing

 <br>Scott Schoenborn

Scott Schoenborn

General Manager, Turtle Lake Facility, Sanmina

Plastics are an integral part of products we use every day, whether it’s the case that protects your mobile phone, the automotive parts that make your car lighter and more energy efficient, or the sterile instruments used in your doctor’s office. Consumer, medical and industrial companies all greatly rely on plastic to make their products work.

Sanmina’s manufacturing facility in Turtle Lake, Wisconsin was renovated in 2016 to focus on precision plastic injection molding services, due to the need for high-performance, lightweight and low-cost plastic parts. Along with products like cell phone accessories designed for the consumer market, the site also develops plastic parts used in operating rooms, medical consoles and innovative surgical items. For the industrial market, we make plastic parts for products like data communication devices.

We have a broad range of plastic presses and processing capabilities at the plant that enable us to specialize in a wide variety of plastics. This includes polypropylene, a cost effective plastic for things like automotive parts and consumer packaging, all the way through to higher thermal plastics such as PEEK (Polyetheretherketone), used in more demanding aerospace, automotive, electrical and medical applications.

Ultimately, it’s up to the plastics industry and society to work together and come up with ways to intelligently utilize the earth’s resources.

-SCOtt schoenborn

Six years ago, the site transitioned from a conventional plastic molding process to an engineering focused approach known as scientific molding, to enable repeatable and consistent parts manufacturing. This involves using a combination of engineering resources to select the proper resin, design tools and processes that ensure a high quality product, from start to finish. Equally as important, transitioning to a scientific molding approach enabled us to further prioritize more eco-friendly aspects of producing and repurposing plastics.

Environmental Trends

We all know that plastics can harm the environment. This impact, however, also applies to the manufacturing of many other materials, such as wood or glass, that aren’t suitable for many products because of their weight or lack of energy efficiency. When determining the right material for a product, organizations must consider the whole picture, not just how the product is produced but how it’s used and its potential for reuse.

From a scientific standpoint, plastics processing starts with a material that contains very long molecular chains. The key is to retain the length of the molecular chains throughout processing, so that the plastic has more chemical and mechanical integrity in the final product. Some manufacturers that don’t use scientific molding may produce a product faster at higher heat, breaking down the molecular chain into multiple, shorter chains. In the end, the final product has less integrity and isn’t ideal for reuse.

Many medical components and cell phone cases require plastic injection molding.

Our customers are increasingly embracing new ways to build their products, using alternative approaches and more eco-friendly practices, including:

Bio-based plastics. An innovative example of a bio-based plastic product is a termite trap that includes wood fiber in the plastic parts. As the termites eat through the cellulose, it triggers a signal to tell the home owner that they have a termite problem. Currently, green bio-based plastics are being developed on an as-needed basis, making them expensive at two to four times the rate, compared to traditional resin. But for many of our customers, it’s not about pricing as much as it is about reducing their carbon footprint and long term environmental impact. As more companies head in this direction, the overall costs for these plastics will eventually decrease.

Repurposed plastics. Repurposed plastics are another growing market. While the industry has been regrinding and reusing plastics for decades, new methods utilize this approach at a much broader scale. This involves taking plastics from end-of-life consumer or industrial products and applying robust processes to introduce plastic back into a usable product, at scale and with a predictable output. We recently conducted a reuse study for a product made of polycarbonate. After regrinding 100 percent of the plastic, we compared it to the original product and it met 90 percent of the mechanical requirements. Now the customer has a brand new market for a great product that is eco-friendly and appeals to environmentally-conscious consumers.

Virgin vs. recycled plastics. Organizations are also focusing more attention on when to use recycled plastics instead of virgin plastics in their products. While certain products warrant a virgin plastic due to quality and engineering requirements, a lot of products can be made from repurposed materials. Good examples of items that are ideal for reused plastics are products like toothbrushes or disposable eating utensils.

Resin selection is based on strength, flexibility or rigidity, environmental/chemical resistance, life expectancy, appearance in the final product and the ability to meet several regulatory requirements.

Intelligent Use of Resources

While some groups are pushing for the complete elimination of plastics, the focus should really be on how to efficiently produce and reuse plastics. Plastics are integral to modern society and benefit us in many ways. It’s hard to image during a major event like the pandemic, how we would have fared without plastics to support products like heart or oxygen monitors, ventilators, disposable COVID test kits and face masks.

The durability and quality of plastic makes it an invaluable material for many products and can it be reused at higher rates than many other materials. In addition to ambitious environmental and financial KPIs that companies must comply with in many countries, consumer recycling programs are vital to environmental stewardship and are dependent on every individual doing their part. Ultimately, it’s up to the plastics industry and society to work together and come up with ways to intelligently utilize the earth’s resources.