As an alternative to high-impact polystyrene (HIPS) for medical device packaging applications, Pacur LLChas begun extruding PETG foam made with Eastman Eastalite copolyester. “We believe the industry is looking for a friendlier material replacement for HIPS in terms of cleanliness and the environment,” Jim Banko, Pacur’s vice president of sales, tells PMP News. “Obviously, our focus going forward is full qualifications with medical OEMs.”
Pacur worked with Eastman Chemical Company and thermoformer Tek Pak Inc. to create the new lightweight opaque material. Aneta Clark, market development manager for Eastman Chemical, says that the PETG foam can be thermoformed into any given shape. “Any applications that call for rigid, opaque packaging, including primary trays, can benefit from Eastman Eastalite and its attributes,” she says. “Thanks to its flexibility in design, it’s not just for cushioning. The end application requirements, not the limiting factors of the material, dictate how it’s formed.
Banko explains that “the outer layers of Pacur PETG foam are virgin Eastman Eastar copolyester 6763, providing the same sealing surface as a clear PETG tray. Standard sealing films and papers can be used.”
Adds Clark: “When Eastman developed Eastalite, we used the surface material that is already familiar to the industry: Eastman Eastar copolyester 6763. Testing has already been done, and it’s gone very well.”
In terms of thermoforming, “the material is easy to process and allows for gaining efficiencies through optimization of process conditions,” she continues. “Eastman Eastalite also can be cut and trimmed without generating lots of particulates and angel hair, unlike HIPS. Cleanliness makes PETG foam more efficient.”
Banko explains that the PETG foam has a density of 0.80 gram per cubic centimeter and is 20 percent lighter than HIPS. “As far as gauge, shrinkage, and toughness, PETG foam can be directly run on existing HIPS molds at the same gauge and attain similar shrinkage and improved impact resistance.”
Adds Tony Beyer, owner, Tek Pak: “Pacur PETG foam was easy to work with and has many qualities we value as a thermoformer. We were able to run the machine faster with the Pacur PETG foam than with an equivalent polystyrene material. We also found it to be cleaner when looking at angel hair and particulate generation. The material is easily trimmed and removed from the forming machine and has a beautiful pearlescent look. Overall, it’s an upscale material that has unique properties compared to other materials in the market.”
Clark expects original equipment manufacturers to find value in the material’s cleanliness. “As with Eastalite, there is a significant reduction in surface particulates as well as no requirement for the use of denesting agent,” she says. “Also, the unique design freedom allows for features such as durable life hinges, snap fits, and deep draws to be incorporated into the package design. This allows the final product to have a functional aspect.”
And “because of its foamed core, the same design uses less material, and the overall package is lighter,” she says.
Despite that light weight, the material is shock-absorbent for impact resistance during shipping, Eastman Chemical reports. Eastalite also can provide greater tear strength while retaining color stability and functional integrity following sterilization by ethylene oxide (EtO) or gamma irradiation. The Eastalite copolyester foam “can be easily sterilized via gamma irradiation, ethylene oxide (EtO), e-beam, and gas plasma, all without compromising its functional integrity and without discoloration,” says Clark. “It’s quite versatile. It can be sterilized many different ways without compromising functional integrity or changing the color.”
Containers can be thermoformed with deep undercuts and durable living hinges, and they exhibit less stress whitening than packaging molded from HIPS, Eastman reports.
When asked what challenges companies face when switching from HIPS to the PETG foam, Clark says they mostly center around the qualification and validation process. “It can be a lengthy and costly process. The good thing is Eastman Chemical Company already has compiled a significant body of work to assess the performance of the material [and] its compatibility with ISO 10993 and select ISO 11607 standards. This can help save time and money. Also, we have a team of experts on hand, both technical and regulatory, to help customers through the qualification process. Given that many customers will have unique requirements for their applications, our team often collaborates on a case-by-case basis to generate additional data as needed. Eastman has been in this business for a long time, and we understand there are different requirements. Our team is willing to work one-on-one with clients.”
Eastman reports that Eastman Eastalite is made without materials of concern, including butadiene, bisphenol A, bisphenol S, ortho-phthalates or halogens such as chlorine or bromine. The material is compliant with ISO 10993 requirements for medical device biocompatibility and applicable parts of ISO 11607.