Healthcare mega trends, notably the drive to improve patient safety and shifting patient care from hospitals to the home, bode well for the continued growth of plastics in the medical space, noted Niya Petzold, Healthcare Marketing Manager for Borealis (Vienna), during a recent webinar. Plastics are the obvious choice as “industry looks to safer and lighter solutions,” said Petzold. She illustrated this dynamic with two recent applications where a “new class of soft polypropylene” achieved "breakthroughs" in the manufacture of IV bottles and bags.
“Only about 1% of the 311 million tons of plastics, or about 3.1 million tons, go into healthcare,” said Petzold. And yet, medical plastics get an awful lot of attention. They punch above their weight because they are subject to “the highest quality requirements and most stringent regulations. Yes, it’s a tiny market,” said Petzold, “but it has been a large focus for Borealis.”
Borealis is one of the largest polyolefin producers in the world, reporting $7.2 billion in sales in 2016. While the medical space is a small part of the company’s overall business, medical applications for polyolefin have been growing over the past few years, according to Petzold. The reason, she added, is because it achieves a desirable balance in performance and cost and enables a breadth of new design opportunities. During the webinar, Petzold highlighted two recent medtech “breakthroughs” that were made possible by Borealis’ medical-grade soft polypropylene, marketed under the Bormed name.
Bormed SB815MO was developed for blow-fill-seal applications, such as IV bottles and ampoules in the medical space. “The material of choice has been LDPE,” said Petzold, which has all the requisite properties for this application—softness, transparency and processability—save one: “The material must be sterilized at low temperatures and, thus, requires longer sterilization cycles.” Random PP co-polymer has also been used, and while it withstands high sterilization temperatures, it also exhibits high stiffness. “So you will have the problem of not being able to empty all of the IV liquid from the bottle or ampoule,” said Petzold. The solution developed by Borealis combines the properties of both materials: Bormed SB815MO is as soft as LDPE and can be sterilized at 121° C, thus allowing short sterilization cycles, and its transparency matches random PP co-polymers.
Bormed SC876CF was developed for complexly structured primary and secondary IV packaging, where each layer has its own functionality. Petzold illustrated the level of complexity in a three-layer film:
- The 20-micron outer layer, made of homo or random PP, must be heat resistant;
- the 130- to 160-micron core layer of soft or random PP must be soft and tough; and
- the 30- to 50-micron sealing layer, random PP or terpolymer, must be transparent and sealable.
All of the layers must withstand sterilization and retain transparency. All of them also may contain impact modifiers to a lesser or greater extent, which pouch producers often require to deliver toughness and softness, especially in the core layer. Impact modifiers are pricey, and “one way that pouch producers can reduce cost is by reducing the quantity of impact modifiers,” explained Petzold.
By using Bormed SC876CF