Although injection molding has been in use for over a century, the materials and machinery manufacturers crowding the exposition hall at MD&M West 2018 continue to demonstrate new developments that will keep the technology at the heart of the medical products industry well into the 21st century. One those exhibitors, Covestro LLC, a global manufacturer of polymer materials, is demonstrating several new materials, along with some of the applications they made possible. The company is also sharing the results of some of its experiments with an innovative molding process
New Products, New Applications
Covestro introduced Makrolon® Rx3440 polycarbonate to the Makrolon material family. Designed for use in IV components, Rx3440 provides superior chemical and oncology drug resistance to help prevent cracking. The formulation also offers superior heat resistance and impact strength, retaining its properties at elevated temperatures that may cause other plastic materials to degrade over time.
Two of its other plastics play leading roles in a disposable on-body delivery device from Enable Injections, Inc. that allows patients to comfortably self-administer high volume and/or high viscosity therapeutics. Components of the Enable device are injection molded with Makrolon® Rx1805 polycarbonate and Bayblend® M850 XF PC+ABS blend.
The Enable enFuse, which uses Covestro’s Makrolon® polycarbonate, provides a controlled and comfortable flow of drug at a rate that adapts to the user. Credit: Enable Injections
Besides minimizing discomfort and improving patient compliance, the Enable device is available as a “smart” device that communicates its dosage history to a Smartphone or IoT portal via a secuire low power wireless link. For more information, visit http://www.enableinjections.com/.
Teaching an Old Process New Tricks
Covestro is also sharing the results of some recent research into a process that can improve the surface finish quality of molded plastic components while reducing manufacturing costs. Intended primarily for polycarbonates and polycarbonate acrylonitrile butadiene styrene (PC+ABS) blends the process is based on an emerging technology known as rapid heating and cooling molding (RHCM).
According to Jessica Boyer, application development engineer at Covestro, conventional molding techniques often cause the surface of the injected molten plastic to harden before it can fully conform to the mold. The RHCM process avoids this by superheating the mold surface before the plastic is injected into the mold. Once the cavity is filled, the mold is cooled rapidly during the packing and cooling phases before the part is ejected.
In addition to improving the finish quality, the process offers shorter cycle times and a greater control over surface properties. “The RHCM process allows for designers and molders to control the gloss level through different textures and polishes by adjusting the mold temperature used during the injection molding process” explains Boyer.
A longer technical article that provides the details of Covestro’s work with RHCM and its potential for medical applications is available by clicking here.