Add Parker Hannifin to the companies that are innovating when it comes to medical-grade polyurethane tubing.
The Cleveland–based company in recent years developed what it touts as a unique aliphatic polycarbonate polyurethane with expanded and enhanced chemical compatibility, particularly in basic applications. It is resistant to damage oxidation and alcohol absorption, and also has expanded resistance to environmental stress cracking.
|Arlo McGinn, PhD|
“Whether it’s cleaning agents, acids or bases, our polymer is shown to have the best all around compatibility,” says Arlo McGinn, PhD, a senior chemist at Parker Hannifin specializing in medical urethanes.
The polyurethane was initially developed for an undisclosed OEM that wanted a material for a drainage catheter that would hold up better and avoid material swelling as health practitioners swabbed isopropyl alcohol around it, McGinn says. The extensive chemical resistance of the Parker Hannifin material allows for confident exposure to any number of biological fluids while also providing resistance to commonly used alcohol cleaning agents.
The OEM was among many medical device companies that are discovering that some types of polyurethanes have desirable characteristics such as good bio- and hemo-compatibility, plasticizer-free formulations, and availability in a broad range of durometers.
McGinn explained how the manufacturing process plays an important role when it comes to producing the aliphatic polycarbonate polyurethane:
“We may do it a little bit different from some other competitors out there who create polymer batches on a large, reaction extrusion scale. But the differences in our synthesis process contribute to creation of a polymer that’s more consistent batch to batch. This batch to batch uniformity is manifested by tighter melt flow indices and repeatedly reliable broad chemical resistance. You know the material you get from us today is going to perform and process in a very similar manner as the next lot that you order from us.”
The move to polyurethanes is also enabling more sophisticated tubing designs in the extrusion process, including complex cross-sections with multiple lumens (more than one hole) and thinner walls than allowed by other commodity polymers.
Polyurethanes are additionally important because they are providing an alternative to flexible PVC. Use of PVC in such medical applications as IV bags and tubing has diminished because it incorporates potentially toxic phthalate plasticizers such as DEHP.
Providing custom miniature tubing with an inner diameter as small as as 0.1 mm and a wall thickness of approximately 0.05 mm, Raumedic manufactures microextruded tubing that is suitable for use in microfluidic and microcatheter applications. The company’s extruded tubing is employed in paediatric and microanalytic devices, as well as peripheral infusion cannulae.
Dunn Industries produces custom tubing for the medical device market. The company’s custom tubing includes solid-rod, single-lumen, multilumen, coextrusion, and several other formats. Manufacturing medical-grade tubing from a range of engineering thermoplastics such as acetal, Pebax, Isoplast, Hytrel, Tecoflex, polysulfone, LDPE, LLDPE, PETG, and custom compounds, the contract supplier offers tubing with outer diameters as small as 0.010 in. and inner diameters down to 0.005 in.
Dunn Industries Inc.
A trilayer extrusion process offered by Interface Catheter Solutions produces tubing with an outer layer, a core layer, and an intermediate tie layer that prevents delamination. The low-friction, three-layer tubing allows a guidewire or catheter to be advanced through the lumen without compromising strength or stiffness. The extrusion process is guided by an imaging system that captures high-resolution pictures of the cross section of the extruded microtubes. This process ensures that the tie-layer is circumferentially present throughout the length of the extrusion. Produced in cleanroom facilities, the company’s custom close-tolerance tri-layer extrusions can be supplied with wall thicknesses up to 0.0023 in. In addition to offering trilayer tubing, the company specializes in the manufacture of single-lumen, multilumen, striping, bump, and lead tubing.
Interface Catheter Solutions
Laguna Niguel, CA
Featuring high lubricity, transparency, and chemical resistance, heat-shrink tubing from Optinova is available with an antistick surface. Known as FEP QuickShrink 2.0, the tubing has a low and adjustable shrink temperature between 80° and 170°C. This tubing offers rapid shrinking capability, high chemical resistance, and low gas permeability and allows high transmission of ultraviolet rays. Certified according to ISO 13485:2003 standards and operating under CGMP guidelines, the company offers tubing that can be sterilized using gamma, EtO, E-beam, and autoclave methods.
Polyurethane and Pebax tubing
Offering proprietary medical-grade polyurethane and Pebax tubing, Parker Hannifin Corp. manufactures tubing that meets stringent performance, biocompatibility, and sterilization requirements. The company’s aliphatic polycarbonate-based polyurethanes are high-purity, nonyellowing materials that feature high chemical resistance and biodurability. The tubing may be compounded with custom colorants and radiopaque fillers. Providing biocompatibility, steriliziability, and good mechanical properties, the company’s polyether block amide (Pebax) tubing line features kink resistance and high torque transference. It can be compounded with radiopaque fillers and coextruded with polyurethane.
Parker Hannifin–Engineered Polymer Systems Div.
Salt Lake City
Published in MPMN, March/April 2014, Volume 30, No. 2
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