Strength of TPE Medical Tubing Assembly with Single-Barb Fitting Surpasses That of Standard Adhesive-Bonded PVC
Teknor Apex Co.
505 Central Ave.
Pawtucket, RI, 02861
Press release date: April 2, 2014
In Tests by Eldon James Corp. of Tubing Made with Medalist® TPE from Teknor Apex, Connection Withstood More than Double the Force Specified in Customer Requirements
DENVER, CO, U.S.A. – Tests by Eldon James Corporation, a manufacturer and custom assembler of medical tubing and fittings, have demonstrated the toughness of tubing produced from Medalist® thermoplastic elastomers (TPEs), and the durability of connections between this tubing and single-barb luer fittings, it was announced today by Teknor Apex Company.
Teknor Apex, which manufactures the Medalist range of medical elastomers, will present the results of the tests at its exhibit during MD&M East (Booth 1551), along with sample kits provided by Eldon James.
In pull-apart tests of more than 1,000 assemblies, the connections typically did not fail until forces greater than 8 lb. were applied—more than double the requirement set by Eldon James' customer, according to Mark Timbrook, director of marketing. In burst tests, the TPE tubing withstood average pressures of 500 psi before failure (see table).
"The elasticity of the TPE has proved to be an advantage in two ways," said Mr. Timbrook. "It enhances the bond between tubing and fitting, in much the same way that the grip of a finger-trap toy tightens as you pull your fingers outward. At the same time, within the parameters of our burst test, the resilience of the TPE prevents the tubing from rupturing. While PVC tubing would burst under similar pressures, the failure of the TPE tubing took the form of bulging."
Seeking an alternative from PVC tubing as well as from the adhesives typically used for bonding it with connectors, Eldon James produced a new range of tubing from Teknor Apex's Medalist MD-585 compound and paired it with USP Class VI-compliant single-barb connectors, which it also manufactures. "We've found that single-barb fittings make a better seal with TPE tubing than multi-barb connectors, one that is at least comparable in strength to that of adhesive assemblies with PVC tubing," Mr. Timbrook said.
While exceeding customer requirements based on adhesive-bonded fittings, single-barb fittings save time and cost in comparison with adhesive assembly, according to Eldon James, while avoiding issues involving volatile organic compounds, material incompatibility, cross-contamination, workplace ventilation, concerns related to aging, thermal cycling, and chemical attack, and documentation of expiration dates and lot numbers.
"From the outset in developing the Medalist MD-500 Series of medical tubing compounds, Teknor Apex has had the goal of establishing these innovative TPEs as truly practical alternatives to PVC," said Ross Van Royen, senior medical market manager for the company's Thermoplastic Elastomer Division. "To that end we have worked with Eldon James and other companies that have real-world expertise in the design, production, assembly, or clinical use of medical tubing."
Compared with PVC, the tubing compounds in the Medalist MD-500 Series exhibit comparable crystal clarity and mechanical properties; provide similar clamp resilience and resistance to kinking and necking; have a similar "feel"; and are substantially more flexible and significantly less dense than PVC. At the same time they undergo minimal color shift upon heat aging after exposure to gamma irradiation, the most severe type of sterilization. A typical compound in the series, Medalist MD-575, actually exhibits 70% less heat-aged color shift than a gamma-stabilized PVC compound of comparable hardness.
Information about Eldon James Corporation is available at www.eldonjames.com.
MEDALIST® THERMOPLASTIC MEDICAL ELASTOMERS make up a broad array of high-purity styrenic, olefinic, vulcanizate, and alloy compounds. Hardness offerings range from ultra soft gels at 25 Shore OO to hard yet ductile compounds at 85 Shore D. Teknor Apex can further broaden customer options by customizing the surface aesthetics, haptics, clarity, and color. An expandable registered binder on Medalist products provides a comprehensive body of test data and resources for designers and processors and is available to qualified professionals in the medical device and healthcare product industries. It can be requested from the Medalist website at www.medalistmd.com or by emailing Teknor Apex at email@example.com.
The Thermoplastic Elastomer Division of TEKNOR APEX COMPANY is the most diversified manufacturer of TPEs, offering broad product families based on six generically distinct chemistries. Headquartered in Pawtucket, Rhode Island, U.S.A., the division compounds TPEs at eight locations in the U.S., Europe, and Asia and is an international supplier to the appliance, automotive, construction, medical-device, wire and cable, and other consumer and industrial product industries. Other plastics businesses of Teknor Apex include the Bioplastics, Nylon, Specialty Compounding, and Vinyl Divisions and Teknor Color Company. Visit www.teknorapex.com.