At the Medical Design & Manufacturing event in Anaheim, CA, in February 2015, Teknor Apex (Pawtucket, RI) introduced a rigid PVC that can replace polycarbonate (PC) in clear medical components. PC is prone to cracking, or crazing, which is caused by the migration of plasticizer when it comes in contact with flexible PVC parts. The rigid PVC developed by Teknor Apex reportedly eliminates the stress cracking that may occur at the interface of PC with flexible PVC components, while achieving strength and clarity properties similar to PC.
Teknor Apex has compiled test data showing that it took the new Apex SCR rigid PVC grades one to two and one-half weeks or longer to exhibit stress cracking after prolonged contact with flexible PVC. Test samples consisting of conventional rigid PVC or a PC widely used in medical devices cracked within a matter of hours, according to the company.
