Rubber closures are very important packaging materials that are usually used in penicillin bottle, syringe, vacutainer blood collection tube and other medical packaging and medical apparatus. The most common materials used for rubber closures include natural rubber and butyl rubber, etc.

Since there are different molecular structure, composition and manufacturing process of rubber closures, the safety and corrosion resistance may be distinct from each other. Besides, the seal performance and puncture resistance and other mechanical properties are also what we shall pay more attention to. To be specific, if the puncture resistance of the rubber closure is too high, it may need a large piercing force to puncture through and cause inconvenience to the doctors and nurses when they try to draw medicine or blood from the bottles or vials with rubber closures. However, if the puncture resistance of rubber closure is too low, fragments may be produced in puncturing process and those fragments may enter the medicine and cause danger to human health. Therefore, the medical rubber closures should have proper puncture resistance.

This article provides a simplified test method of puncture resistance of medical rubber closures for your reference. The test specimens are closures for penicillin bottle and the testing instrument is Labthink’s MED-01 Medical Packaging Tester.

Figure 1. Medical Rubber Closures

Figure 2. MED-01 Medical Packaging Tester

The tests can be performed according to the following procedures.

(1)   Prepare 10 pieces of penicillin bottles with rubber closures. Add half of the bottles with water. Then close the rubber closures.

(2)   Put those penicillin bottles into high pressure evaporating pan and process them at 121 ℃ for 30 minutes.

(3)   Remove the bottles from the evaporating pan and cool down to room temperature.

(4)   Set specimen name, test times (10), test speed (200mm/min) and other test parameters.

(5)   Install the puncturing needle in the upper sample grips. Fix one specimen with fixtures.

(6)   Click Test to start the test. The puncturing needle will move downward and puncture through the rubber closure. The force values will be displayed in the real time and the maximum force value is reported as the puncture force.

(7)   Repeat step 5 to 6 until all the specimen tests are finished.

For more details about MED-01 Medical Packaging Tester, please visit www.labthink.com

About Labthink Instruments Co., Ltd:

Labthink Instruments Co., Ltd is one leading supplier of packaging testing instruments, which is headquartered in Jinan, China and operated in Boston, U.S.A.