Leaching of Latex Medical Tubing

Manufacturer: We are making medical tubings with NR latex compounds but the customer requires a very stringent control of toxicity level of our products. To achieve this, we are attempting to further improve our leaching process and would appreciate very much if you could give us some guidance. 

 

John Woon (Senior Latex Consultant): Leaching is a big subject which entails at least 7 steps of mechanism. I can prepare a detailed report for you if required. In the mean time, here is my brief suggestion:

1) Higher leach water temperature is to be used to ensure maximum solubility of all the hydrophilic materials. But cold water leaching is to be included if non-ionic surfactants are also used.

2) Frequent replenishment with clean water is advisable.

3) Turbulence in the leaching tank would help.

4) Leach for as long a period as practically possible.

5) Adopt both wet and dry leaching.

6) Check copper (ion) level in the leach water.

If you are using a post-vulcanisable latex compound, I suggest you evaluate prevulcanised latex which has a comparatively low level of toxicity.