Electrical Conductivity to Asses Quality of Natural Rubber Latex

Manufacturer: We are manufacturers of latex dipped products using natural rubber latex. We have been advised to look into a faster and practical method to assess the quality of the latex beside those specified by ISO and ASTM. What do you think of electrical conductivity of latex?
 
John Woon (Senior Latex Consultant): As natural rubber latex ages, it's quality deteriorates as measured by KOH Number and VFA Number tests, both values of which would increase. We also know that the electrical conductivity of the latex would likewise increase as the latex ages.

Electrical conductivity test is not as sensitive and accurate as VFA test to access the quality of the latex. However, if you want to have a quick indication on how the latex performs (based on the past records of conductivity), you can do this simple test but it must be followed with a VFA test.

Unlike VFA test, both KOH and electrical conductivity tests do not differentiate between the high molecular weight stabilising ions and low molecular weight destabilising ions (i.e. the good and bad ions).