Freeze-Thaw Stability of Latex Compounds

Manufacturer: We are manufacturing synthetic latex based coating compounds for EU markets. Recently we have had complaints about the Freeze-Thaw stability of our products. Can you please suggest a good but easy method to measure this? Would appreciate if you could advise us on how to improve freeze-thaw stability.

John Woon (Senior Latex Consultant): You can use the following method:

1) Fill up a glass bottle (of capacity of about 250 gram) with the latex compound to three-quarter full.
2) Subject the bottle to 10 cycles of 18 hours freezing at - 20°C followed by 6 hours thawing at room temperature.
3) Examine the sample for signs of gelling and precipitation (coagulation).

If the test confirms that the compound has poor resistance to freeze/thaw, proceed to do the following:

1) Add ethylene glycol at 1 to 2% into a fresh sample of the latex compound and stir gently for 1 hour.
2) Repeat the freeze-thaw test.

If ethylene glycol cannot work, please let me know and I would suggest other alternatives.