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I need an accurate weight-per-gallon of your paint sample but can't get it because your paint has entrapped air. What do you suggest?
The following test method can be used to determine the actual weight per gallon of a paint with apparent trapped air

Reduce a given weight of paint with an equal weight of water and add a tiny drop or two of a silicone defoamer. Stir gently and allow to stand for 5 minutes.

Then stir gently again until well mixed and measure the weight-per-gallon of the mixture using a weight-per-gallon cup and scale, just as you would for any paint sample.

Calculate the deaerated weight of the paint using the following formula:



Where		 image Z = (X)(Y) / (2X - Y)

X = weight of the reducing solvent (in this case water)
Y = weight of the paint/water blend
Z = deaerated weight of the paint

Tips:

- The volume of the paint/water mixture should be just enough to fill the weight-per-gallon cup and the mixture should be well stirred just as you pour it into the cup. This insures that the paint doesn't settle and get left in the bottom of the mixing container

- A blend of 50 grams paint / 50 grams water works well for paints with weights up to around 10# / gallon. If the actual, expected weight of the paint is heavier than 10#, increase the weight of paint/water used to make the blend so that you will have enough volume to fill the weight-per-gallon cup.

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How can I improve shear stability of asphalt emulsions modified with styrene butadiene (SB) latex?
Polyacid type dispersants will improve the shear stability of SB latexes used to modify asphalt emulsions. Higher molecular weight dispersants work best in this application. Examples of some suitable dispersants are Tamol 850 and Colloid 202.

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