Let see how may types of solids are there in liquid products or materials:
Total solids - includes all solids present in a water sample. Determined directly by evaporating a known volume of an unfiltered water sample in a 105 Deg C oven. Total dissolved solids - includes all solids present in a water sample filtered through a 1.2 m m filter. Determined by evaporating a known volume of the filtrate sample in a 105 Deg C oven. Total suspended solids - includes all solids present in a sample that remain on a 1.2 m m filter. Determined by filtering a known volume of sample and placing the filter and filter container in a 105 Deg C oven for 24 hours to evaporate the water. Fixed solids - solids that remain after firing a sample in a 550 Deg C muffle furnace. Can be performed on total, dissolved, or suspended samples to determine - total fixed solids, fixed dissolved solids, or fixed suspended solids.
Volatile solids - solids that removed by firing a sample in a 550 Deg C muffle furnace. Can be performed on total, dissolved, or suspended samples to determine - total volatile solids, volatile dissolved solids, or volatile suspended solids.
6. Suspend the coated disc in water and weigh again. Let it be W4
grams. Volume of the coated disc V1 = (W3-W4) / d, the density of water. Volume
of the dried coating = Vd = V1- V. Volume of wet coting = VW = (W3-W1)/(WxP).
7. Volume of solids = ((V1-V)/VW) x 100 OR (Vd / VW) X 100.
As per ASTM D 2697, test method is intended to provide a measure of the
volume of dry coating obtainable from a given volume of liquid coating. This
value is useful for comparing the coverage (square feet of surface covered at a
specified dry film thickness per unit volume) obtainable with different coating
products.
As per IS 101 ( Part 8/&e 6 ) : 1993 – Volume Solids can be measured as follows:
1. Take Stainless Steel Disc 60
mm diameter and 0.70 mm thickness with a small hole 2 to 3 mm from the edge,
with the hole and string to hang in the testing cabinet.
2. Note the weight of the
stainless-steel disc. Dry the disc in an oven at 105°C for 10 minutes and cool.
Weigh the disc in air. Let it be W1, grams. Suspend the disc in water and weigh
again. Let it be W2 grams. Volume of the
disc V = (w1-W2) / d, the density of water.
3. Determine the weight of
non-volatile content of the liquid coating material by drying a known amount of
paint at 105°C for 3 hours. Let it be W grams.
4. Determine the specific gravity
of the paint using mass per litre cup. Let it be P.
5. Dip the disc in the paint sample for 10 minutes and take out the
disc. Allow the excess coating material to drain off. Blot the coating material
off the bottom edge of the disc so that beads or drops do not dry on the bottom
edge of the disc. Dry the disc at 105°C for 3 hours and cool. Weigh the coated
disc in air. Let it be W3, grams.
As per ASTM D 2697, test method is intended to provide a measure of the
volume of dry coating obtainable from a given volume of liquid coating. This
value is useful for comparing the coverage (square feet of surface covered at a
specified dry film thickness per unit volume) obtainable with different coating
products.
For various reasons the value obtained may not be equal to that predicted from simple additivity of the weights and volumes of the raw materials in a formulation. One reason is that the volume occupied by a solution of resin in solvent may be the same, greater, or less than the total volume of the separate ingredients: such contraction or expansion in resin solutions is governed by a number of factors, one of which is the extent and direction of spread between solubility parameters of the resin and solvent. The spatial configuration of the pigment particles and the degree to which the spaces between the pigment particles are filled with the binder also affect the volume of a dry coating formulation. Above the critical pigment volume concentration, the apparent volume of the dry film is significantly greater than theoretical due to the increase in unfilled voids between pigment particles. The use of volume nonvolatile matter values in such instances should be carefully considered as the increased volume is largely due to air trapped in these voids.
Apply a coating of the mixed material as per manufacturer’s
specification.
There is one term we all come across called TSS, Total Suspended Solids. This can be tested using IS 3025 - part 17. Let see how to test the TSS:
Many thanks to google.com
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