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ASTM D153-84(R2020) pdf free download

ASTM D153-84(R2020) pdf free download.Standard Test Methods for Specific Gravity of Pigments
4. Apparatus and Materials
4.1 Pycnometer—A pycnometer (Note 1) having a 50-mL capacity. N OTE 1—The Weld type with the cap seal on the outside of the neck of the bottle is preferred because there is less danger of trapping air just under the capillary tube than with types having the ground glass seal on the inside of the neck. 4.2 Water Bath, maintained at 25 6 0.5°C and equipped with a stirring device. 4.3 Manometer, open- or closed-tube (see Part f of the apparatus for Test Method C), made of glass tubing 6 mm in diameter, fitted with rubber pressure tubing attached to a T-joint leading to the desiccator and the pump. For the open-tube type 860 mm of mercury shall be used. The difference in levels of the mercury in the manometer when the system is in operation, subtracted from the barometer reading taken at the same time, shall be considered the absolute pressure of the system in millimetres of mercury. 4.4 Desiccator, glass, constructed with heavy walls to with- stand a vacuum of one atmosphere, and with an opening at the side. 4.5 Vacuum Pumps—A laboratory water vacuum-type pump (Note 2), to remove the greater portion of air in the desiccator, and an oil vacuum-type pump, motor-driven, and capable of reducing the absolute pressure of the system to 3 mm. N OTE 2—The water vacuum pump may be omitted if the rate of evacuation with the oil pump can be controlled so as to avoid a rapid ebullition of entrapped air and possible loss of specimen. 4.6 Thermometer, having a range from 0 to 60°C, and graduated in 0.1°C divisions. 4.7 Weighing Bottle, wide-mouth cylindrical glass (about 30 mm in height and 70 mm in diameter), provided with a ground-glass stopper.4.8 Immersion Liquid—Kerosine has been found to be a good wetting vehicle for most pigments, and shall be used generally as the immersion liquid. Refined, white kerosine of narrow evaporation and boiling range shall be used. With some pigments that are not wetted well with kerosine, other immer- sion liquids such as glycerin, ethylene glycol, tetrahydronaphthalene, etc., may be substituted. The liquid must have a low evaporation rate and narrow boiling range, and the same procedure shall be followed as with kerosine. Water is not a preferred liquid because of the possibility of frothing.
7. Procedure
7.1 Drying—Dry the pigment, preferably in an electric oven, at 105 6 2°C for 2 h. 7.2 Weighing—Transfer to a clean, dry, weighed pycnometer, sufficient sample to form a layer approximately 20 mm ( 3 ⁄ 4 in.) deep. For black, blue, and lake pigments of low specific gravity, use about 1 g of sample; for inert crystalline pigments, about 4 g; for opaque white pigments, 7 to 10 g; and for red lead, from 15 to 20 g. Weigh pigments ofa hydroscopic nature from the weighing bottle. 7.3 Number of Specimens—Run all samples at least in duplicate. 7.4 Addition of Kerosine—Add enough kerosine to the pycnometer to form a clear layer approximately 1 ⁄ 4 in. (6 mm) above the pigment. When necessary, stir the specimen with a polished round-bottom glass rod until completely covered by kerosine, adding more kerosine ifnecessary. Wash the rod with kerosine, adding the washings to the pycnometer. 7.5 Removal ofOccluded Air—Place the pycnometer in the desiccator. Close the desiccator and attach to the water pump until the greater part of the air is removed from the system. Complete this procedure within a period of 5 to 10 min. Close the system with a pinchcock and attach the desiccator to the oil pump for the removal of the small amounts of air given off at the low pressures obtainable with the oil pump. Use the manometer to indicate whether the oil pump is giving the proper vacuum. When the manometer indicates that the abso- lute pressure is 3 mm and constant, cut off the oil pump for short periods, taking care that the vacuum does not change materially due to leakage.

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