配方类型: |
EMULSIONS |
配方说明: |
Soft Asphalt Emulsion |
配方组成: |
"Carbopol" 941/1.50 Soft Asphalt/400 Sodium Hydroxide (10% solution)/4.50 Water/4000.0 "Ethomeen" C-25/0.75 |
配制方法: |
Carefully disperse the "Carbopol" 941 in the water. After thorough dispersion, neutralize with the sodium hydroxide followed by the "Ethomeen" C-25. Heat this mucilage to 65-70'C. (The water can be heated before "Carbopol" 941 and neutralizer are added as this will assist dispersion of the "Carbopol" 941.) Separately heat the asphalt to 85'C. Utilizing moderately high-shear mixing, slowly add the molten asphalt to the water mucilage. Add the asphalt no faster than the rate of dispersion. If the asphalt is added too rapidly, the emulsion will invert and separate. When the asphalt has been added, continue mixing for a short time to ensure uniformity. Shock-cool the emulsion without mixing and allow it to remain undisturbed until its temperature falls to 30-35'C. An emulsion prepared in the foregoing manner has a final pH of 6.5 and a viscosity of 5500 cps (Brookfield, 20 rpm). It is stable on aging and very smooth in appearance. |
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