| 配方類型： |
METALS |
| 配方說明： |
Release for Graphite Molds |
| 配方組成： |
"Ethomeen" C-25/0.25
"Carbopol" 941/0.25
Mineral Oil/50.00
Sodium Hydroxide (10% solution)/1.40
Graphite/25.00
Water/50.00 |
| 配制方法： |
Carefully disperse the "Carbopol" 941 in the water. After complete dispersion, add the sodium hydroxide and then the "Ethomeen" C-25. Next, disperse the graphite in the mineral oil. It is advisable to deaerate this mixture before the next step because of the large amount of air adsorbed on the graphite particles. Lastly, thoroughly mix inn the oil-graphite blend and stir to uniformity. The viscosity of the finished suspension-emulsion is 33,000 cps (Brookfield, 20 rpm) and the pH is 10.2.
As the nature of the graphite has a major effect on the efficiency of the "Carbopol" resins, it is important to carefully consider each graphite separately. For instance, when "No.4XX Special Graphite" is substituted for the "5XX," flocculation occurs. An excellent, stable suspension-emulsion is prepared using the "No.4XX Special Graphite" by slightly altering the formulation: the sodium hydroxide and "Ethomeen" C-25 content is reduced to 0.70 and 0.25 respectively, resulting in a pH of 6.4. Because of its wide operatin |
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