Stearic acid-treated calcium carbonate compositions having low or no detectable free stearic acid and related methods
View Patent ↗A method for treating calcium carbonate includes combining calcium carbonate with an amount of stearic acid and an amount of water to form a mixture, the amount of water being at least about 0.1% by weight relative to the total weight. The method further includes blending the mixture to form a stearic acid-treated calcium carbonate composition.
1. A method for treating calcium carbonate, the method comprising:
combining calcium carbonate with an amount of stearic acid and an amount of water to form a mixture, the amount of water ranging from greater than 1.0% to about 20% by weight relative to the total weight, and wherein the amount of stearic acid is at least about a monolayer concentration; and
blending the mixture to form a stearic acid-treated calcium carbonate composition.
2. The method of claim 1 , wherein the mixture is blended at a temperature of at least about 65° C.
3. The method of claim 1 , wherein the mixture is blended at a temperature ranging from at least about 65° C. to about 200° C.
4. The method of claim 1 , wherein the mixture is blended for a time period ranging from at least about 1 second to about 10 minutes.
5. The method of claim 1 , wherein the mixture is blended for a time period ranging from at least about 2 seconds to about 1 minute.
6. The method of claim 1 , wherein the mixture is blended for a time period sufficient for a majority of the stearic acid to react with the calcium carbonate.
7. The method of claim 1 , wherein the amount of stearic acid is greater than monolayer concentration.
8. The method of claim 1 , wherein the amount of water ranges from at least about 5% to about 15% by weight.
9. The method of claim 1 , wherein the amount of free stearic acid associated with the stearic acid-treated calcium carbonate composition is less than about 20% relative to a monolayer concentration.
10. The method of claim 9 , wherein no free stearic acid is associated with the stearic acid-treated calcium carbonate composition.
11. The method of claim 1 , further comprising combining the stearic acid-treated calcium carbonate composition with a polymer.
12. The method of claim 1 , wherein the calcium carbonate has a (d 50 ) ranging from about 0.01 μm to about 10 μm.
13. The method of claim 1 , wherein the calcium carbonate has a (d 50 ) less than or equal to about 3 μm.
14. A method for treating calcium carbonate, the method comprising:
combining calcium carbonate with an amount of stearic acid and an amount of water to form a mixture, the amount of water ranging from greater than 1.0% to about 20% by weight relative to the total weight, and wherein the amount of stearic acid is at least about a monolayer concentration; and
blending the mixture to form a stearic acid-treated calcium carbonate composition,
wherein the mixture is blended at a temperature sufficient for at least a portion of the stearic acid to react with the calcium carbonate.