| 6176314 |
Low density well cement compositions and method of use |
— |
2001-01-23 |
| 5380705 |
Drilling mud comprising tetrapolymer consisting of n-vinyl-2-pyrrolidone, acrylamidopropanesulfonicacid, acrylamide, and acrylic acid |
Billy L. Swanson, Bharat B. Patel |
1995-01-10 |
| 5294651 |
Fluid loss additives for well cementing compositions |
— |
1994-03-15 |
| 5153240 |
Fluid loss additives for well cementing compositions containing a tetrapolymer |
— |
1992-10-06 |
| 5135909 |
Drilling mud comprising tetrapolymer consisting of N-vinyl-2-pyrrolidone, acrylamidopropanesulfonic acid, acrylamide, and acrylic acid |
Billy L. Swanson |
1992-08-04 |
| 5109042 |
Fluid loss additive for cement slurries containing a n-vinyl-2-pyrrolidone-.omega.-2-acrylamido-2-methylpropane sulfonate-.omega.-acrylic acid-.omega.-acrylamide polymer |
— |
1992-04-28 |
| 5041630 |
Well cement slurries and dispersants therefor |
Bharat B. Patel |
1991-08-20 |
| 4923516 |
Well cement slurries and dispersants therefor |
Bharat B. Patel |
1990-05-08 |