The Synthesis of Carboxyl Calcium Lignosulfonate and Its Applications as Water Reducer

p‐Aminobenzoic acid and calcium lignosulfonate (CL) are used as main raw materials in the synthesis of carboxyl calcium lignosulfonate (CCL). The surface activity of CCL is measured, and the properties of cement particles with CCL are investigated such as adsorption quantity and Zeta potential. Test results show that CCL has higher surface tension, lower adsorption quantity on cement than CL, the Zeta potential of cement particles with CCL is similar to that of cement particles with CL, the dispersing ability of CCL is stronger than that of CL, the viscosity loss of cement paste with CCL is less than that with CL, and the compressive and flexural strength of mortars with CCL are higher than that with CL.

Keywords:

• Carboxyl group
• steric hindrance effect
• dispersing ability
• surface activity
• viscosity

Project supported by the National Natural Science Foundation of China (Grant 50373017), Young and Middle‐aged Scientist Foundation of Shandong Province (Grant 02BS051) and Shandong Provincial Education Department (Grant J02C06).