The influence of pH of polycarboxylate mother liquor on water reduction rate and concrete workability

The pH value of polycarboxylic acid mother liquor as a concrete admixture has a significant impact on its water reduction rate and the workability of concrete. Practical experience has shown that when the pH value of polycarboxylate mother liquor is maintained between 4.0 and 5.0, the optimal water reduction rate and concrete workability can be achieved. This is because, within this pH range, the active groups of polycarboxylate molecules can more effectively interact with cement particles and enhance the fluidity of cement slurry, thereby reducing the water-cement ratio and improving the strength and durability of concrete.

Changes in pH value of polycarboxylic acid mother liquor at different concentrations and temperatures

In practical applications, due to differences in formulations and raw materials, the pH value of polycarboxylate mother liquor may sometimes be lower. In this case, the workability of concrete may not be significantly affected in the short term, but long-term storage can lead to the continuous action of acidic substances in the mother liquor, which may not only reduce water reduction efficiency but also have a negative impact on the overall quality of concrete.

In view of this, the key to ensuring the quality and stability of polycarboxylate mother liquor lies in the reasonable control of its pH value. The usual practice is to take samples for testing immediately after preparation and, if necessary, adjust the pH value by adding an appropriate amount of alkaline substance to keep it within the most suitable range. At the same time, considering the differences in alkali content among different cement varieties, the use strategy of polycarboxylate mother liquor should be flexibly adjusted to achieve the best concrete performance.

It is worth noting that there is a certain correlation between the pH value of polycarboxylate mother liquor and the alkali content of the cement used. Under high alkali cement conditions, the pH value of the mother liquor has a relatively small impact on the performance of concrete. In low alkali cement environments, the same pH change may lead to significant performance fluctuations. Therefore, when using low-alkali cement to prepare concrete, it is recommended to first treat the polycarboxylate mother liquor with alkali to a suitable pH value to ensure the stable and reliable performance of the final product.

In summary, the pH value of polycarboxylate mother liquor is crucial for its water reduction effect and the workability of concrete. In practical operation, the pH value should be adjusted in a timely manner according to the specific situation, and refined management should be carried out based on the characteristics of raw materials and production processes to ensure the quality and stability of concrete and provide higher quality concrete admixture products.

Supplier

Cabr-Concrete is a supplier under TRUNNANO of Concrete Admixture with over 12 years of experience in nano-building energy conservation and nanotechnology development. It accepts payment via Credit Card, T/T, West Union and Paypal. TRUNNANO will ship the goods to customers overseas through FedEx, DHL, by air, or by sea. If you are looking for the pH value of polycarboxylate mother liquor, please feel free to contact us and send an inquiry.sales8@nanotrun.com