Currentbuzz
Schematic drawing of the chemical structure of the synthesized PCE superplasticizer a 623x500 - Pce superplasticizer

Pce superplasticizer

superplasticizer admixture powder 500x500 1 - Pce superplasticizer

As a new generation of high-performance water reducers in concrete, polycarboxylate superplasticizer (PCE) has attracted significant interest in academia and industry, compared to naphthalene sulfonate-formaldehyde (NFS) superplasticizer. NFS is a linear polymer, while PCE is a comb polymer, which is generally prepared by grafting a long side chain with a polyoxyethylene (PEO) group. The side chain of PCE provides an effective barrier to the aggregation of cement particles suspended in water. Therefore, excellent dispersion performance of PCE was observed. Considering environmental friendliness, high water reduction rate, prolonged droplet retention rate, and easy structural modification, PCE has gradually become an alternative to the NFS.

The polycarboxylate and superplasticizer also showed some limitations. One of the main concerns is its low tolerance for clay minerals in concrete. PCE cannot effectively prevent clay minerals in concrete from forming aggregates. This is not trivial as it will lead to a drastic decrease in the dispersion of clay minerals in the concrete and its stability. For a practical application, it is desirable that the clay is dispersed in the concrete evenly without forming aggregates over a certain period of time. The main clay minerals in concrete are montmorillonite (MMT), illite, and kaolin. 

Mmt has a layered structure composed of silica tetrahedron and alumina octahedron in a ratio of  PCE adsorption in Mmt is approximately 100 times greater than that of Portland cement. The strong affinity of PCE along the side chain with Mmt allows effective insertion of PCE into the interlayer of MMT, thus inhibiting PCE performance in fresh concrete. Some researchers have reported that intercalation adsorption is the dominant mechanism for MMT-PCE adsorption. When the concrete aggregate contains clay minerals, the aggregates often cause the rapid loss of flow of the concrete, hence the greater amount of PCE used to meet concrete requirements. This phenomenon is often referred to as poor tolerance to PCE clay In such a circumstance, the tolerance of PCE to clay minerals in the cement must be improved to increase the flowability of the cement.

So, the polycarboxylate and the superplasticizer are very significant in the field of construction though, they also showed some limitations. One of the main concerns is its low tolerance for clay minerals in concrete. PCE cannot effectively prevent clay minerals in concrete from forming aggregates. This is not trivial as it will lead to a drastic decrease in the dispersion of clay minerals in the concrete and its stability. For practical application, it is desirable that the clay is dispersed in the concrete evenly without forming aggregates over a period of time.

Check out this article!

Teha Azman

logo 300x54 - Pce superplasticizer
December 2020
M T W T F S S
 123456
78910111213
14151617181920
21222324252627
28293031  
logo 300x54 - Pce superplasticizer
December 2020
M T W T F S S
 123456
78910111213
14151617181920
21222324252627
28293031