The fluidity of waterproof mortar plus polycarboxylate superplasticizer is too strong.

[Chanliss]

Polymer waterproof mortar with polycarboxylate superplasticizer has extreme fluidity and severe construction sagging. Is there any way to improve it? Or is there any water-reducing agent recommendation that does not change the state of the mortar?

 

[Luis]

For brushing things, use the water-reducing agent as little as possible. The water-reducing agents in such materials do not reduce water or flow; the most significant purpose is to prevent powder from beating, improve dispersibility, and the workability of mortar. So the principle is to add less and meet the requirements.

If you want to roll the construction, add some bentonite or a little kaolin. The principle of this thing is similar to paint.

 

[Alex]

Avoid using polycarboxylate superplasticizer for plastering, which will cause air entrainment and sags since the fluidity is too good.

It is more appropriate to use a small amount of melamine for waterproofing. The dosage doesn’t need to be high.

For constructability, you can start with things like cellulose ether. However, using water-reducing agents to improve constructability is not reliable.

 

[Cassie]

You can consider using a water-reducing agent with a low rate, such as a melamine water-reducing agent or naphthalene water-reducing agent. However, there are too many functional polycarboxylic acid groups, so choosing is troublesome.

 

[William]

The water-reducing rate of polycarboxylate is too high, but only if the technical level can keep up with it, and the amount of addition should be small.
Lignin, naphthalene, and melamine have low water-reducing rates; you can choose the appropriate one after experimentation.

 

[Chanliss]

You can consider using a water-reducing agent with a low rate, such as a melamine water-reducing agent or naphthalene water-reducing agent. However, there are too many functional polycarboxylic acid groups, so choosing is troublesome.

The effect of naphthalene could be better and specifically influence the strength and strong moisture absorption. Compared with melamine, it feels average. The impact of polycarboxylate is better, but the plastering construction needs to be simplified. Will choosing a different type of polycarboxylate be improved? If the amount of melamine is generally controlled, will it affect the strength?

 

[Cassie]

The effect of naphthalene could be better and specifically influence the strength and strong moisture absorption. Compared with melamine, it feels average. The impact of polycarboxylate is better, but the plastering construction needs to be simplified. Will choosing a different type of polycarboxylate be improved? If the amount of melamine is generally controlled, will it affect the strength?

Now that you have compared them, if you want to improve the construction, you can consider other aspects, like water retention and thixotropy.