Appearance Color Of Polycarboxylate Superplasticizer

Appearance color of polycarboxylate superplasticizer

After undergoing esterification reaction to synthesize polycarboxylate water reducer, the entire process of the admixture industry has been converted to one-step synthesis of ethers. The color of the mother liquor obtained by one-step synthesis of ethers is clear and transparent or slightly whitish. The whitening is related to the monomer manufacturer and does not affect the quality.

The different colors of water reducers or admixtures are mainly divided into two categories. The first is the difference in the color of the mother liquor itself, and the second is the colorless mother liquor that appears red or other colors after compounding.

In addition to the colorless and transparent mother liquor, the mother liquor of esters or the mother liquor using ferrous sulfate as reducing agent will appear dark red. At present, these two types of products are rare. The last time I came into contact with ester water reducer mother liquor was back in 2013, and then I used ether mother liquor. There are not many processes that use a large amount of ferrous sulfate as a reducing agent, and I just synthesized it in the laboratory for research. There are quite a few processes using ferrous sulfate in a small amount on the market, as long as the amount is not excessive, the color of the mother liquor will not be greatly affected. Excessive ferrous ions are oxidized to trivalent iron and become a red dye. Ferric iron can act as a dyeing agent in other industries.

When the mother liquor is left for a long time, the mother liquor of some manufacturers will gradually change from colorless and transparent to light red. This is mainly because the ratio of the redox agent added during the synthesis is slightly out of balance. The common reason is that the amount of vc is too large. This has no effect on performance.

Excessive vitamin C is the main cause of discoloration of mother liquor. The mother liquor just synthesized by many manufacturers is colorless and transparent, but the product turns red after being stored for no more than two days and then observed through a large plastic tank. This is mainly caused by the oxidation of the reducing agent remaining in the mother liquor by air. For the same batch of goods, the rate of discoloration of the product in isolation from air will be reduced after being sealed in a sample bottle. This phenomenon will not affect the quality problem.

The discoloration of the mother liquor occurs during the storage process of the company and the degree is not deep. Generally, the mother liquor sent to customers either does not change color or has been stored for a few days and has completed the discoloration process. This phenomenon will not cause customers to question.