The action mechanism of starch ether in drymortar
Gypsum plaster is widely used in dry-mixed mortar products. Whether it is hand-applied plaster or machine-applied plaster, starch ether plays a very important role. The mechanism of starch ether significantly affects the thickening of freshly mixed mortar, providing a thickening effect for plaster. Thus, plaster can quickly reach a suitable consistency during construction due to the unique mechanism of starch ether. Starch ether is a very effective thickener for gypsum plaster. Very low starch ether content, usually in the range of 0.03%-0.1%, can already achieve a good thickening effect. This allows the plaster to be used immediately, and a retarder is used to extend the overall working time.
In the traditional pure plaster, when the plaster and water are mixed, the viscosity increases rapidly. This makes the plaster have the expected consistency, suitable for the application in a very short period of minutes. The mechanism of starch ether, however, ensures efficiency even with a retarder. The addition of retarder prolongs the working time of the plaster. However, it is necessary to wait until the consistency reaches the required interval to be suitable for the application. The operating time is still relatively short.
The addition of retarder prolongs the working time of the plaster. However, it is necessary to wait until the consistency reaches the required interval to be suitable for the application. The operating time remains relatively short. When starch ether and retarder are added to the product at the same time, the required consistency can be reached immediately due to the efficient mechanism of starch ether. The resulting plaster can be used immediately. The operable time can be set by the amount of retarder to extend the operable time. The content and type of starch ether determine the degree of thickening of plaster. Through special chemical treatment of starch ether, lower dosage can be used to obtain higher thickening effect. This applies in both alkaline and neutral systems. The mechanism of starch ether is key to its effectiveness in achieving desired properties.
Performance of Starch Ethers in Drymix Mortars
