Performance Characteristics of Polycarboxylate Superplasticizers
Release Time:
2020-06-19
Source:
Performance Characteristics of Polycarboxylate Superplasticizers
Polycarboxylate-based water-reducing agents are currently among the most technologically advanced, promising in application, and superior in overall performance concrete plasticizers (water reducers). They are formulated as composite products consisting of carboxylic acid–grafted multicomponent copolymers combined with other effective admixtures. Comparative performance tests against similar products both domestically and internationally demonstrate that polycarboxylate-based water-reducing agents achieve advanced levels in technical performance indicators and cost-effectiveness.
Performance characteristics of polycarboxylate-based water-reducing agents:
1. Low dosage and high water-reducing efficiency, with a water-reduction rate of up to 45%;
2. When the slump is low, the loss is minimal; for ready-mixed concrete, the slump loss rate is less than 5% after 1 hour and less than 10% after 2 hours.
3. The strengthening effect is significant: 3-day compressive strength of concrete increases by 50–110%, 28-day compressive strength increases by 40–80%, and 90-day compressive strength increases by 30–60%.
4. The concrete exhibits excellent workability, with no segregation or bleeding, and a uniform appearance. When used to produce high-grade concrete, it demonstrates good cohesiveness and is easy to mix.
5. Moderate air content has no adverse effect on the elastic modulus of concrete and exhibits good freeze-thaw durability;
6. It can reduce the early hydration heat of cement, which is beneficial for mass concrete and summer construction;
7. Excellent adaptability: good compatibility with cement and mineral admixtures, excellent temperature tolerance, and outstanding compatibility with various types of cement and mineral admixtures, thereby resolving the issue of poor compatibility between other types of water-reducing agents and cementitious materials.
8. Low shrinkage: significantly reduces concrete shrinkage and exhibits markedly superior freeze–thaw resistance and carbonation resistance compared with ordinary concrete; substantially enhances concrete’s volumetric stability and long-term durability.
9. Extremely low alkali content, ≤0.2%, effectively preventing alkali-aggregate reaction.
10. The product exhibits excellent stability, with no layering or sedimentation during long-term storage and no crystal precipitation at low temperatures.
11. The product is green and environmentally friendly, formaldehyde-free, and classified as an eco-friendly product;
12. Excellent economic benefits: the overall project cost is lower than that of other types of products, and under the same strength requirements, cement consumption can be reduced by 15–25%.
