some problems in the application of polycarboxylate superplasticizerii
Compatibility of polycarboxylate superplasticizer with other admixtures.
Beijing Dongke United Technologies Co.,Ltd.
If you are interested in concrete additives, you must not miss this news. We are a professional manufacture of concrete additives, the most important product in concrete additives is water reducer. But what is concrete plasticiser? Let me show you:
As a kind of concrete additive, concrete plasticiser is also very important. What is concrete plasticiser? Plasticizers are a substance that is added to a material to make it softer and more flexible, to increase its plasticity, to reduce its viscosity or to reduce friction during its manufacturing process.
Usually 1-2% plasticizer per unit weight of cement is sufficient. Adding excess plasticizer will cause excessive segregation of the concrete and is not recommended. Depending on the specific chemicals used, using too much plasticizer may cause retardation.
Plasticizers are typically produced from lignosulfonates, which are by-products of the paper industry. Superplasticizers are usually produced from sulfonated naphthalene condensates or sulfonated melamine formaldehyde, although newer products based on polycarboxylate ethers are now available.
Traditional lignosulfonate-based plasticizers, naphthalene and melamine sulfonate-based superplasticizers disperse the flocculated cement particles through an electrostatic repulsion mechanism. In ordinary plasticizers, the active substance is adsorbed and stuck to the cement particles, making them negatively charged, causing repulsion between the particles.
Lignin, naphthalene and melamine sulfonate superplasticizers are organic polymers. The long molecules wrap them around the cement particles, giving them a highly negative charge that repels each other.
Polycarboxylate ether superplasticizers (PCE) or just polycarboxylates (PC) act differently from sulfonate-based superplasticizers to disperse the cement through steric stabilization. This dispersed form is more effective and improves the workability of the cementitious mixture.
Compatibility of polycarboxylate superplasticizer with other admixtures.
Polycarboxylic acid high-efficiency water reducing agent is characterized by low dosage and high water reducing rate.
Polycarboxylic acid water reducing agent with high efficient water reducing performance is often used in construction concrete.
Polycarboxylate superplasticizer is a new generation of water-reducing agent based on modified polycarboxylic acid.
Polycarboxylate (PCE) superplasticizers are known as high range water-reducing admixtures in concretes, such as ready-mix concretes, self-compacting concretes (SCC), ultra-high strength concretes (UHPC) and at the same time give an extended slump retention.
The polycarboxylic acid-based high-performance water-reducing agent, has truly designed an effective molecular structure based on the mechanism of dispersed cement. It has a super-dispersed type and can prevent concrete slump loss.