some problems in the application of polycarboxylate superplasticizerii
Compatibility of polycarboxylate superplasticizer with other admixtures.
Beijing Dongke United Technologies Co.,Ltd.
The polycarboxylic acid water reducing agent is an effective water reducing agent and cement dispersant in cement concrete applications. It is widely used in roads, bridges, towers, tunnels, skyscrapers and other projects.
The water-reducing agent is environmentally friendly, non-flammable, explosive and can be transported safely in trains and cars.
Polycarboxylic acid superplasticizers can be divided into two categories according to the different backbone structure: one type uses acrylic acid or methacrylic acid as the backbone and graft polyethers with different side chain lengths.
Others are polyethers whose primary bond is maleic anhydride and have different side chain lengths. From this, various high-performance pce superplasticizer products with different properties have been derived.
Prior to the formation of the polycarboxylate water reducing agent, it was necessary to regenerate the supernatants from the polycarboxylate supernatants.
It has the advantage of low dosage, good droplet retention, low shrinkage of concrete, high molecular structure control and high yield potential. Significant advantages such as the absence of formaldehyde in the process.
For the synthesis of a water-reducing agent from a polycarboxylate water-reducing agent, the design of the molecular structure, including the backbone group, the side chain density, and the side chain length in the molecule, is very important.
The synthetic methods mainly include an in situ graft polymerization method, first a polymerization method and then a functionalization method and a direct copolymerization method for monomers.
In many concrete projects, traditional high-grade concretes, such as the naphthalene series, are increasingly unable to meet project requirements due to technical performance constraints.
A new generation pce superplasticizer that has attracted a lot of attention at home and abroad, a polycarboxylate water-reducing agent, a high-performance water-reducing agent because it has really developed an efficient molecular structure based on a distributed cement mechanism.
It is highly dispersed. art and can prevent concrete from buckling without significant delay, because at low concentrations it provides a better softening effect, good flow retention, a high degree of freedom of cement to adapt to various molecular synthesis techniques and plenty of room for high concrete shrinkage.
Very low impurity content, other performance , good strength development, excellent durability and effective damage – reducing water – borne polycyclic acid.
Arboxyl has good overall technical advantages and environmental protection properties that meet the requirements of modern concrete technology.
Therefore, pce superplasticizer-effective water-reducing agents are gradually becoming a popular mixture for the production of high-performance concrete.
Polycarboxylic acid additives are reported to account for more than 80% of all high performance additive products in Japan and more than 50% in North America and Europe.
In my country, polycarboxylate water-reducing agents have only been successful in the Three Gorges Dam, the Sutong Bridge, the Tianwan Nuclear Power Plant, the Beijing-Shanghai High-Speed Rail Network, and other major national water protection systems, bridges, nuclear power, and railways. Projects with significant results.
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.