High-performance superplasticizer based on chitosan
High-performance superplasticizer based on chitosan 7.3.1. Preparation of the chitosan superplasticizer The preparation of a high-performance superplasticizer using chitosan modifies its molecular structure by a chemical reaction based on hydroxyl and amino groups.
New Generation Amphoteric Comb-like Copolymer
comb-like superplasticizer has such remarkablebenefitsinpractice,anionic comb-likepolymeradmixtureshave the shortcoming of low saturation dosage. Above the saturation point, the dispersing effect or water reducing rate cannot be improved7.Hence, this impedes the development of ultra high-strength concrete with low water
Synthesis and Performance of Polycarboxylic Acid
A new type of polycarboxylic acid superplasticizer (G18-PCEs) containing crosslinked linkage was synthesized by the method of the first esterification and then polymerization. Its monomer and polymer structure were confirmed by 1H nuclear magnetic resonance (NMR) spectroscopy and High-performance liquid chromatography.
Effect of Superplasticizers to Enhance the Properties
The experiments were classified into two phases: the first phase focused on the effects of superplasticizer admixture on workability and compressive strength, and the second phase determined the...
Selection of Superplasticizers for High-Performance Concrete
The first moment consumption of Superplasticizer molecules after the mixing is qualified as the cement/Superplasticizer compatibility. It is very difficult to make high-performance concrete with a very low water-cement ratio, that it will still have a slump value of 50mm 30 minutes with an initial slump value of 200mm.
- Can a new superplasticizer reduce shrinkage of concrete containing montmorillonite?
- A type of novel superplasticizer (PCA-SF) with a snowflake-shaped side chain (Fig. 17) decreases thickness of the area (~0.9 μm) in comparison with the conventional PCE (~2.0 μm) and increases the compatibility between clays and PCA-SF. The introduction of PCA-SF showed better control on drying shrinkage of concrete containing montmorillonite.
- Why do cross-linked superplasticizers increase compressive strength?
- After 3, 7 and 28 d, the compressive strength of the cement mortar was improved with increases of molecular weight of the cross-linker in the cross-linked superplasticizers due to the elevation of ethoxy content. 1. Introduction Superplasticizers (SPs) are essential components of concrete .
- Are cross-linked superplasticizers good?
- The fluidity and fluidity retention tests, adsorption performance and scanning electron microscope tests showed that the cross-linked superplasticizers offered good dispersing effects and excellent slump performance.
- What is a comb shaped polycarboxylate SP?
- Comb-shaped polycarboxylate SPs have been widely used because they can effectively reduce the viscosity of concrete and improve the fluidity of cement paste .
- What is a superplasticizer in concrete?
- Superplasticizers (SPs) are essential components of concrete . They not only can reduce the amount of water required to form concrete, but can also improve the compressive strength .
- What is a star shaped superplasticizer?
- Star-shaped (SPCE) superplasticizer can be synthesized by esterification to obtain the core of structure, followed by polymerization . SPCE can form a large stereoscopic structure and a thick water film to disperse cement particles effectively and prevent flocculation.