Preparation and properties of allyl ether-based
Polycarboxylate ether (PCE) superplasticizer possesses outstanding characteristics, such as better slump adjust- ment, higher water reduction rate, and lower dosage.1,2It is a new type of superplasticizer commonly used in advanced concrete in recent years.
Progresses in Synthesis of Polycarboxylate Superplasticizer
The prerequisite to synthesize PCE was to prepare new macromonomers with controlled molecular mass, adjustable hydrophilic-lipophilic groups, long-chain alkyl groups, and large terminal hydroxyl groups as well. Structural modifications in the molecular scale of polycarboxylate superplasticizer (PCE) would lead to changes in properties of dispersion and water retention as well as enhancement in
Study on performance stability of Polycarboxylate
The effects of initial dropping temperature, amount of ferrous sulfate and dropping time on the performance of Polycarboxylate Superplasticizer were studied, and the measures to maintain the...
Synthesis, characterization and mechanism of polycarboxylate
Two kinds of slump-retaining polycarboxylate superplasticizer with different molecular structures were synthesized via maleic anhydride (MAH), polyethylene glycol monoallyl ether (APEG) and hydroxyethyl acrylate (HEA)/ethyl acrylate (EA) according to molecular structure design principle.
Synthesis of New Polyether Polycarboxylate Superplasticizer
good but the fluidity conservation was not as well as the lower molecular weight. The optimum raw material proportion to synthesize the new polyether polycarboxylate superplasticizer was as follows: XPEG ︰MAn︰MAS was 2︰4︰1.5, XPEG molecular weight was 1 600. 3.2 Effect of the radical initiator According to action mechanism of the
- What are viscosity reducing polycarboxylate superplasticizers (Jn-PCE)?
- In this study, we synthesized a series of viscosity-reducing polycarboxylate superplasticizers (JN-PCE) utilizing allyl polyethylene glycol ether (APEG), acrylic acid (AA), and sodium methallyl sulfonate (SMAS) as raw materials through the process of free radical polymerization.
- What is polycarboxylate superplasticizer (PCE)?
- As one important auxiliary, superplasticizers have attracted lots of attention in the concrete and building materials field. Specially, polycarboxylate superplasticizer (PCE) has been widely applied due to its relatively low doping amount, high water reducing rate and environmental friendliness property.
- Does water-cement ratio affect viscosity reducing capacity of a polycarboxylate superplasticizer?
- At a water-cement ratio of 0.18, the Marsh time of the JN-type PCE was reduced by 40% while maintaining the same fluidity, thereby underscoring the effective viscosity-reducing capabilities of the synthesized polycarboxylate superplasticizer. No potential conflict of interest was reported by the author (s).
- Does carboxyl density affect PCE adsorption capacity?
- Within a certain range, PCE with higher carboxyl density has higher adsorption capacity and tolerance to sulfate ions; (2) Compared with random PCE, block PCE can be adsorbed on the surface of cement particles faster.
- Are superplasticizers effective in low water-cement ratio systems?
- Subsequent evaluations of surface tension, fluidity, adsorption performance, and Marsh time demonstrated that these superplasticizers exhibited commendable dispersion and remarkable viscosity-reducing properties within a low water-cement ratio system.
- Why do polycarboxylate polymers have low anion charge density?
- As shown in Fig. 2, Plank et al. reported that in the pore solution of cement, the main chain of polycarboxylate polymer will be wrapped by cation cloud formed by counter-ion condensation, thus exhibiting low anion charge density and reducing their adsorption and dispersion capacity.
