Developing a Novel, Green, and Efficient Synthesis Method for Polycarboxylate Superplasticizers Through...

Area of Science:

• Materials Science
• Polymer Chemistry
• Civil Engineering

Background:

• Polycarboxylate superplasticizers (PCEs) are crucial polymer admixtures in cement and concrete.
• Developing novel, green, and energy-efficient synthesis methods for PCEs is essential for sustainable construction.
• Current aqueous solution polymerization methods for PCEs often result in low concentrations and high energy consumption.

Purpose of the Study:

• To develop a novel, green, and energy-efficient synthesis method for high-concentration PCEs (INPCEs) using mechanochemical internal mixing polymerization.
• To optimize reaction parameters including temperature, speed, time, and reactant concentrations for INPCE synthesis.
• To compare the performance and energy consumption of INPCEs with conventionally synthesized PCEs (TPCE).

Main Methods:

• Mechanochemical internal mixing polymerization was employed for the first time to synthesize PCEs.
• Orthogonal experimental design was used to determine optimal reaction conditions (temperature, speed, time).
• Fourier transform infrared spectroscopy (FT-IR) and gel permeation chromatography (GPC) were used for molecular structure characterization.
• Performance evaluation involved testing cement paste fluidity and comparing INPCEs with TPCE.

Main Results:

• Optimal synthesis conditions were identified as 60 °C, 70 R/min, and 60 min.
• The synthesized INPCEs achieved a concentration of >99.00 wt%, significantly higher than TPCE (39.73 wt%).
• INPCEs exhibited initial fluidity of 312.5 mm at 0.20 wt% dosage, with dispersion and retention properties comparable to TPCE.
• The mechanochemical method demonstrated substantially lower energy consumption compared to aqueous solution polymerization.

Conclusions:

• Mechanochemical internal mixing polymerization is a viable and energy-efficient method for producing high-concentration PCEs.
• The developed INPCEs offer comparable performance to traditional PCEs with significantly reduced energy requirements.
• This approach holds potential for reducing the overall energy consumption in the concrete industry.