Synthesis and Performance of Polycarboxylate Superplasticizer Based on a Novel Redox System of Manganese Dioxide/Acid

Authors

  • Siyong CHENG Zibo Transportation Construction Development Center
  • Xintang WANG Shandong Hi-Speed Infrastructure Construction Co., Ltd.
  • Si WU Shandong Hi-Speed Engineering Test Co., Ltd.
  • Luyan WANG University of Jinan https://orcid.org/0000-0003-4605-2490

DOI:

https://doi.org/10.5755/j02.ms.40831

Keywords:

manganese dioxide, acid, cement, dispersion, superplasticizer

Abstract

This study aims to develop a novel redox system based on manganese dioxide (MnO₂)/acid for synthesizing polycarboxylate superplasticizers (MPCE) via solution copolymerization of acrylic acid (AA) and methallyl polyoxyethylene ethers (TPEG). The performance of MPCE synthesized using MnO₂ combined with different acids (citric acid, tartaric acid, oxalic acid) was compared with two conventional redox systems: ascorbic acid (VC)/H₂O₂ and ammonium persulfate. The MnO₂/citric acid system proved most effective, attributed to its one-step reaction to generate primary free radicals. Optimal reaction conditions were determined as a molar ratio of AA to TPEG (Mn=2400) of 3.5:1.0 and [MnO₂]:[citric acid] of 1:1. The longer side chains of MPCE enhanced adsorption on cement particles and dispersing performance via steric hindrance. Cement paste containing MPCE-2400 showed superior dispersing ability, retention capacity, clay resistance, and hardened mechanical properties. The findings highlight the critical role of the MnO₂/acid redox system in optimizing MPCE synthesis.

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Published

2025-06-19

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Section

Articles