Mechanisms of Polycarboxylate Ether Superplasticizers: Influence on the Rheology and Hydration of Cement – A Review
Subject Areas :
Atefeh Nejadebrahim
1
*
,
Mohsen Najafi
2
,
Mohammad hosein Bagheri
3
1 - olymer Engineering Department, Qom University of Technology, P.O. Box: 1519-37195, Qom, Iran
2 - Polymer Engineering Department, Qom University of Technology, P.O. Box: 1519-37195, Qom, Iran
3 - Polymer Engineering Department, Qom University of Technology, P.O. Box: 1519-37195, Qom, Iran
Keywords: polycarboxylate Ether superplasticizer, Water Reduction, Cement, Rheology, Slump Retaining, chemical Structure,
Abstract :
polycarboxylate ether (PCE) superplasticizers, as the advanced generation of chemical admixtures for concrete, play a crucial role in improving rheological properties, enhancing fluidity, reducing the water-to-cement ratio, and ultimately increasing the mechanical strength and durability of concrete. In recent years, the use of these compounds has grown significantly due to the ability to precisely control their molecular structure and tailor their functional properties. Numerous studies have shown that the performance of PCE superplasticizers depends on factors such as the type and ratio of monomers used, final molecular weight, length and density of side chains, and reaction conditions.
This review provides a comprehensive discussion of recent advances in the design and synthesis of PCE polymers, their influence on the physical, chemical, and rheological characteristics of cementitious systems, and their role in the hydration process. The main mechanisms involved include electrostatic repulsion, steric hindrance, pressure release, enhanced wetting, and uniform dispersion of cement particles. The presence of functional groups such as carboxylates and polyether side chains in the polymer structure establishes an optimal balance between surface adsorption and dispersion stability. Moreover, modification of side-chain length and density, adjustment of molecular weight distribution, increased negative charge density, and improved compatibility with various types of cement are among the key strategies for enhancing their performance. Overall, understanding the relationship between chemical structure and rheological behavior paves the way for the development of more efficient and sustainable admixtures for next-generation concrete systems.
1. Tian, Hongwei, et al. "A new insight into the working mechanism of PCE emphasizing the interaction between PCE and Ca2+ in fresh cement paste." Construction and Building Materials 275 (2021): 122133.
2. Miao, C. W. "High performance admixture for concrete." Chemical Industry Press 4.5 (2009): 1-14.
3. Qian, Ye, et al. "Effect of polycarboxylate ether superplasticizer (PCE) on dynamic yield stress, thixotropy and flocculation state of fresh cement pastes in consideration of the Critical Micelle Concentration (CMC)." Cement and Concrete Research 107 (2018): 75-84.
4. Chen, Xingren, et al. "Enhanced adsorption and properties of TPEG-type superplasticizers modified by maleic anhydride: A perspective from molecular architecture and conformation." Materials and Structures 57.1 (2024): 4.
5. Gelardi, G., and R. J. Flatt. "Working mechanisms of water reducers and superplasticizers." Science and technology of concrete admixtures. Woodhead publishing, 2016. 257-278.
6. Yang, Yuzi, et al. "Interaction mechanisms between polycarboxylate superplasticizers and cement, and the influence of functional groups on superplasticizer performance: a review." Polymer Bulletin 81.12 (2024): 10415-10438.
7. Zheng, Tao, et al. "A novel branched claw-shape lignin-based polycarboxylate superplasticizer: Preparation, performance and mechanism." Cement and Concrete Research 119 (2019): 89-101.
8. Sakai, Etsuo, Akira Kawakami, and Masaki Daimon. "Dispersion mechanisms of comb‐type superplasticizers containing grafted poly (ethylene oxide) chains." Macromolecular Symposia. Vol. 175. No. 1. Weinheim: WILEY‐VCH Verlag GmbH, 2001.
9. Chuang, Po-Hsiang, et al. "Effect of side chain length on polycarboxylate superplasticizer in aqueous solution: A computational study." Polymers 11.2 (2019): 346.
10. Al-Neshawy, Fahim, Teemu Ojala, and Jouni Punkki. "Stability of air content in fresh concretes with PCE-based superplasticizers." Nord. Concr. Res 60 (2019): 145-158.
11. Yamada, Kazuo, et al. "Effects of the chemical structure on the properties of polycarboxylate-type superplasticizer." Cement and concrete research 30.2 (2000): 197-207.
12. Plank, Johann, et al. "Effectiveness of polycarboxylate superplasticizers in ultra-high strength concrete: the importance of PCE compatibility with silica fume." Journal of Advanced Concrete Technology 7.1 (2009): 5-12.
13. Sakai, E., J. K. Kang, and M. Daimon. "Action mechanisms of comb-type superplasticizers containing grafted polyethylene oxide chains." Special Publication 195 (2000): 75-90.
14. Kinoshita, M., and T. Nawa. "Effect of chemical structure on fluidizing mechanism of concrete superplasticizer containing polyethylene oxide graft chains." Special Publication 195 (2000): 163-180.
15. Xiang, Shuncheng, Yingli Gao, and Caijun Shi. "Progresses in synthesis of polycarboxylate superplasticizer." Advances in Civil Engineering 2020.1 (2020): 8810443.
16. Winnefeld, Frank, et al. "Effects of the molecular architecture of comb-shaped superplasticizers on their performance in cementitious systems." Cement and Concrete Composites 29.4 (2007): 251-262.
17. Li, Chong-Zhi, Nai-Qian Feng, and Rong-Jun Chen. "Effects of polyethlene oxide chains on the performance of polycarboxylate-type water-reducers." Cement and concrete research 35.5 (2005): 867-873.
18. Vickers Jr, Thomas M., et al. "Influence of dispersant structure and mixing speed on concrete slump retention." Cement and concrete Research 35.10 (2005): 1882-1890.
19. Plank, J., et al. "Synthesis and performance of methacrylic ester based polycarboxylate superplasticizers possessing hydroxy terminated poly (ethylene glycol) side chains." Cement and Concrete Research 38.10 (2008): 1210-1216.
20. Huang, Zhen, et al. "Preparing hyperbranched polycarboxylate superplasticizers possessing excellent viscosity-reducing performance through in situ redox initialized polymerization method." Cement and Concrete Composites 93 (2018): 323-330.
21. Miao, Changwen, et al. "Preparation method of hyperbranched polycarboxylic acid containing copolymer cement dispersant." U.S. Patent No. 9,175,122. 3 Nov. 2015.
22. Liu, Xiao, et al. "Novel designs of polycarboxylate superplasticizers for improving resistance in clay-contaminated concrete." Journal of industrial and engineering chemistry 55 (2017): 80-90.
23. Shao, Youzhe, et al. "Process design and optimization of VPEG-PCEs." IOP Conference Series: Earth and Environmental Science. Vol. 358. No. 3. IOP Publishing, 2019.
24. de Carvalho, José Maria Franco, et al. "Influence of high-charge and low-charge PCE-based superplasticizers on Portland cement pastes containing particle-size designed recycled mineral admixtures." Journal of Building Engineering 32 (2020): 101515.
25. Plank, Johann, Bernhard Sachsenhauser, and J. De Reese. "Experimental determination of the thermodynamic parameters affecting the adsorption behaviour and dispersion effectiveness of PCE superplasticizers." Cement and Concrete Research 40.5 (2010): 699-709.
26. Björnström, J., and S. Chandra. "Effect of superplasticizers on the rheological properties of cements." Materials and Structures 36 (2003): 685-692.
27. Ma, B., et al. "Influence of small molecular carboxylic acid polymer on adsorption mechanism of polycarboxylate superplasticizer." Bull Chin Ceram Soc 37.7 (2018): 2130-2135.
28. Shuaitao, W. E. N., and K. E. Kai. "Study on molecular structure and action mechanism of different polycarboxylate superplasticizer." New Building Materials/Xinxing Jianzhu Cailiao 47.2 (2020).
29. Fang, Yunhui, et al. "Study on the effect of main chain molecular structure on adsorption, dispersion, and hydration of polycarboxylate superplasticizers." Materials 16.13 (2023): 4823.
30. Erzengin, S. Gamze, et al. "Applications of sulfonate–carboxylate copolymers in cement." Advances in cement research 28.10 (2016): 630-642.
31. Liu, Jinzhi, et al. "Effect of molecular weight of slow-release Polycarboxylate Superplasticizer on the properties of cementitious system." Advances in Cement Research 30.7 (2018): 285-292.
32. Andersen, P. J., Della M. Roy, and James M. Gaidis. "The effect of superplasticizer molecular weight on its adsorption on, and dispersion of, cement." Cement and Concrete Research 18.6 (1988): 980-986.
33. Kong, Fan-rong, et al. "Effects of polycarboxylate superplasticizers with different molecular structure on the hydration behavior of cement paste." Construction and building materials 105 (2016): 545-553.
34. Lewis, Jennifer A., et al. "Polyelectrolyte effects on the rheological properties of concentrated cement suspensions." Journal of the American Ceramic Society 83.8 (2000): 1905-1913.
35. Shui, L. L., et al. "Research progress on working mechanism of polycarboxylate superplasticizer." J. Build. Mater 23 (2020): 64-69.
36. Jing, C., et al. "Synthesis of slightly cross-linked viscosity-reducing polycarboxylate superplasticizer and its influence on cement paste with low water-binder ratio." Mater Rep 36.09 (2022): 219-226.
37. MA, Bao-Guo, et al. "Retarding Mechanism of Polycarboxylic Acid Type Water reducing Agent." Journal of Changjiang River Scientific Research Institute 25.6 (2008): 93.
38. Qian, Shanshan, et al. "Synthesis, characterization and working mechanism of a novel polycarboxylate superplasticizer for concrete possessing reduced viscosity." Construction and Building Materials 169 (2018): 452-461.
39. Shui, L., et al. "Study on influence factors and dispersion rate of different types of superplasticizer." J Build Master 22.6 (2019): 853-859.
40. Yao, F., et al. "Synthesis, characterization and properties of two· arm hyperbranched polycarboxylate acid water-reducing agent." Polym Mater Sci Eng 38.2 (2022): 46-55.
41. Fan, Wei, et al. "A new class of organosilane-modified polycarboxylate superplasticizers with low sulfate sensitivity." Cement and concrete Research 42.1 (2012): 166-172.
42. He, Yan, et al. "Impacts of sulphates on rheological property and hydration performance of cement paste in the function of polycarboxylate superplasticizer." Construction and Building Materials 256 (2020): 119428.
43. He, Yan, et al. "Effect of carboxylic density on sulfate sensitivity of polycarboxylate superplasticizers." KSCE Journal of Civil Engineering 23 (2019): 5163-5172.
44. Han, Song, and Johann Plank. "Mechanistic study on the effect of sulfate ions on polycarboxylate superplasticisers in cement." Advances in Cement Research 25.4 (2013): 200-207.
45. Wu, Hui, et al. "Research on synthesis and action mechanism of polycarboxylate superplasticizer." Frontiers of Chemistry in China 2 (2007): 322-325.
46. He, Yan, et al. "Effects of PCEs with various carboxylic densities and functional groups on the fluidity and hydration performances of cement paste." Construction and Building Materials 202 (2019): 656-668.
47. Shu, Xin, et al. "Tailoring the solution conformation of polycarboxylate superplasticizer toward the improvement of dispersing performance in cement paste." Construction and Building Materials 116 (2016): 289-298.
48. Pourchet, Sylvie, et al. "Effect of the repartition of the PEG side chains on the adsorption and dispersion behaviors of PCP in presence of sulfate." Cement and Concrete Research 42.2 (2012): 431-439.
49. Zingg, Anatol, et al. "Interaction of polycarboxylate-based superplasticizers with cements containing different C3A amounts." Cement and Concrete Composites 31.3 (2009): 153-162.
50. Pourchet, Sylvie, et al. "Influence of PC superplasticizers on tricalcium silicate hydration." 12th International Congress on the Chemistry of Cement-ICCC 2007.
51. Chomyn, Claudia, and Johann Plank. "Impact of different pH-values of polycarboxylate (PCE) superplasticizer solutions on their dispersing effectiveness." Construction and Building Materials 246 (2020): 118440.
52. Plank, J., and B. Sachsenhauser. "Experimental determination of the effective anionic charge density of polycarboxylate superplasticizers in cement pore solution." Cement and Concrete Research 39.1 (2009): 1-5.
53. Borget, Pascal, et al. "Microstructural characterisation and behaviour in different salt solutions of sodium polymethacrylate-g-PEO comb copolymers." Colloids and Surfaces A: Physicochemical and Engineering Aspects 260.1-3 (2005): 173-182.
54. Tan, Hongbo, et al. "Adsorbing behavior of polycarboxylate superplasticizer in the presence of the ester group in side chain." Journal of Dispersion Science and Technology 38.5 (2017): 743-749.
55. Sun, Z., et al. "Slow-release effect of polycarboxylate superplasticizers with various functional groups." J Build Mater 25.3 (2022): 263-269.
56. Witt, Julia, and Johann Plank. "A novel type of PCE possessing silyl functionalities." Special Publication 288 (2012): 1-14.
57. He, Yan, Xiong Zhang, and R. D. Hooton. "Effects of organosilane-modified polycarboxylate superplasticizer on the fluidity and hydration properties of cement paste." Construction and Building Materials 132 (2017): 112-123.
58. Huang, Jian, et al. "Dispersing silica fume in cementitious materials by silane copolymerized polycarboxylate Superplasticizer: On the role of dispersion effectiveness as a function of silane concentration." Construction and Building Materials 326 (2022): 126832.
59. Qi, Huahui, et al. "Polycarboxylate superplasticizer modified by phosphate ester in side chain and its basic properties in gypsum plaster." Construction and Building Materials 271 (2021): 121566.
60. Stecher, J., and J. Plank. "Novel concrete superplasticizers based on phosphate esters." Cement and Concrete Research 119 (2019): 36-43.
61. Guan, Jianan, et al. "Effect of sulfonation modification of polycarboxylate superplasticizer on tolerance enhancement in sulfate." Construction and Building Materials 273 (2021): 122095.
62. Sakai, E., D. Atarashi, and Masaki Daimon. "Interaction between superplasticizers and clay minerals." Proceedings of the 6th International Symposium on Cement & Concrete. Vol. 2. 2006.
63. Jeknavorian, A. A., et al. "Interaction of superplasticizers with clay-bearing aggregates." Special Publication 217 (2003): 143-160.
64. Borralleras, Pere, et al. "Absorption conformations in the intercalation process of polycarboxylate ether based superplasticizers into montmorillonite clay." Construction and Building Materials 236 (2020): 116657.
65. Tan, Hongbo, et al. "Mechanism of intercalation of polycarboxylate superplasticizer into montmorillonite." Applied Clay Science 129 (2016): 40-46.
66. Werani, Matthias, and Lei Lei. "Influence of side chain length of MPEG–based polycarboxylate superplasticizers on their resistance towards intercalation into clay structures." Construction and Building Materials 281 (2021): 122621.
67. Lei, L., Y. Zhang, and R. Li. "Specific molecular design of polycarboxylate polymers exhibiting optimal compatibility with clay contaminants in concrete." Cement and Concrete Research 147 (2021): 106504.
68. Chen, Gang, et al. "A polycarboxylate as a superplasticizer for montmorillonite clay in cement: Adsorption and tolerance studies." Arabian journal of chemistry 11.6 (2018): 747-755.
69. Tan, Hongbo, et al. "Improvement of polyethylene glycol in compatibility with polycarboxylate superplasticizer and poor-quality aggregates containing montmorillonite." Journal of Materials in Civil Engineering 29.9 (2017): 04017131.
70. Li, Xiao-Kang, et al. "Enhancement clay tolerance of PCE by lignin-based polyoxyethylene ether in montmorillonite-contained paste." Journal of Industrial and Engineering Chemistry 49 (2017): 168-175.
71. Xu, Haijun, et al. "β-Cyclodextrin as pendant groups of a polycarboxylate superplasticizer for enhancing clay tolerance." Industrial & Engineering Chemistry Research 54.37 (2015): 9081-9088.
72. Lei, L., and J. Plank. "A concept for a polycarboxylate superplasticizer possessing enhanced clay tolerance." Cement and Concrete Research 42.10 (2012): 1299-1306.
73. Lei, Lei, et al. "Interaction between polycarboxylate superplasticizers and non-calcined clays and calcined clays: A review." Cement and Concrete Research 154 (2022): 106717.
74. Amaya, Toshihiko, et al. "Cement dispersant and concrete composition containing the dispersant." U.S. Patent No. 6,680,348. 20 Jan. 2004.