Materials Transactions Online

Materials Transactions, Vol.53 No.03 (2012) pp.553-558
© 2012 The Japan Institute of Metals

Effects of Grafting Densities of Comb-Like Copolymer on the Dispersion Properties of Concentrated Cement Suspensions

Jiaping Liu1, Qianping Ran1, 2, Changwen Miao1 and Min Qiao2

1State Key Laboratory of High Performance Civil Engineering Materials (Jiangsu Research Institute of Building Science), Nanjing, 210008, P. R. China
2Jiangsu Bote New Materials Co. Ltd., Nanjing, 210008, P. R. China

Effects of grafting densities of comb-like copolymer on the dispersion properties of concentrated cement suspensions are investigated systemicly in this paper. For comb-like copolymers the adsorbed amount increases at the same dosages as the grafting density decreases, while the efficiency of dispersion is improved by increasing the grafting densities. Based on the theory of Flatt at level of scaling law, the molecule size and the occupied surface area of the comb-like polymers with different grafting densities are calculated. The comb-like polymers with higher grafting density has bigger molecular size. For comb-like polymer dispersant, the steric repulsion provided by the side chains is the main drive of the dispersion, so the Flory energy is employed to explore the relationship between steric repulsion and grafting density. The calculation tells us that higher grafting density results in higher Flory energy which represents stronger steric repulsion. The calculation method based on the scaling law and Flory theory is successfully used to interpret the dispersion mechanism, and it is anticipated that this method can be applied to explain the effect of other parameters of PCE comb-like polymers on the dispersion properties of cement suspensions, ceramics suspensions, slurries and so on.

(Received 2011/11/07; Accepted 2011/12/14; Published 2012/02/25)

Keywords: comb-like copolymer, grafting density, dispersion, cement, molecular size, steric repulsion

PDF(Free)PDF (Free) Table of ContentsTable of Contents

REFERENCES

  1. K. Yoshioka, E. Sakai, M. Daimon and A. Kitahara: J. Am. Ceram. Soc. 80 (1997) 2667-2671.
  2. K. Yamada, S. Hanehara and K. Honma: Cement Concrete Res. 30 (2000) 197-207.
  3. K. Yoshioka, E. Tazawa, K. Kawai and T. Enohata: Cement Concrete Res. 32 (2002) 1507-1513.
  4. Q. P. Ran, P. Somasundaran, C. W. Miao, J. P. Liu, S. S. Wu and J. Shen: J. Disper. Sci. Technol. 31 (2010) 790-798.
  5. J. Plank, D. Vlad, A. Brandl and P. Chatziagorastou: Cement Int. 3 (2005) 101-110.
  6. H. Uchikawa, S. Hanehara and D. Sawaki: Cement Concrete Res. 27 (1997) 37-50.
  7. Q. P. Ran, P. Somasundaran, C. W. Miao, J. P. Liu, S. S. Wu and J. Shen: J. Colloid Interface Sci. 336 (2009) 624-633.
  8. F. Winnefeld, S. Becker, J. Pakusch and T. Gotz: Cement Concrete Compos. 29 (2007) 251-262.
  9. L. Ferrari, J. Kaufmann, F. Winnefeld and J. Plank: Cement Concrete Res. 41 (2011) 1058-1066.
  10. G. Ferrari, T. Cerulli, P. Clemente, M. Dragoni, M. Gamba and F. Surico: 6th CANMET/ACI International Conference Superplasticizers and Other Chemical Admixtures in Concrete, ed. by V. M. Malhotra, (Am. Concrete Inst., USA, 2000) SP-195, pp. 505-520.
  11. T. Nawa: J. Adv. Concr. Technol. 4 (2006) 225-232.
  12. G. H. Kirby and J. A. Lewis: J. Am. Ceram. Soc. 87 (2004) 1643-1652.
  13. J. Plank and B. Sachsenhauser: J. Adv. Concr. Technol. 4 (2006) 233-239.
  14. R. J. Flatt, I. Schober, E. Raphael, C. Plassard and E. Lesniewskat: Langmuir 25 (2009) 845-855.
  15. C. Gay and E. Raphael: Adv. Colloid Interface Sci. 94 (2001) 229-236.
  16. M. Kinoshita, T. Nawa and M. Iida: 6th CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete, ed. by V. M. Malhotra, (Am. Concrete Inst., USA, 2000) SP-195, pp. 163-180.
  17. J. S. Pedersen and C. Sommer: Prog. Colloid Polym. Chem. 130 (2005) 27-36.


[JIM HOME] [JOURNAL ARCHIVES]

© 2012 The Japan Institute of Metals
Comments to us : editjt@jim.or.jp