Journal of the Korean Ceramic Society (한국세라믹학회지)

The Korean Ceramic Society (한국세라믹학회)
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Effects on the Properties of Cement Mortar with Various Molecular Structures of Polycarboxylate-Type Superplasticizers

폴리카복실레이트계 고유동화제의 분자구조가 시멘트 모르타르의 물성에 미치는 영향

  • Song, Jong-Taek (Department of Materials Science and Engineering, Dankook University) ;
  • Ryu, Ho-Seok (Department of Materials Science and Engineering, Dankook University)
  • Published : 2004.04.01
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Abstract

This paper presents the experimental results on the properties of the cement mortar with polycarboxylate-type superplasticizers PCA) which were synthesized by different mole ratio of methoxypoly(ethyleneglycol)monomethacrylate (MPEGMAA) and methacrylic acid (MAA) and by different length of polyethyleneoxide (PEO). As the PEO chain was longer and mole ratio of [MPEGMAA]/[MAA] was lower, the fluidity of cement mortar was better. The setting time of mortar with PCA was retarded, and as PEO chain was shorter and [MPEGMAA]/[MAA] was lower, it was more retared. Espeacially, when the molecular weight of MPEGMAA was 475(repeat unit of ethylene oxide=l0), the degree of retardation was the highest of them. The surface tensions of PCA solutions were lower than that of water due to the effect of PEO chain, and also the pore size distribution of cement mortar was influenced by it. The pores in cement mortar with PCA at 28 days were macropores in the range of 7 to 370$\mu\textrm{m}$, and accordingly, the densities and compressive strengths of mortar were lower than those of OPC mortar.

메톡시폴리에틸렌글리콜모노메타크릴레이트(MPEGMAA)와 메타크릴산(MAA)의 몰비와 MPEGMAA의 폴리에틸렌옥사이드(PEO)의 길이를 변화시켜 합성한 폴리카복실레이트계 고유동화제(PCA)를 시멘트 모르타르에 첨가한 경우. 그 물성에 미치는 영향에 대하여 조사하였다. PEO의 길이가 긴 경우 ［MPEGMAA］/［MAA］ 몰비가 낮을수록 모르타르의 유동성은 향상되었다. PCA를 첨가했을 때 응결시간은 지연되며, PEO의 길이가 짧고 ［MPEGMAA］/［MAA］ 몰비가 낮을수록 응결은 더 지연되었다. 특히 MPEGMAA의 분자량이 475인 경우(에틸렌옥사이드 반복단위는 10이다) 응결시간의 지연이 가장 컸다. PCA 분자내 존재하는 PEO의 영향으로 표면장력은 크게 낮아지며, 몰탈의 기공크기분포를 크게 변화시쳤다. PCA에 의해 생성되는 기공은 대부분 7∼370$\mu\textrm{m}$ 범위의 거대 기공이며, 이 기공들에 의해 몰탈의 밀도와 압축강도가 낮아지게 되었다.

Keywords

References

  1. Conc. J. v.36 no.4 The International Development Situation of Superplasticizer (High-Range Water-Reducing AE Agent, High-Range Water-Reducing Agent) K.Yamada
  2. Proceedings of the 7th International Congress on the Chemistry of CementⅣⅣⅣ Effect of Superplasticizer on the $C_3A$ Hydration F.Massazza;U.Costa
  3. 4th International Symposium on Advance in Concrete Technology v.SP179 Influence of the Sulfate Level in the Clinker Phase on the Performance of Superplasticized Concretes L.Coppola;R.Troli;P.Zaffaroni;M.Collepardi
  4. Cement and Conc. Res. v.27 no.1 The Role of Steric Repulsive Force in the Dispersion of Cement Particles in Fresh Paste Prepared with Organic Admixture H.Uchikawa;S.Hanehara;D.Sawaki https://doi.org/10.1016/S0008-8846(96)00207-4
  5. 5th International Conference on Superplastickizers and othe Chemical Admixtures in Concerete v.SP173 Fluidizing Mechanism and Application of Polycarboxylated-Based Superplasticizers A.Ota;Y.Sugiyama;T.Tanaka
  6. J. Am. Ceram. Soc. v.80 no.10 Role of Steric Hindrance in the Performance of Superplasticizers for Concrete K.Yoshioka;E.Sakai;M.Daimon;A.Kitahara https://doi.org/10.1111/j.1151-2916.1997.tb03169.x
  7. 5th International Conference on Superplasticizers and other Chemical Admixtures in Concrete v.SP173 Chemical Structures and Performance of New High-Range Water-Reducing and Air-Entraining Agents M.Shonaka;K.Kitagawa;H.Satoch;T.Izumi;T.Mizunuma
  8. J. of Adv. Conc. Tech. v.1 no.1 Molecular Structure and Dispersion-Adsorption Machanisms of Comb-Type Superplasticizers Used in Japan E.Sakai;K.Yamada;A.Ohta https://doi.org/10.3151/jact.1.16
  9. JCA Proceeding of Cement & Conc. v.47 Chemical Structure and Performance of a New Type High-Range Water-Reducing Agent for Ultra High Strength Concrete M.Kinoshta;T.Yonezawa;Y.Yuki
  10. JCA Proceeding of Cement & Conc. v.47 Hydrolysis Mechanism of Crosslinked Polymer Based Superplasticizer with Improved Dispersibility A.Ohta;T.Furusawa;T.Tsuchitani
  11. Cement Sci. and Conc. Tech. v.52 Study on the Dispersing Mechanism of Polycarboxylate-Based Dispersant A.Ohta;T.Umoto
  12. Cement and Conc. Comp. v.20 Chemical Admixturecement Interactions: Phenomenology and Physico-Chemical Concepts C.Jolicoeur;M.A.Simard https://doi.org/10.1016/S0958-9465(97)00062-0
  13. Cement and Conc. Res. v.14 Influence of $CaSO_v2H_2O,CaSO_4,$ and Middot; 1/2H_2O and CaSO_4 on the Initial Hydration of Clinker having Different Burning Degree H.Uchikawa;S.Uchida;K.Ogawa;S.Hanehara https://doi.org/10.1016/0008-8846(84)90027-9
  14. Cement and Conc. Res. v.30 Effects of the Chemical Structure on the Properties of Polycarboxylate-Type Superplasticizer K.Yamada;T.Takahashi;S.Hanehara;M.Matsuhisa https://doi.org/10.1016/S0008-8846(99)00230-6
  15. Cement and Conc. Res. v.25 no.4 Modelling of the Transition Zone Porosity B.Bourdette;E.Ringot;J.P.Ollivier https://doi.org/10.1016/0008-8846(95)00064-J
  16. Cement and Conc. Res. v.15 Investigation on the Relationship between Porosity, Structure and Strength of Hydrated Portland Cement Paste.(Ⅱ)Effect of Pore Structure and of Degree of Hydration I.Odler;M.Robler https://doi.org/10.1016/0008-8846(85)90113-9
  17. Cement and Conc. Res. v.15 Investigation on the Relationship between Porosity, Structure, and Strength of Hydrated Portland Cement Pastes. (Ⅰ) Effect of Porosity M.Robler;I.Odler https://doi.org/10.1016/0008-8846(85)90044-4

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