Hardening Mechanism on Hydration Process of Epoxy Latexes-Modified Cementitious Materials

Abstract

Abstract: Extreme environment and complex load conditions put forward higher requirements for the material properties of concrete. The method of improving concrete performance by modifying cement-based material with polymer has been widely used. To reveal the hardening mechanism of the hydration process of epoxy latexes-modified cementitious materials, the influence of epoxy latexes on the hydration process of cement hydration was studied by isothermal calorimetry, and the phase evolution of the cement clinker minerals and hydration products was tracked by in-situ XRD. The results show that the retardation effect of epoxy latexes on cement hydration is related to the interaction among epoxy particles, cement clinker minerals and hydration products, and the interaction effect becomes more obvious with time-dependent. When epoxy latexes are added into the cement paste, the heat-generation rate slows down, and the heat flow peak and cumulative heat generation reduce. Epoxy latexes can delay silicate reaction and aluminate reaction by inhibiting the dissolution of cement minerals (C₃S, C₃A and gypsum) and the precipitation of hydration products (ettringite and portlandite). The effect of epoxy latexes on cement hydration increases with the increase of its content.

Key words: retardation effect, epoxy latexes, cement clinker mineral, heat generation, isothermal calorimetry, in-situ XRD

CLC Number:

TQ172.79

JIANG Zhengshi, LI Pengfei, WANG Chengzhi, DU Sanlin, FENG Dongying. Hardening Mechanism on Hydration Process of Epoxy Latexes-Modified Cementitious Materials[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2022, 41(4): 1229-1236.

References

[1] 史庆轩,戎翀,陈云枭.FRP-钢-混凝土组合柱的研究现状[J].建筑材料学报,2019,22(3):431-439.
SHI Q X, RONG C, CHEN Y X. Research status of FRP-steel-concrete composite columns[J]. Journal of Building Materials, 2019, 22(3): 431-439 (in Chinese).
[2] 宋东方,刘富强,罗闯旦,等.聚合物改性水泥基材料力学性能研究[J].中国科技论文,2019,14(12):1311-1316.
SONG D F, LIU F Q, LUO C D, et al. Study on mechanical properties of cement materials modified by polymer[J]. China Sciencepaper, 2019, 14(12): 1311-1316 (in Chinese).
[3] 邓春林,范洪浩,张琴飞,等.船闸工程混凝土裂缝控制技术[J].水运工程,2015(3):123-127.
DENG C L, FAN H H, ZHANG Q F, et al. Cracks control of concrete for locks[J]. Port & Waterway Engineering, 2015(3): 123-127 (in Chinese).
[4] 钟世云,王培铭.聚合物改性砂浆和混凝土的微观形貌[J].建筑材料学报,2004,7(2):168-173.
ZHONG S Y, WANG P M. Study of morphology of polymer-modified mortar and concrete[J]. Journal of Building Materials, 2004, 7(2): 168-173 (in Chinese).
[5] 张爱勤,贾坚,刘芝敏,等.环氧树脂对混凝土抗盐冻能力的影响研究[J].硅酸盐通报,2019,38(4):1278-1283.
ZHANG A Q, JIA J, LIU Z M, et al. Influence of epoxy resin on salt scaling resistance of concrete[J]. Bulletin of the Chinese Ceramic Society, 2019, 38(4): 1278-1283 (in Chinese).
[6] LI P F, LU W, AN X H, et al. Effect of epoxy latexes on the mechanical behavior and porosity property of cement mortar with different degrees of hydration and polymerization[J]. Materials, 2021, 14(3): 517.
[7] 黄华,朱亮,黄敏,等.不同材料改性混凝土的性能研究及现状分析[J].硅酸盐通报,2018,37(6):1887-1896.
HUANG H, ZHU L, HUANG M, et al. Research and analysis on the performance of modified concrete with different materials[J]. Bulletin of the Chinese Ceramic Society, 2018, 37(6): 1887-1896 (in Chinese).
[8] 衡艳阳,赵文杰.聚合物改性水泥基材料的研究进展[J].硅酸盐通报,2014,33(2):365-371.
HENG Y Y, ZHAO W J. Research development of polymer modified cement based materials[J]. Bulletin of the Chinese Ceramic Society, 2014, 33(2): 365-371 (in Chinese).
[9] FERNÁNDEZ-RUIZ M A, GIL-MARTÍN L M, CARBONELL-MÁRQUEZ J F, et al. Epoxy resin and ground tyre rubber replacement for cement in concrete: compressive behaviour and durability properties[J]. Construction and Building Materials, 2018, 173: 49-57.
[10] 王茹,姚丽娟,王培铭.水泥基材料聚合物改性机理研究的最新进展[J].硅酸盐通报,2011,30(4):818-821.
WANG R, YAO L J, WANG P M. Recent research development on mechanism of polymer modification to cement-based materials[J]. Bulletin of the Chinese Ceramic Society, 2011, 30(4): 818-821 (in Chinese).
[11] 华先乐,王鑫鹏,胡晓霞,等.聚合物水泥混凝土的研究和应用进展[J].青岛理工大学学报,2020,41(5):133-140.
HUA X L, WANG X P, HU X X, et al. Advances in polymer cement concrete: research and application[J]. Journal of Qingdao University of Technology, 2020, 41(5): 133-140 (in Chinese).
[12] ZHANG Y Y, CHANG J, JI J. AH₃ phase in the hydration product system of AFt-AFm-AH₃ in calcium sulfoaluminate cements: a microstructural study[J]. Construction and Building Materials, 2018, 167: 587-596.
[13] CHANG J, ZHANG Y Y, SHANG X P, et al. Effects of amorphous AH₃ phase on mechanical properties and hydration process of C₄A₃$\bar{S}$-C$\bar{S}$H₂-CH-H₂O system[J]. Construction and Building Materials, 2017, 133: 314-322.
[14] CHEN C J, AN X H. Model for simulating the effects of particle size distribution on the hydration process of cement[J]. Computers & Concrete, 2012, 9(3): 179-193.
[15] LI Y, GUO Y C, LYU Z H, et al. Investigation of the effect of waterborne epoxy resins on the hydration kinetics and performance of cement blends[J]. Construction and Building Materials, 2021, 301: 124045.
[16] JANSEN D, GOETZ-NEUNHOEFFER F, STABLER C, et al. A remastered external standard method applied to the quantification of early OPC hydration[J]. Cement and Concrete Research, 2011, 41(6): 602-608.
[17] VALENTINI L, DALCONI M C, FAVERO M, et al. In-situ XRD measurement and quantitative analysis of hydrating cement: implications for sulfate incorporation in C-S-H[J]. Journal of the American Ceramic Society, 2015, 98(4): 1259-1264.
[18] JUILLAND P, GALLUCCI E, FLATT R, et al. Dissolution theory applied to the induction period in alite hydration[J]. Cement and Concrete Research, 2010, 40(6): 831-844.
[19] KONG X M, PAKUSCH J, JANSEN D, et al. Effect of polymer latexes with cleaned serum on the phase development of hydrating cement pastes[J]. Cement and Concrete Research, 2016, 84: 30-40.
[20] PLANK J, HIRSCH C. Impact of zeta potential of early cement hydration phases on superplasticizer adsorption[J]. Cement and Concrete Research, 2007, 37(4): 537-542.