聚合物对砂浆热老化后防水及力学性能的影响

摘要/Abstract

摘要： 将可再分散沥青粉末(EAP)、醋酸乙烯酯-乙烯共聚物(VAE)乳胶粉、苯乙烯-丙烯酸丁酯共聚物(SBA)乳液作为外加剂分别掺入水泥砂浆,通过热处理前后的吸水率测试、胶砂强度测试和微观形貌分析,研究了不同聚合物对水泥砂浆在70 ℃的耐热老化性能的影响。结果表明:试验采用的聚合物均可降低砂浆吸水率,且吸水率随聚合物掺量的增加而降低。SBA乳液的成膜性能优于粉体聚合物,因此SBA改性砂浆的表面防水效果最佳;两种可再分散聚合物粉末对比,同期热老化后EAP对砂浆防水改性效果优于VAE。经热老化后,沥青组分高温下具有一定的黏流性,EAP改性砂浆热老化后抗压强度降低,随EAP掺量增加,抗折强度先升高后降低,其强度变化主要体现为沥青组分在高温下的作用特点,VAE改性砂浆及SBA改性砂浆热老化初期聚合物膜结构阻碍水分迁移,热老化后期柔性的聚合物膜结构破坏造成强度高于热老化前的强度,其强度变化主要体现为传统聚合物改性砂浆的特点。

关键词: 聚合物, 水泥砂浆, 耐热老化性能, 沥青粉末, VAE, SBA

Abstract: In this paper, emulsified asphalt powder (EAP), VAE redispersible polymer powder, and SBA emulsion as admixtures were mixed into the cement mortar. Cement mortar strength, water absorption and SEM analysis before and after heat treatment were used to investigate the effect of addition of the three polymers on heat aging resistance of cement mortar at 70 ℃. The results show that the addition of three polymers can all decrease the water absorption, and the water absorption decreases with the increase of polymer content. The film-forming property of SBA emulsion is better than that of redispersible polymer powder, so its modified-mortar has the best surface waterproof effect. Compared with VAE, the effect of EAP on mortar waterproofing modification is better after heat treatment. After heat treatment, asphalt component has certain viscous flow at high temperature, and the compressive strength of EAP-modified mortar decreases after heat treatment, and the flexural strength increases first and then decreases with the increase of EAP admixture, and its strength changes mainly reflect the characteristics of asphalt components under high temperature, while those VAE-modified mortar and SBA-modified mortar mainly reflect the characteristics of traditional polymer modified mortar, the polymer film structure hinders moisture migration at the early stage of heat treatment, and the flexible polymer film structure breaks down at the later stage of heat treatment causing strength higher than that before thermal aging.

Key words: polymer, cement mortar, heat aging resistance, emulsified asphalt powder, VAE, SBA

中图分类号:

TU528

张娜, 孙倩, 张鹏宇, 王冬梅, 王琴. 聚合物对砂浆热老化后防水及力学性能的影响[J]. 硅酸盐通报, 2023, 42(8): 2703-2711.

ZHANG Na, SUN Qian, ZHANG Pengyu, WANG Dongmei, WANG Qin. Effects of Polymers on Waterproofing and Mechanical Properties of Mortar after Heat Treatment[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2023, 42(8): 2703-2711.

参考文献

[1] 兰明章, 王亚丽. 干混砂浆耐久性测试方法的研究[C]//2004年中国国际建筑干混砂浆生产应用技术研讨会论文集, 2004: 271-274.
LAN M Z, WANG Y L. Research of measurements on dry-mortar durability[C]//2004 China International Exposition & Forum on Dry Mix Mortars Processes & Application, 2004: 271-274 (in Chinese).
[2] 彭家惠, 毛靖波, 张建新, 等. 可再分散乳胶粉对水泥砂浆的改性作用[J]. 硅酸盐通报, 2011, 30(4): 915-919.
PENG J H, MAO J B, ZHANG J X, et al. Application of redispersion emulsoid powder in cement mortar[J]. Bulletin of the Chinese Ceramic Society, 2011, 30(4): 915-919 (in Chinese).
[3] 潘文学, 王友贵. XPS板外墙外保温技术性能及应用[J]. 建筑技术, 2006, 37(10): 736-739.
PAN W X, WANG Y G. Technical properties of XPS plate used for outer insulation of external wall and its application[J]. Architecture Technology, 2006, 37(10): 736-739 (in Chinese).
[4] 项道阳, 路永华, 章银祥. 聚合物抹面砂浆耐候性试验研究破坏机理分析[J]. 工业建筑, 2009, 39(9): 95-98.
XIANG D Y, LU Y H, ZHANG Y X. Analysis of damage mechanism of polymer finishing mortar under weathering test[J]. Industrial Construction, 2009, 39(9): 95-98 (in Chinese).
[5] 章银祥. 外墙外保温系统的工况监测与研究[J]. 建筑科学, 2010, 26(6): 25-27+68.
ZHANG Y X. Monitoring and analysis on working conditions of outer-wall external thermal insulation system[J]. Building Science, 2010, 26(6): 25-27+68 (in Chinese).
[6] 徐海源, 沙建芳, 刘建忠, 等. 水泥基瓷砖粘结剂耐热老化性能影响因素研究[J]. 新型建筑材料, 2016, 43(3): 29-32.
XU H Y, SHA J F, LIU J Z, et al. Studies of the heat-aging resistance performance for cement-based tile adhesive[J]. New Building Materials, 2016, 43(3): 29-32 (in Chinese).
[7] 李斌, 赵旭章, 晋强, 等. 粉煤灰掺量对钢渣蓄热水泥砂浆耐热性能的影响[J]. 粉煤灰综合利用, 2021, 35(2): 85-91.
LI B, ZHAO X Z, JIN Q, et al. Influence of fly ash content on heat resistance of steel slag thermal storage cement mortar[J]. Fly Ash Comprehensive Utilization, 2021, 35(2): 85-91 (in Chinese).
[8] 熊杰, 萧庆亮, 许淑燕, 等. AFRP-水泥砂浆体系的耐热性能[J]. 纺织学报, 2005, 26(1): 59-61.
XIONG J, XIAO Q L, XU S Y, et al. Heat resistance of AFRP-cement mortar[J]. Journal of Textile Research, 2005, 26(1): 59-61 (in Chinese).
[9] 丁向群, 张冷庆, 冀言亮, 等. 聚合物改性粘结砂浆的性能研究[J]. 硅酸盐通报, 2014, 33(5): 1040-1044.
DING X Q, ZHANG L Q, JI Y L, et al. Study on performance of polymer-modified bonding mortar[J]. Bulletin of the Chinese Ceramic Society, 2014, 33(5): 1040-1044 (in Chinese).
[10] VAN TIEN P. Relationship between the adhesive properties and rheological behaviors of fresh mortars[D]. Cachan: Ecole Normale Superieure de Cachan, 2012.
[11] 周延翱. 水泥-乳化沥青交互作用机理及其复合胶凝材料性能研究[J]. 山东交通科技, 2022(1): 16-18+21.
ZHOU Y A. Study on the mechanism and performance investigation of cementemulsified asphalt composite[J]. Shandong Jiaotong Keji, 2022(1): 16-18+21 (in Chinese).
[12] 潘硕, 王琴, 詹达富, 等. 乳化沥青粉改性水泥砂浆性能及微观结构研究[J]. 硅酸盐通报, 2019, 38(8): 2622-2630.
PAN S, WANG Q, ZHAN D F, et al. Properties and microstructure of emulsified asphalt powder modified cement mortar[J]. Bulletin of the Chinese Ceramic Society, 2019, 38(8): 2622-2630 (in Chinese).
[13] ZHAO G R, WANG P M, ZHANG G F. Effect of latex film distributions on flexibility of redispersible polymer powders modified cement mortar evaluated by SEM[J]. Advanced Materials Research, 2015, 1129: 331-338.
[14] WANG M, WANG R M, ZHENG S R, et al. Research on the chemical mechanism in the polyacrylate latex modified cement system[J]. Cement and Concrete Research, 2015, 76: 62-69.
[15] 赵丽杰. 聚合物砂浆柔韧性的表征方法与提高途径研究[D]. 北京: 北京建筑工程学院, 2012.
ZHAO L J. Study on characterization methods and ways to improve of the polymer mortar's flexibility[D]. Beijing: Beijing Institute of Civil Engineering and Architecture, 2012 (in Chinese).