摘要
从聚合物改性水泥的水化速率、水化热及水化生成物三方面讨论了聚合物对水泥水化的影响。水泥溶液ｐＨ 值和电导率及水泥凝结时间的研究结果表明，非离子聚合物聚丙烯酰胺、聚乙烯醇减慢水泥的初期水化，具有缓凝作用，而阴离子聚合物水解聚丙烯酰胺、聚丙烯酸、磺化聚丙烯酰胺及磺化聚苯乙烯则加速水泥的初期水化，具有促凝作用；水化放热测量结果表明，掺加聚合物均滞缓水泥的后期水化；ＸＲＤ 分析表明，ＨＰＡＭ 抑制水泥中晶体的早期生长，有利于晶体后期形成。在水泥中掺加１ ％ ～２ ％ 的ＨＰＡＭ、ＰＡＡ、ＳＰＳ或ＰＶＡ，抗折强度和抗压强度均有明显提高。
In this paper, the influences of several water-soluble polymers on the hydration of cement were studied. The measurements of pH value, conductivity, and cement setting time indicate that the nonionic polymers (PAM , PVA ) retard the hydration rate at initial period of cement setting, while anionic polymers ( HPAM , PAA , SPAM and SPS ) accelerate this process. The hydration thermograms show that all these polymers slow down hydration at later period of cement setting. XRD analysis reveals that HPAM restrains the crystallization of Ca(OH) 2 at early period of hydration but benefits the formation of larger crystals of Ca(OH) 2 at later stage. The bending and compressive strengths of cements modified by water-soluble polymers were increased remarkably, and the mechanism was discussed.
出处
《功能高分子学报》
CAS
CSCD
1999年第3期276-280,共5页
Journal of Functional Polymers
基金
四川省科委应用基础研究基金
