新型含苯环聚羧酸系减水剂的制备与性能

Preparation and Properties of New Type Polycarboxylate Superplasticizer Included Benzene Ring

摘要:

用烯丙基聚氧乙烯醚（APE）、丙烯酸（AA）、甲基丙烯磺酸钠（SMAS）和阿魏酸（FA）作为反应单体，在过硫酸铵（APS）引发下通过水溶液自由基共聚反应制备了一种新型含苯环聚羧酸系减水剂（FPC）。当n（APE）: n（AA）: n（SMAS）: n（FA）=1: 5: 0.3: 0.15时，在反应温度为85℃、反应时间为4 h、引发剂APS用量为总单体质量分数的3%时得到的FPC性能最佳。FPC的主要特点是对含泥水泥具有较强的适应性。实验结果表明，FPC的折固掺量为0.2 wt %时，含泥10 wt %的水泥净浆流动度可达308 mm，初凝时间和终凝时间分别达430和502 min，减水率可达33.2%；扫描电子显微镜（SEM）和水泥胶砂强度检测结果表明，FPC可使水泥石更加紧密均质，可以明显提高硬化水泥砂浆的抗压强度。

Abstract:

A new polycarboxylate superplasticizer (FPC) was synthesized by free radical copolymerization of crylic allyl polyoxyethylene ether (APE), acid (AA), sodium methallyl sulfonate (SMAS) and ferulic acid (FA) using ammonium persulfate (APS) as initiator. The optimum FPC was obtained when the molar ratios of APE, AA, SMAS and FA was 1: 5: 0.3: 0.15 using 3% APS by monomers total mass at 85℃ for 4 h. The remarkable feature of FPC is that it has the strong adaptability to mud cement. The application results showed that the fluidity of cement paste can reach to 308 mm, and the initial and final setting time is 430 and 502 min, respectively, and the water reducing ratio is 33.2% when FPC solid dosage is 0.2 wt% and mud content is 10 wt%. The results of SEM and compressive strength showed that FPC can make the hardened cement paste become dense and uniformity result in improving the later strength of hardened cement mortar. Key words: polycarboxylate superplasticizer; ferulic acid; microstructure; compressive strength