- 周 恒,霍冀川,雷永林
2012年第6期
摘要
引用本文
摘??要:以順丁烯二酸酐(MA),α-甲基丙烯酸(MAA),烯丙基聚氧乙烯醚-1000(APEG-1000)為單體,過硫酸銨(NH4S2O8)為引發劑,合成一種聚羧酸高性能緩凝減水劑。通過紅外光譜對減水劑分子共聚反應進行表征,掃描電鏡觀察水化物微觀結構,X射線衍射觀察對水化物的影響,進行水泥凈漿性能測定。結果表明,在水灰比0.29,減水劑摻量為水泥質量0.3%的情況下,水泥凈漿流動度達到340mm,減水率達到30.4%,具有較強的緩凝效果,初凝和終凝時間達到483min和1320min。硬化水泥漿體抗壓強度得到提高,與空白樣對比,7d和28d抗壓強度比達到了121.6%、138.2%。Abstract:Anovelretardinghighperformancepolycarboxylatewaterreducerissynthesizedwithmaleicanhydride(MA),mathacrylicacid(MAA)andallylalcoholpolyoxyethylene-1000(APEG-1000)initiatedbyammoniumpersulfate.Fouriertransforminfraredspectroscopyisusedtoindicategraftingprocess,SEMisusedtoobservemicrostructureofthehydrationofcement,XRDisusedtoobservetheinfluenceofthehydrationofcement,andtheinfluenceofpolycarboxylicsuperplasticizerontheperformanceofcementpasteisinvestigated.Theresultsshowthatwhenthesuperplasticizerdosageis0.3%ofcementmass,togetherwith0.29ofwatercementratio,thefluidityofcementpastecanreach340mm,thewater-reducingrateis30.4%,theretardingeffectisdistinct,anditsinitialsettingtimeis483minanditsfinalsettingtimeis1320min.Thecompressivestrengthofhardenedcementpasteisimproved,andthecompressivestrengthratiosof7dand28dare121.6%and138.2%comparedwithblanksamples.