吸水树脂复配铁氧体对煤矿封孔水泥早强性能的影响

Study on the Effect of Water-absorbing Resin SAP Compound Ferride on the Early Strength Performance of Sealing Cement in Coal Mine

针对煤矿用封孔水泥在井下复杂的工作环境中存在的早期强度不佳、凝结时间不稳定、封孔后期失效等问题,在水泥中引入高分子吸水树脂(SAP),同时复配亚纳米级镍锌铁氧体,通过抗压强度、流动度、凝结时间、XRD、电镜扫描(SEM)、热重(TG-DSC)等分析测试,研究SAP复配镍锌铁氧体对矿用水泥基封孔材料早强性能的影响。试验结果表明,当添加质量分数为0.3%SAP和1%镍锌铁氧体时,二者间产生较好的协同作用,对水泥试样早强效果的提升最为显著,其1,3,7,28 d的抗压强度分别达到了9.31,24.63,30.59,42.82 MPa,较空白组分别提升了39.58%、29.56%、26.77%、29.68%,且凝结时间明显缩短。根据微观结构分析,亚纳米材料镍锌铁氧体在水化初期因SAP粒子电离作用可形成一种紧密的高能粒子结构,使水泥内部更加致密,铝酸三钙、硅酸三钙等物质转换成氢氧化钙的速度加快,SAP和镍锌铁氧体的复配有效提高了试样早期强度和自养护性能。

Sealing cement in the complex working environment of coal mine exists the problems of poor early strength,unstable condensation time and late failure of sealing holes.In view of the problems,polymer absorbent resin(SAP)was introduced into the cement,and sub-nanometer nickel zinc ferrite was matched.Through the analysis and tests of compressive strength,fluidity,setting time,XRD,SEM and TG-DSC,the effect of sap compound nickel zinc ferried on the early strength performance of cement-based sealing materials was studied.The experimental results show that when the mass fraction of 0.3%SAP and 1%nickel-zinc ferride are added,there is a good synergistic effect between them,and the early strength of cement sample improves mostly.The compressive strength at 1,3,7 and 28 d reaches 9.31,24.63,30.59 and 42.82 MPa respectively,which is 39.60%,29.56%,26.78%and 29.69%higher than the blank group,and the condensation time is significantly shortened.According to microstructure analysis,sub-nanometer nickel zinc ferrite forms a kind of tight high-energy particle structure due to particle ionization in the initial stage of hydration,which makes the cement interior more dense and accelerate the conversion of tricalcium aluminumate and tricalcium silicate to calcium hydroxide.SAP compound ferried effectively improves the early strength and self-conservation performance of the sample.