不同分散剂对硅溶胶结合刚玉质浇注料流动性、凝结时间和脱模强度的影响

发布时间：2018-08-26 09:24

【摘要】：由于硅溶胶ζ-电位较高导致硅溶胶结合浇注料具有较高的稳定性,因此在浇注后很长时间内都不能凝结硬化,脱模强度较低,从而不能得到广泛应用。所以,要想改善硅溶胶结合浇注料的施工性和使用性,就必须解决其凝结时间长和脱模强度低的问题,合适的外加剂的添加就显得很有必要。本文考察了分散剂的类型和加入量与硅溶胶结合浇注料的流动性、凝结行为之间的关系,并弄清分散剂对硅溶胶结合浇注料不同时间的流动性影响的实质。实验选取了六种不同类型的分散剂,六偏磷酸钠、三聚磷酸钠、柠檬酸、FS10、FS20和聚乙二醇(PEG400),研究硅溶胶ζ-电位、粘度,混合浆体(硅溶胶+CL370)粘度、基质浆体(硅溶胶+CL370微粉+刚玉细粉325目)粘度和浇注料流动性、脱模强度随分散剂种类、加入量和时间的变化,考察ζ-电位和粘度与流动性的内在联系。通过测量加入不同分散剂种类和加入量后浇注料养护不同时间的流动性变化来研究浇注料的凝结行为。通过测量浇注料加入分散剂养护24h后的抗折和耐压强度,分析分散剂对浇注料脱模强度的影响。用Zeta电位仪和流变仪分别(1)测量了加入上述六种不同类型不同比例(%,0、0.01、0.03、0.05、0.1、0.15、0.2、0.3)的分散剂并放置不同时间(0min、15min、30min、45min、60min、90min、120min)的硅溶胶ζ-电位(只用了SHP、STP、柠檬酸)和表观粘度。着重分析了不同外加剂的结构、尺寸大小及其加入量对硅溶胶稳定性(ζ-电位)和粘度的影响机理。(2)分别研究了分散剂种类和加入量(%,0、0.1、0.5、1、2、3、4,相对于浆体中固相含量而言)对固含量为30wt%的CL370浆体和刚玉细粉325目浆体粘度的影响。(3)研究了分散剂对混合浆体(固含量60wt%)表观粘度的影响,实质上也是研究CL370微粉的加入对硅溶胶表观粘度随分散剂加入量和放置时间的变化曲线的影响。分散剂加入量由硅溶胶粘度随分散剂的变化结果来确定。(4)研究了分散剂对基质浆体(固含量60wt%)表观粘度的影响,实质上也是研究325目刚玉细粉的加入对硅溶胶和CL370混合浆体表观粘度随分散剂加入量和放置时间变化曲线的影响。分散剂比例选取同混合浆体中的一致。(5)研究了分散剂种类和加入量(同混合浆体中所加分散剂比例一致)对浇注料流动性的影响。分析加入分散剂后,硅溶胶ζ-电位和表观粘度、混合浆体表观粘度、基质浆体表观粘度的变化与浇注料流动性之间的关系。(6)研究了分散剂种类和加入量(同混合浆体和基质浆体中加入的分散剂比例一致)对养护24h后的浇注料脱模强度的影响。分析分散剂是否能提高浇注料的脱模强度。并找出使浇注料能同时满足施工的流动性要求和脱模强度要求的分散剂种类和加入量。结果表明,合适的分散剂加入量可以降低硅溶胶、混合浆体和基质浆体的粘度;提高浇注料的流动性和脱模强度。浇注料流动性好坏和经时损失大小与硅溶胶粘度的变化有关,粘度越低,浇注料流动性越好,前提是硅溶胶│ζ│≥30m V。分散剂加入量在一定时,若硅溶胶粘度随时间增加较快,那么浇注料流动性就会衰减很快。
[Abstract]:Because the high_-potential of silica sol leads to the high stability of silica sol bonded castables, it can not harden for a long time after pouring, and the demoulding strength is low, so it can not be widely used. In this paper, the relationship between the type and amount of dispersant and the fluidity and solidification behavior of silica sol bonded castables was investigated, and the effect of dispersant on the fluidity of silica sol bonded castables at different time was clarified. Type I dispersants, sodium hexametaphosphate, sodium tripolyphosphate, citric acid, FS10, FS20 and polyethylene glycol (PEG400), silica sol_-potential, viscosity, mixed paste (silica sol + CL370) viscosity, matrix paste (silica sol + CL370 powder + corundum powder 32mesh) viscosity and castable fluidity, demoulding strength with the type of dispersant, dosage and time changes _-potential, viscosity and fluidity were investigated. The solidification behavior of castables was studied by measuring the fluidity of castables cured at different time after adding different dispersants. The bending and compressive strength of castables cured with dispersants for 24 hours were measured, and the release strength of dispersants was analyzed. Zeta potentiometer and rheometer were used to measure the_-potential (SHP, STP, citric acid only) and apparent viscosity of silica sol with different proportions (%, 0, 0.01, 0.03, 0.05, 0.1, 0.15, 0.2, 0.3) and different time (0 min, 15 min, 30 min, 45 min, 60 min, 90 min, 120 min). The effects of additives on the stability (_-potential) and viscosity of silica sol were studied. (2) The effects of dispersants and additives (%, 0,0.1,0.5,1,2,3,4, relative to the solid content in the slurry) on the viscosity of CL370 slurry and corundum powder 325 mesh slurry with solid content of 30 wt% were studied. (3) The content of dispersants was studied. The effect of dispersant on the apparent viscosity of the mixed slurry (solid content 60wt%) is essentially to study the influence of the addition of CL370 powder on the curve of apparent viscosity of silica sol with the addition of dispersant and the time of storage. The amount of dispersant is determined by the change of viscosity of silica sol with dispersant. (4) The effect of dispersant on the matrix slurry (solid content) is studied. The effect of the content of 60wt% on the apparent viscosity of 325 mesh corundum powder was also studied. The effect of the addition of 325 mesh corundum powder on the apparent viscosity curve of silica sol and CL370 mixed paste was also studied. The influence of dispersant proportion on the fluidity of castables was studied. The relationships between the_-potential and apparent viscosity of silica sol, the apparent viscosity of mixed paste, the apparent viscosity of matrix paste and the fluidity of castables were analyzed after adding dispersant. (6) The types and dosages of dispersants (with dispersants added to mixed paste and matrix paste) were studied. The effect of dispersant on the demoulding strength of castable cured for 24 hours was analyzed. The types and amount of dispersant were found to meet the requirements of both construction fluidity and demoulding strength. The results showed that the appropriate amount of dispersant could reduce the silica sol and mix. The viscosity of the slurry and matrix slurry is related to the change of the viscosity of silica sol. The lower the viscosity, the better the fluidity of the castable. The premise is that the addition of silica sol_ > 30mV. If the viscosity of silica sol increases rapidly with time at a certain amount of dispersant. Then castability will decay rapidly.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ175.732

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