作者：苏东仓
作者单位：青岛兴业商砼有限公司，山东 青岛 266112
关键词：高性能吸水树脂;净浆;力学性能;水泥水化;耐久性;电阻率
摘要：
高性能吸水树脂（super-absorbent polymers，SAP）作为一种新型高分子材料由于其高保水性，可作为水泥基材料理想的内养护材料，促进水泥水化，降低水泥材料的早期收缩。该文研究不同SAP的吸附脱附原理，以及其对净浆的力学性能，水化程度，耐久性和导电性能的影响规律。结果表明，SAP可提高净浆早期抗压强度，2 kg/m3为力学实验的最优掺量；净浆电阻率在掺有SAP后有下降趋势；SAP掺入后混凝土抗渗性在一定程度上降低；且SAP粒径大小和吸附脱附速率对净浆的电阻率影响较大，通过扫描电镜观察到SAP特有的微观封闭球状孔结构。
The multiple properties of cement materials modified with super-absorbent polymers
SU Dongcang
Qingdao Xingye Concretes Co., Ltd., Qingdao 266112, China
Abstract: Super-absorbent polymers (SAP) is a novel polymeric material because of its high water retention and can be used as the internal curing materials in cement-based composites which can promote the hydration of cement and reduce the early shrinkage of concrete. This paper investigates the influence of different SAP on mechanical properties and electrical conductivity of the paste. The results show that SAP can increase the early age strength of the paste, but the compressive strength is weakened in the later stage. Moreover, 2 kg/m3 is the optimal dosage for the cement paste in mechanical experiments. The particle size of SAP and the rate of adsorption and desorption have a large effect on the resistivity of paste. The resistivity of cement paste has a downward trend after being doped with SAP. The closed spherical pore structure of SAP was observed by scanning electron microscope.
Keywords: super-absorbent polymers;cement paste;mechanical properties;cement hydration;durability;electric conductivity
2021, 47(6):109-117 收稿日期: 2020-11-30;收到修改稿日期: 2021-01-13
基金项目: 山东省自然科学基金(ZR2016EL06)
作者简介: 苏东仓(1987-),男,山东济宁市人,工程师,研究方向为新型建筑材料
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