引气剂起泡和稳泡能力的温度敏感性研究

Temperature Susceptibility of Foamability and Foam Stability of Air-entraining Agent

高原高寒地区混凝土施工时,低温影响引气剂作用效果。为研究不同种类引气剂作用效果的温度敏感性,本工作基于Waring-Blender法测试获得了三种不同种类引气剂溶液在0~30℃的泡沫体积,研究了引气剂分子间相互作用、表面活性参数和体相黏度随温度的变化规律。引气剂分子间相互作用力的温度敏感性因分子结构不同而有所差异。灰色关联分析显示,影响引气剂溶液起泡性的关键因素为表面张力γ、最大吸附量Γ_(max)和最小分子占据面积Amin,稳泡性受Γ_(max)、γ和体相黏度η控制。随温度降低,不同种类引气剂表面活性的温度敏感性不同,γ、Γ_(max)和η增大幅度以及Amin减小幅度均不同。引气剂起泡性和稳泡性的温度敏感性受多因素共同影响。研究结果促进了对不同引气剂作用效果温度敏感性的更深入理解。

Low temperature affects the usage of air-entraining agents(AEA)during the concrete construction in cold area.In order to study the different responses to temperature change of the foaming properties of different kinds of AEA,the foam volume,the surface activity and the bulk viscosity of three kinds of AEA were tested at the temperature between 0℃and 30℃using the method of Waring-Blender.The temperature susceptibility of intermolecular interaction force varies with different molecular structures.The grey correlation analysis results show the key factors influencing the foamability of AEA are the surface tensionγ,the saturation adsorption amountΓ_(max),the minimum molecular area Amin.As for the foam stability of AEA,the key factors areγ,Γ_(max)andη.With temperature decreases,the increasing degree of the surface tension,the_(max)imum adsorption and the viscosity,together with the decreasing degree of the minimum molecular area when the temperature changes from 30℃to 0℃varies because of the temperature susceptibility of surface activity.The temperature susceptibility of foaming capacity and stability of AEA are affected by various factors.The research is expected to provide an in-depth understanding of the temperature sensitivity of different AEAs.