水泥基材料中高吸水树脂吸水行为的敏感性研究OA

This study systematically compared the water absorption behavior in cementitious materials environments of two superabsorbent polymers(SAP):sodium polyacrylate superabsorbent polymer(AA-SAP)and polyacrylamide superabsorbent polymer(AM-SAP).The effects of cementitious material type,polycarboxylate ether(PCE)dosage,stirring rate,ambient temperature,and external pressure were investigated.Results show that AA-SAP,due to electrostatic repulsion from its ionic structure,absorbs water significantly faster than AM-SAP,which relies on hydrogen bonding.In pore solutions of different cementitious materials,geopolymer systems most strongly suppress SAP swelling because of their high ionic strength.The water absorption capacity of AA-SAP has an optimal response range to PCE dosage,while the water absorption capacity of AM-SAP continuously decreases with increasing PCE content.Higher stirring rates,leveraging the Bernoulli effect,promote swelling,with a more pronounced response in AA-SAP.Elevated temperature enhances the swelling of the two types of SAPs and thus improves water absorption capacity,while external pressure suppresses the network expansion of the two types of SAPs,leading to a reduction in water absorption ratio.The absorption behavior of SAP is governed by both molecular structure and external environment:AA-SAP performs better under low ionic strength,low-to-medium shear,or warmer conditions,while AM-SAP shows greater stability in high ionic strength or high-pressure settings.The findings provide both theoretical insights and practical guidance for the application of different types of SAPs in concrete.