Superabsorbent polymers (SAPs) are widely studied as internal curing agents in high-performance concrete, but their adverse effects on pore structure remain a challenge. This study introduces an innovative cement-integrated SAP (CiSAP) by modifying the interface, using KH570-modified cement (KMC) as the functional core. By optimizing KMC content, the microstructure was improved, leading to enhanced performance. Structural characterization confirmed that KMC was successfully embedded into the polymer network. CiSAP30 reduced shrinkage by 61.4 % due to its excellent desorption efficiency. The 28-day strength retention of CiSAP in cement-based materials varied from 93.4 % to 99.6 %, compared to the reference group without CiSAP. MIP and fractal dimension analysis indicated that CiSAP refined the microstructure by reducing large capillary pores and filling macropores. The sustained water release from CiSAP, along with KMC hydration, promoted long-term densification and controlled autogenous shrinkage. This study provides a novel strategy for designing internal curing agents for high-performance cement-based materials.

中文翻译：

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内部固化剂的微观结构定制：改性水泥颗粒/高吸水性聚合物复合材料平衡强度和收缩缓解

高吸水性聚合物 （SAP） 作为高性能混凝土中的内部固化剂被广泛研究，但它们对孔隙结构的不利影响仍然是一个挑战。本研究通过修改界面，以 KH570 改性水泥 （KMC） 为功能核心，引入了一种创新的水泥集成 SAP （CiSAP）。通过优化 KMC 含量，微观结构得到改善，从而提高了性能。结构表征证实 KMC 已成功嵌入聚合物网络。CiSAP30 具有出色的解吸效率，可将收缩率降低 61.4%。与不含 CiSAP 的参考组相比，CiSAP 在水泥基材料中的 28 天强度保持率从 93.4 % 到 99.6 % 不等。MIP 和分形维数分析表明，CiSAP 通过减少大毛细孔和填充大孔来细化微观结构。CiSAP 的持续水分释放以及 KMC 水化促进了长期致密化并控制了自体收缩。本研究为设计高性能水泥基材料的内部固化剂提供了一种新的策略。