Abstract

The eco-friendly and low-cost poly(itaconic acid)/poly(sodium allyl sulfonate) (PIA/PSAS) new superabsorbent polymers (SAP) were prepared based on the monomers of itaconic acid (IA), sodium allyl sulfonate (SAS) and the cross-linking agent of N,N′-methylene bisacrylamide (MBA) by aqueous solution process. Moreover, the expanded vermiculite (EV) particles were used as reinforcement for SAP. The absorption behaviour of SAP in different liquids were studied by the teabag method, including deionized water, 0.9% NaCl solution and cement filtration. The results showed that SAP could reach the optimal liquid adsorption state under certain experimental conditions such as the molar ratio of IA/SAS as 2:1, the IA neutralization degree of 70%, the cross-linker dosage of 0.6%, and the EV content of 2.0%. The morphology and structure of the synthetic SAP were characterized. Furthermore, the effects of SAP type and content on concrete properties were evaluated. Results showed a reduction in shrinkage and revealed SAP particles acted as miniature reservoirs lead to cure concrete internally by supplying water during hydration. The EV particles reinforced SAP composite slightly and alleviated the negative influence on the compressive strength of concrete relative to PIA/PSAS. This designed SAP showed its potential to be used as an internal curing agent for concrete due to its ability to provide comprehensive protection against shrinkage and fracture.

Graphic abstract

中文翻译：

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基于聚（衣康酸）/聚（烯丙基磺酸钠）聚合物网络的新型超吸水剂，用于混凝土作为内固化剂

摘要

以衣康酸（IA）、烯丙基磺酸钠（SAS）为单体，制备了环保、低成本的聚（衣康酸）/聚（烯丙基磺酸钠）（PIA/PSAS）新型高吸水性聚合物（SAP）和N , N'的交联剂-亚甲基双丙烯酰胺 (MBA) 水溶液法。此外，膨胀蛭石 (EV) 颗粒被用作 SAP 的增强材料。采用袋泡茶法研究了SAP在不同液体中的吸收行为，包括去离子水、0.9% NaCl溶液和水泥过滤。结果表明，在IA/SAS摩尔比为2:1、IA中和度为70%、交联剂用量为0.6%、EV为一定条件下，SAP可以达到最佳液体吸附状态。含量 2.0%。表征了合成 SAP 的形态和结构。此外，还评估了 SAP 类型和含量对混凝土性能的影响。结果显示收缩减少，并显示 SAP 颗粒充当微型储层，通过在水化过程中供水，导致混凝土内部固化。EV 颗粒略微增强了 SAP 复合材料，并减轻了相对于 PIA/PSAS 对混凝土抗压强度的负面影响。这种设计的 SAP 显示出其用作混凝土内部固化剂的潜力，因为它能够提供全面的收缩和断裂保护。

图形摘要