In this study, a copolymer composed of hollow spherical particles with an average particle size of 90 µm was evaluated as a lightweight aggregate in Portland cement–fly ash mortars to improve the thermal conductivity (k) of the composite. Mortars were produced for three different water/binder ratios by mass (w/b), 0.4, 0.5, and 0.6. Optimized proportions were obtained for a minimum target compressive strength of 35 kgf/cm2 (3.4 MPa) according to the requirements of Mexican standards for nonstructural masonry units. Thermal conductivity was determined for dry and saturated samples through the transient plane technique with average results of 0.16 and 0.31 W/(m K), respectively. These values represent an increment of 23% and a reduction of 33% in comparison to an efficient Portland cement–based commercially available thermal insulator.

中文翻译：

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添加微量共聚物对粉煤灰砂浆导热系数的影响

在这项研究中，由平均粒径为 90 µm 的中空球形颗粒组成的共聚物被评估为波特兰水泥-粉煤灰砂浆中的轻质骨料，以提高复合材料的导热系数 (k)。为三种不同的水/粘合剂质量比 (w/b)、0.4、0.5 和 0.6 生产砂浆。根据墨西哥非结构砌体单元标准的要求，获得了最小目标抗压强度 35 kgf/cm2 (3.4 MPa) 的优化比例。通过瞬态平面技术测定干燥和饱和样品的热导率，平均结果分别为 0.16 和 0.31 W/(m K)。与基于高效波特兰水泥的市售绝热体相比，这些值代表了 23% 的增加和 33% 的减少。