Inorganic adhesives have received increased attention due to their high temperature resistance, non-toxicity, and environment friendliness. However, poor adhesion strength of inorganic adhesives hinders their application. Further, graphene improves the mechanical and thermal properties of polymer composites. Herein, graphene nanoplatelets (GNP) with different specific surface areas were added into a mixed silicate (MS) containing different ratios of alkali silicates. The results revealed that lap shear strengths increased from 7.4 MPa with the unmodified MS to 9.42 MPa with the MS/GNP 750_10% composite. In addition, the GNP powder with the highest surface area (MS/GNP 750_10% composite) formed maximum interfaces with the silicate matrix, leading to effective load transfer and reduction in stress concentration sites. Hardness and modulus increased as the GNP surface area increased; unmodified MS had the highest values because GNP changed MS from brittle to ductile. In addition, at room temperature, thermal conductivity increased by 60% in the vertical direction and 173% in the horizontal direction in the MS/GNP 750_10% composite compared to the unmodified MS. Furthermore, at a higher temperature (100 °C), the thermal conductivity of the MS/GNP 750_10% composite increased by 273% in the vertical direction and 412% in the horizontal direction.

无机胶粘剂因其耐高温、无毒、环保等优点而受到越来越多的关注。然而，无机粘合剂较差的粘合强度阻碍了它们的应用。此外，石墨烯改善了聚合物复合材料的机械和热性能。在此，将具有不同比表面积的石墨烯纳米片（GNP）添加到含有不同比例的碱金属硅酸盐的混合硅酸盐（MS）中。结果表明，搭接剪切强度从未改性 MS 的 7.4 MPa 增加到 MS/GNP 750_10% 复合材料的 9.42 MPa。此外，表面积最大的 GNP 粉末（MS/GNP 750_10% 复合材料）与硅酸盐基体形成最大的界面，导致有效的载荷转移和应力集中部位的减少。硬度和模量随着 GNP 表面积的增加而增加；未修改的 MS 具有最高值，因为 GNP 将 MS 从脆性变为韧性。此外，在室温下，与未改性的 MS 相比，MS/GNP 750_10% 复合材料在垂直方向上的热导率增加了 60%，在水平方向上增加了 173%。此外，在更高的温度（100°C）下，MS/GNP 750_10% 复合材料的热导率在垂直方向上增加了 273%，在水平方向上增加了 412%。