低压供热涂层材料制备及热性能研究

Preparation and Thermal Performances of Heating Coating with Low-Voltage

低压供热技术具有安全系数高和节能降耗等优势,因而成为石化稠油长输管线、风力发电叶片冬季防覆冰和室内供暖等领域的研究热点之一。本文制备了一系列低压供热涂层材料,研究不同碳功能填料对涂层发热速率、发热功率及最高发热温度的影响规律,并揭示石墨烯和碳纤维对提升涂层材料热性能的协同作用。其中石墨烯纳米片的还原程度对材料热性能具有重要影响,降低其表面官能团密度对提升涂层供热特性具有促进作用,但是官能团密度过低会导致石墨烯纳米片的团聚现象,引起涂层发热不均匀。加入适量碳纤维可以提高石墨烯的均匀分散性,提升发热速率。优化石墨烯纳米片和碳纤维的比例后,采用24V电压驱动时,涂层材料的发热速率达到7.1℃·s^(-1),功率密度为800W·m^(-2),最高发热温度为124℃。

Heating technology with low-voltage displays some superiorities including high safety and energy saving,which attracting increasing attention in the heavy oil pipeline heating,wind power generation blade anti-icing and indoor heating fields.A series heating coatings working under low-voltage were prepared,and the influences on the heating rate,heating power and maximum heating temperature from carbon materials had been revealed.Moreover,a synergetic effect between the adopted graphene nanosheets(GNS)and carbon fiber(CF)was found.The reduction degree of the GNS acts as the determining factor to the resulting thermal performances,and a lower functional group density of GNS improves thermal properties.However,an excessive low functional group density leads to the agglomeration behavior of GNS,which causing the nonuniform heating temperature.The present of CF upgrades the dispersibility of GNS in the coating as well as the heating rate.After optimizing the ratio of GNS and CF,the heating rate,heating power and maximum heating temperature reach 7.1℃·s^(-1),800 W·m^(-2) and 124℃with 24 V power supply.