褐土色低红外发射率涂层的制备及性能研究

Preparation and performance study of low infrared emissivity coatingwith brown earth color

以环氧树脂为黏合剂,片状Cu粉为功能颜料,石墨烯和邻苯二甲酸二辛酯(DOP)为界面结构改性剂,制备得到了一种具有良好综合性能的褐土色低红外发射率涂层。系统研究了片状Cu粉添加量(质量分数)、石墨烯添加量(质量分数)及DOP添加量(质量分数)对涂层微结构、发射率、光泽度及力学性能的影响规律。结果表明:合适的片状Cu粉添加量可以构建出表面结构规整、颜料分散均匀、片状Cu粉定向与涂层表面平行的微观结构,从而使涂层实现较低的发射率性能。石墨烯改性可提高涂层的致密度,减少由树脂填充的空隙,从而可进一步降低涂层的发射率。黑色石墨烯改性可明显强化涂层对可见光的吸收作用,从而降低涂层的光泽度。另外,利用石墨烯固有的高强度及高韧性特点,可改善涂层的柔韧性和耐冲击强度。DOP可通过减弱环氧树脂分子间作用力和增强分子链的移动性来提高涂层的塑性和韧性,从而可明显改善涂层的柔韧性和耐冲击强度。当涂层中片状Cu粉、石墨烯和DOP的添加量分别为40%、8%和7%时,所制备的褐土色涂层具有最佳的发射率(0.222)、光泽度(20.4)、附着力(1级)、柔韧性(2mm)及耐冲击强度(50kg·cm)性能。

Using epoxy resin as binder,flake Cu powder as functional pigment,graphene and dioctyl phthalate(DOP)as interfacial structural modifiers,a brown earth color low infrared emissivity coating with good comprehensive properties was prepared.The effects of the addition amounts of flake Cu powder(mass fraction),graphene(mass fraction),and DOP(mass fraction)on the microstructure,emissivity,glossiness,and mechanical properties of the coating were systematically studied.The results showed that the microstructure with regular surface structure,uniform pigment dispersion,and flake Cu powder oriented parallel to the coating surface could be constructed with appropriate amount of flake Cu powder addition,thereby achieving lower emissivity.The graphene modification could increase the density of the coating and reduce the void filled by the resin,which could further reduce the emissivity of the coating.The modification of black graphene could significantly enhance the coating‘s absorption for visible light,thus reducing the glossiness of the coating.In addition,the inherent high strength and toughness of graphene could be used to improve the flexibility and impact strength of the coating.DOP could improve the plasticity and toughness of the coating by weakening the intermolecular force of the epoxy resin and enhancing the mobility of the molecular chain,so that the flexibility and impact strength of the coating could be significantly improved.When the addition amounts of flake Cu powder,graphene,and DOP in the coating were 40%,8%,and 7%,respectively,the prepared coating with brown earth color had the best emissivity(0.222),glossiness(20.4),adhesion strength(grade 1),flexibility(2mm),and impact strength(50kg·cm).