To shed light on the self-stratification mechanism in epoxy–acrylic coatings, 200-, 400-, and 800-micron-thick coatings were applied on glass and aluminum substrates, and their solidification behavior was studied. Some of the applied coats showed self-stratification behavior, with the thermoplastic acrylic copolymer in the top layer. In addition, experiments were performed on epoxy–acrylic solutions without hardeners to evaluate the resulting convective patterns on the solution surface, which exhibited finger-type convection. The final structure of the films had an apparent dependency on the thickness. Thicker films were usually more stratified and had a thicker stratified layer. As these observations could not support diffusion as the primary mechanism of self-stratification, convection experiments were done on epoxy and coatings solutions. The surface patterns on the solutions were studied, and the finger-type convection was observed. Based on these observations, we propose that convection may be the primary movement mechanism rather the diffusion of polymers toward the surface in the self-stratifying coats.

为了阐明环氧丙烯酸涂料的自层化机理，在玻璃和铝基材上施涂了200、400和800微米厚的涂料，并研究了它们的固化行为。一些涂覆的涂层表现出自分层行为，热塑性丙烯酸共聚物位于顶层。此外，在没有固化剂的环氧丙烯酸溶液上进行了实验，以评估在溶液表面上表现出的对流模式，该模式表现出手指型对流。膜的最终结构明显取决于厚度。较厚的膜通常更分层并且具有较厚的分层层。由于这些观察不能支持扩散作为自分层的主要机理，因此在环氧和涂料溶液上进行了对流实验。研究溶液的表面图案，并观察到手指型对流。基于这些观察，我们提出对流可能是主要的运动机制，而不是聚合物在自分层涂层中向表面的扩散。