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In this paper, a series of waterborne acrylic-modified epoxy hybrid dispersions were synthesized and successfully used as primers for coil coatings. Epoxy was phosphated to improve its adhesion to the metal substrate. The grafting reaction of acrylate monomers onto the high molecular weight epoxy resins was studied with infrared spectroscopy, differential scanning calorimetry, and nuclear magnetic resonance. The structure and resin molecules were found to be as expected and the film had the best performance when the acrylate monomer made up less than 40 wt% of the epoxy resin. Modification of the epoxy with phosphoric acid could increase the adhesion to the metal substrate. Better adhesion was achieved with greater amounts of phosphoric acid. R578 urea resin was found to be the most suitable for crosslinking of the resin in this system, and a paint film based on the resulting resin had excellent overall performance.

Abstract: The aim of conceptual design is to generate the best design candidate. Concept solving in conceptual design can be viewed as a problem of combinatorial optimization, in which there exists a “combinational explosion” phenomenon when using the traditional morphological matrix method to tackle it. In this research, a concept optimization problem is studied based on an Ant Colony System (ACS). By analyzing the similarity between concept solving and Traveling Salesman Problem (TSP), concept solving is transformed into a problem of optimal path in combinatorial optimization, where the dynamic programming based solution space model and the longest path based optimization model are developed. Then, the ant algorithm to resolve TSP is adopted to implement concept optimization according to the positive feedback searching mechanism of ACS, and some improvements are made incorporating crossover and mutation operators of a genetic algorithm (GA), to obtain the optimal scheme rapidly and effectively. Finally, a conceptual design case of press is given to demonstrate the feasibility and rationality of this proposed approach. The employment of ACS enables concept solving to be implemented with an algorithm and thus possesses better operability, which offers a promising way to solve the “combinatorial explosion” problem in conceptual design.