The Synthesis Technology And Application Research On Coal-Phenolic Resin For Foundry

The paper focused on improving the environmental influence of phenolic resin for foundry as well as investigating new raw materials in order to reduce material cost. The partial phenol was replaced by nitryl-coal to prepare the coal-phenolic resin.After oxidized by the nitric acid the surface of lignite particle can produce the functional group structure which can attend the synthetic reaction. In the paper, some key factors were discussed. The paper studied the main factors by single factor experiments, such as reaction temperature, reaction time, the ratio of coal and acid and the concentration of the nitric acid. Consequently the optimum yield rate of acetone soluble was obtained. In theory it was analyzed that the nitric acid oxidation reaction on lignite was a complicated chain reaction, and confirmed that the nitryl-coal and the acetone soluble had the needed functional groups by FTIR and could be the monomers of the phenolic resin of the synthetic reaction.Based on the nitryl-coal preparation, the single factor experiments studied the effects of main factors on the reaction, such as the ratio of the phenol and formaldehyde, reaction time, catalyst contents, the means of adding catalyst, the quantity of adding the nitryl-coal and reaction temperature. In theory it was analyzed that the synthetic process of the coal-phenolic resin had two steps: addition reaction on the low temperature, and phenol hydroxyl groups and liveliness hydrogen polycondensation reaction on high temperature. Theoretically the resin structure was analyzed and characterized by FTIR. Based on these, the heat solidification temperature and time on the coal-phenolic resin were obtained, and the solidification process of the resin was characterized by DSC and the solidification mechanism was analyzed.Based on the coal-phenolic resin preparation, the technique of phenolic resin modified by melamine and furfural and crylic acid is elementarily discussed, the reaction mechanism and solidification mechanism were discussed. The waterproof performance of the modified coal-phenolic resin by melamine was studied.