Preparation method for furan nitrogen-free environment protection casting resin adhesive

Abstract

The invention relates to a preparation method for a furan nitrogen-free environment protection casting resin adhesive. The preparation method is characterized by comprising the specific steps: matching raw materials according to a certain mass part ratio, wherein the raw materials comprise, by mass, 60 parts of furfuryl alcohol, 30-35 parts of polyvinyl alcohol, and 15-20 parts of butyraldehyde; adding the raw materials to a reaction kettle; stirring while adding 15-20 parts by mass of furan resin acid waste water with a concentration of 12% to the reaction kettle, wherein the furan resin acid waste water is adopted as a catalyst; opening a heat source, controlling a temperature to 38-42 DEG C, and carrying out a reaction to generate an alcohol prepolymerization product; further heating to a temperature of 48-52 DEG C, and adding 60-70 parts by mass of furfuryl alcohol to the reaction kettle; closing the heat source, adjusting the PH value to a neutral PH value, adding a coupling agent when the temperature in the reaction kettle is close to 19-21 DEG C, and stirring; and filtering after 1-2 hours to obtain the product. The resin prepared by using the preparation method provided by the present invention has characteristics of good high temperature performance, high strength, low gas evolution, smooth casting surface, and energy source and heat energy saving, wherein solar energy hot water is adopted to heat, such that 100% energy source is saved.

Description

technical field [0001] The invention belongs to the technical field of chemical materials, and relates to a casting resin adhesive, in particular to a preparation method of a furan-based nitrogen-free environmental casting resin adhesive, which can be widely used in various materials, different types and different structures. Castings, especially cast iron, cast steel and non-cast alloys. Background technique [0002] Furan resin is used as binder to make sand mold and core sand. This molding process is called furan resin sand process. The furan resin sand process is solidified by the reaction of furan resin with a catalyst. Compared with traditional clay sand, oil sand and water glass sand, it has the following advantages. [0003] (1) Furan resin sand has good formability, clear contours of sand molds and sand cores, high thermal strength, and high dimensional accuracy of castings, which can save metal and save machining hours. [0004] (2) The more important thing is th...

AI Technical Summary

Problems solved by technology

But present furan resin also has many deficiencies: (1) the mold sand that nitrogen-containing furan resin is made is high in strength when the initial stage temperature of casting is low, (2) nitrogen-containing furan resin usually has higher viscosity, resulting in The surface film of the sand is thickened, and it is not suitable for mechanical automatic sand mixing

(3) Changes in the nitrogen content of the composition will change its heat resistance and strength, and at the same time, the amount of gas generated will also increase. The decomposed nitrogen will cause defects in the pores of the casting and the surface of the casting. (4) Furan resin is usually in the form of It is formed by the reaction of formaldehyde, urea and furfuryl alcohol. The free formaldehyde content in the product is high, and it is released during casting, causing environmental pollution and endangering the health of operators.

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