Corn starch was used as the main raw material, and corn starch adhesive composed of sodium hydroxide, potassium pyroantimonate, borax and other accessories was added. Mainly used in cartons, corrugated board and other industries. This agent can replace the long-established alkaline scopolamine (ie, water glass) adhesive, its advantages are: simple production equipment, easy production, quick production, high adhesive strength, moisture resistance is better than silicate. Moreover, the coating amount and cost are lower than that of the buccamine adhesive.
First, formula (weight parts):
Corn starch 50 Potassium pyroantimonate 1 Borax 6.5 Solid sodium hydroxide 18
Second, the preparation method:
After corn steeped, separated, washed, ground, and dehydrated, corn starch similar to ordinary flour was prepared, which was weighed in 50 parts and made into semolina with 133 parts of water. The mixture was gelated with an aqueous sodium hydroxide solution (18 parts of sodium hydroxide dissolved in 30 parts of water), mixed at 70° C. for 30 minutes, and mixed with 300 parts of cold water, and the liquid A was uniformly stirred.
Dissolve 1 part of potassium pyroantimonate in 40 parts of water in another container, stir and dissolve, and then dilute with 1000 parts of 35°C water, and mix with 6.5 parts of borax and 500 parts of cornstarch to obtain B.
In 30 minutes, A and B were combined and stirred for 15 minutes to obtain a starch binder with excellent storage properties.
Third, note:
1. The ratio of starch to water should be suitable. Too much water will reduce the viscosity, and too little will affect the fluidity.
2. The fineness of the starch should be as fine as possible. If it is less than 99 mesh, the starch is not easily decomposed and oxidized, resulting in a product failure.
3. The amount of sodium hydroxide added is well controlled. Should not be too much, otherwise the product viscosity drops.
4. Bubbles appear during operation. The reaction mixture is mainly caused by improper proportioning of the reaction materials or the reaction time is too short. An appropriate amount of defoamer silicone oil may be added or the reaction may be resumed.
5. Sodium hydroxide is highly corrosive and can burn the skin and must be used with care.