I personally believe that in construction glue, we have to control the molecular weight and ion linking of the glue by the reaction. The bigger the molecular weight, the higher the consistency; ionic - anionic, cationic, nonionic and amphoteric ; cross linking degree - line, star, cross-linked network..
Is the molecular weight the higher the better? Is the glue the denser the better? Of course not. If the denser the glue is, the better it works, then it’s very simple, add more PAM to it.
Which type of ionic glue is better? Acrylamide glue is most likely to react into anionic type. Its thickening effect is better, but it will flocculate cement. The thickening effect of non ionic is not as good as anionic, but with relatively smaller cement flocculation. The adhesive strength of linear polymer is poor. After cross-linking, it will form a network structure and the intensity is increased, but if the cross linking is excessive, the water solubility will be weakened. The glue will get white (muddy).
Therefore, we should first specify what kind of glue we need: proper molecular weight, non ionic, suitable cross linking.
With a specific goal, we can control different reaction parameters to produce the glue we want. Acrylamide is an important polymerized monomer produced by catalyzing, hydrating, concentrating and refining acrylonitrile.
There are three ways to hydrate acrylonitrile: Acrylonitrile sulfuric acid hydration, copper-catalyzed hydration of acrylonitrile and acrylonitrile enzyme catalyzed hydration .
Acrylamide is called for AM, colorless plates, tasteless, odorless, melting point 84.5, boiling point 125, soluble in water. Acrylamide is very toxic to the central nervous system and harmful to the eyes and skin. Acrylamide is prone to self- polymerization reaction when exposed to heat or light, so it should be stored in a cool place. When producing glue, it is preferable to use fresh acrylamide. The storage should less than 2 months. Otherwise, it will generate a low acrylamide polymer (show as agglomeration and poor solubility) and affect the final glue production.
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