In my dissertation, I studied the effect of controlled lowering and raising of the pH value on the encapsulation of three different core materials by three different procedures. I chose guaiacol-furfuryl benzoxazine, 4,4'-Bismaleimidodiphenylmethane and N-Phenylmaleimide as the solid core material. Process parameters such as temperature and mixing speed were identical in all encapsulations. The encapsulation process began the same for all three procedures. The content of the mixture in the reactor was adjusted to pH 8 before encapsulation, and then the pH of the reaction mixture was adjusted according to the procedure. By differential dynamic calorimetry and electron microscopy, I found that only in the case of the use of 4,4'-Bismaleimidodiphenylmethane as a core material the encapsulation was successfull and complete. I also found that with a multiple increase and subsequent decrease in pH from 6 to 8, the wall of the microcapsules improves or becomes thicker.
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