When it comes to the production of cartridges, no one will want to have the relevant matters needing attention. In fact, there are many matters needing attention in the production of cartridges, because the toughness and transparency of Finished cartridges are determined in the production process. In the process of cartridge production, we often encounter the problem of foaming and closure. What is the problem? How to solve it?
The closure of foam is due to the large elasticity of the bubble membrane wall during the foaming process, which causes the volume expansion of the gas, and the bubbles expand at the same time, but do not break down. At this time, most of the bubbles are closed. Therefore, when the foam is cooled, the gas pressure in the bubble will decrease, resulting in the shrinkage and deformation of the foam. Next, we will introduce the way to solve the foaming closed hole in the transparent plastic box.
1. The pore size and porosity of transparent cartridge can be controlled by adjusting the amount of catalyst. In the general foaming process, the amine catalyst is used to catalyze the reaction between isocyanate and water, that is to say, the foaming reaction, while the triethylenediamine or organotin catalyst is used to catalyze the reaction between isocyanate and polyols. It is gel reaction. If the catalyst is excessive, it will easily form obturator. Therefore, the solution is to reduce the dosage of gel catalyst and reduce the obturator rate.
2. Because of the close-cell formation, the degree of polymerization and branching of polyether polyols are related to the closed-cell formation of transparent cartridges. In the reaction process, polyethers with high functionality form a network structure faster and increase the closed-cell ratio. Therefore, the closed-cell ratio of transparent cartridges can be reduced by reducing the average functionality of polyethers.
3. High use of stabilizer in transparent cartridge can also lead to excessive stability of the cell, no opening, or even shrinkage, so its dosage must be appropriate. The last point is to control the index of isocyanate, because the index is too high, which will aggravate the phenomenon of closure in the morning, thus causing shrinkage.