【Required Score for Participation】Regarding the adjustment of initiators~!
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Polymerization was carried out using an appropriate initiator; for the 70-cubic-meter reactor, EHP+CNP was used. Overheating occurred after 120 minutes of reaction, and overheating happened again before the reaction was completed. Is adjusting the EHP+CNP ratio in this way intended to reduce overheating?
Reduce the amount of EHP slightly. At the same time, pay attention to the changes in water volume during the middle and later stages of the reaction.
Is this phenomenon frequent or occasional? Is it related to the external temperature?
Frequently! The water temperature in our cycle is quite high. 25 degrees up
Appropriately reducing EHP increases CNP. If the heat dissipation conditions permit, the reaction can be accelerated appropriately in the early stage, whereas a high concentration of the low-activity initiator cannot be used in the middle and later stages.
We also experience this phenomenon that the poster mentioned; we call it \"tail lifting\". Later in the reaction process, it’s necessary to add some water, especially during production in summer. In such cases, we reduce the amount of initiator used, though the reaction time increases slightly
Gradually increase the amount of CNP and decrease the amount of EHP. If the reaction time is not long, the total amount can be kept constant at the start, with the proportions adjusted. After adjusting to a certain ratio, when the reaction time begins to decrease and the heat release becomes excessive, the total amount can be appropriately reduced. The maximum ratio of CNP to EHP can be 1:1. It depends on your polymerization temperature, circulating water temperature, and the heat transfer performance of the polymerization reactor.
It might be due to insufficient cooling; the amount used can be reduced appropriately
Both of these stages mentioned by the poster are peak periods of exothermic reaction; if the valves and flow rates of the jacket and internal baffles are all set to their maximum values, it should be considered to reduce the amount of initiator added accordingly. Otherwise, simply adjusting the ratio of EHP to CNP may still lead to overheating
Agree with what was said above; the compounding ratio should be appropriate, and the amount of initiator added needs to be reduced
Adjusting the amount of initiator added, as well as the ratio of CNP to EHP, requires gradual experience accumulation. Here, we often experience excessive temperature and pressure during the summer; there’s no other option but to reduce the dry dosage of the initiator. :)