Choose precise temperature control equipment: When synthesizing phenolic resin, a high-precision reactor is essential. For example, a glass-lined reactor with an intelligent temperature control system can accurately control the temperature. Through the PID control algorithm, the flow of heating or cooling medium is automatically adjusted according to the difference between the set temperature and the real-time feedback temperature to ensure the stability of the reaction environment temperature and provide a basic guarantee for product quality.
Reasonable planning of heating and cooling curves: The synthesis of phenolic resin at different stages has different temperature requirements. In the initial reaction stage, it is usually necessary to increase the temperature slowly, such as increasing at a rate of 10-15℃ per hour, to promote the uniform mixing and initial reaction of phenolic and aldehyde substances. In the polycondensation stage, it is necessary to accurately control the temperature at an appropriate temperature, generally at 100-150℃. After a period of reaction, the temperature is reasonably reduced according to the characteristics of the product to ensure the stability of the molecular chain structure and avoid the degradation of product performance due to improper temperature changes.
Real-time temperature monitoring: Install a reliable temperature sensor to monitor the temperature in the reactor in real time. The sensor should have high sensitivity and fast response capabilities to transmit data to the control system in real time. Operators can grasp the reaction progress at any time. Once the temperature deviates, they can quickly adjust to ensure that the reaction is always carried out within the set temperature range and ensure the consistency of product quality.
Adjust the time according to the reaction process: The reaction time is closely related to the temperature. For example, in the stage of forming prepolymers, if the temperature is slightly high, the reaction time can be appropriately shortened to prevent overreaction. In the curing stage, it is necessary to ensure sufficient reaction time to allow the resin to fully cross-link and improve hardness and stability. According to the characteristics of the products at different stages, such as viscosity changes, infrared spectral characteristics, etc., accurately judge the reaction process and adjust the reaction time in time.
Control the heat transfer of the reaction system: In addition to the temperature control of the reactor itself, the heat transfer of the reaction system also needs to be paid attention to. The stirring speed will affect the heat distribution. Reasonably adjust the stirring speed to make the heat transfer uniform and avoid local overheating or overcooling. At the same time, optimize the insulation layer of the reactor to reduce heat loss, stabilize the reaction temperature, and ensure product quality.
Regularly calibrate the temperature control system: To ensure the accuracy of temperature control, calibrate the temperature control system regularly. A standard thermometer can be used to measure and compare the temperature in the reactor to check the accuracy of the sensor and control system. If deviations are found, adjust the calibration parameters in time to ensure the reliability of temperature control during the entire synthesis process.
Establish a complete operating specification: formulate a detailed operating manual to clarify the control parameters of temperature and time at different stages. Operators strictly follow the specifications, confirm the equipment status before each synthesis, closely monitor the temperature and time during the process, and record the data. Through perfect specifications and strict implementation, ensure that the temperature and time control of each batch of phenolic resin synthesis is consistent, thereby optimizing product quality.
