PA process characteristics(1)

PA is easy to absorb moisture, it must be fully dried before processing, and the water content should be controlled below 0.3%. The raw materials are dried well, the product has high gloss, otherwise it is relatively rough, PA will not gradually soften with the increase of heating temperature, but will soften in a narrow temperature range close to the melting point, the melting point is obvious, once the temperature is reached Flow occurs (unlike PS, PE, PP, etc.).

　　PA's viscosity is much lower than other thermoplastics, and its melting temperature range is narrow (only about 5 ℃). PA has good fluidity, it is easy to fill and mold, and it is also easy to walk away.

　　PA has a high melting point and a high solidification point. The melt will solidify at any time in the mold due to the temperature falling below the melting point, preventing the completion of filling molding. Therefore, high-speed injection must be used (especially for thin-walled or long-process parts). Nylon molds must have adequate exhaust measures.

　　PA in the molten state has poor thermal stability and is easily degraded. The temperature of the barrel should not exceed 300℃, and the heating time of the melt in the barrel should not exceed 30 minutes. PA requires high mold temperature. The mold temperature can be used to control its crystallinity to obtain the desired performance.

PA material mold temperature is preferably 50-90 ℃, PA1010 processing temperature is preferably 220-240 ℃, PA66 processing temperature is 270-290 ℃. PA products sometimes need to be "annealed" or "humidified" according to quality requirements.