The effect of processing conditions on the properties of PBT raw material

During plastic processing, processing conditions have a crucial impact on the performance of the final product. Especially for PBT (polybutylene terephthalate) raw materials, reasonable processing conditions can effectively affect its crystallinity, dimensional stability, surface quality and mechanical properties.
Injection molding temperature:
Injection molding temperature is one of the important factors affecting the performance of PBT raw materials. During the injection molding process, if the temperature is too high, it will cause the PBT raw material to melt prematurely, causing defects such as unstable product size, rough surface quality and even bubbles; and if the temperature is too low, it may cause the PBT raw material to have poor fluidity and insufficient filling. , affecting the compactness and strength of the product. Therefore, choosing the appropriate injection molding temperature is crucial to obtain high-quality PBT products.
Injection pressure:
In addition to temperature, injection pressure is also one of the key factors affecting the performance of PBT raw materials. Appropriate injection molding pressure can ensure that PBT raw materials fully fill the mold and avoid defects such as voids and shrinkage cavities in the product; at the same time, injection molding pressure can also affect the compactness and surface quality of PBT products. Excessive injection pressure may cause product deformation and excessive residual stress, affecting its mechanical properties and dimensional stability.
Cooling rate:
Cooling rate is another important factor affecting the performance of PBT raw materials. Too fast a cooling rate may cause problems such as stress accumulation and incomplete crystallization inside the PBT product, affecting its strength and dimensional stability; while too slow a cooling rate may cause problems such as rough surface of the product and poor melt fluidity. Therefore, during the injection molding process, reasonable control of the cooling rate is crucial to ensure that PBT products have good crystallinity and surface quality.
Drying process:
PBT raw materials have a certain degree of water absorption. If they are not dried during processing, moisture will affect the melt fluidity and crystallinity of PBT raw materials, leading to unstable product dimensions and reduced surface quality. Therefore, PBT raw materials need to be fully dried before injection molding to ensure its processing performance and product quality.