In understanding the temperature of the blow molding ma […]
In understanding the temperature of the blow molding machine, let's first look at a few definitions, and through these definitions, let's analyze the meaning of the inactive temperature.
First: Glass transition temperature TG: refers to the transition temperature of the amorphous polymer (including the non-crystalline part of the crystalline polymer) from the glass state to the highly elastic state or from the latter to the former. It is the lowest temperature for the free movement of the macromolecular segment of the amorphous polymer and the upper limit of the working temperature of the product.
Second: Melting temperature TM: With regard to crystalline polymers, it refers to the temperature at which the three-dimensional remote ordered state of the macromolecular chain structure changes into disordered viscous flow state, also known as melting point. It is the lower limit of the molding temperature of crystalline polymers.
Third: Differentiation temperature TD: When the temperature of the polymer in the viscous flow state is further increased, the degradation of the molecular chain will increase, and the temperature when the polymer molecular chain is significantly degraded is the differentiation temperature.
Fourth: Active temperature TF: refers to the temperature at which an amorphous polymer changes from a highly elastic state to a viscous state. It is the lower limit of the processing temperature of amorphous plastics.
The above are the literal meanings of the four temperatures, and the next analysis is about the correlation of the active temperature. If the material does not flow out of the die, raise the temperature of the material by 10 degrees after the pressure is relieved, and then apply a constant pressure of the same size after holding for 10 minutes. This continues until the melt flow from the die stops, reducing the temperature 10 degrees is the inactive temperature of the material. The highest temperature that does not produce activity under a certain pressure. A certain amount of plastic is added to the barrel at the upper end of the capillary rheometer die, heated to a certain temperature, constant temperature, so after 10 minutes, it is applied to a constant pressure under 50 pressure. /
