The glass transition temperature refers to the temperature corresponding to the polymer chain segment from freezing to thawing, activity to freezing transition point, below the glass transition temperature, the polymer is in a glassy state, the molecular chain and chain segment can not move, and only a very small deformation will occur under the action of external forces, at this time the polymer material shows obvious brittleness, when there is an external impact, The material itself cannot absorb the energy consumed, resulting in destruction; When the ambient temperature is higher than the glass transition temperature, the molecular chain segment has the ability to move, showing high elastic properties, and the external energy impact can be absorbed through the movement and deformation of the molecular chain segment, so that there is no damage, so it is obvious that the PP material blister tray is because the ambient temperature is lower than the glass transition temperature.
According to the instrument test, the glass transition temperature of PP is about 0 degrees Celsius, while the ambient temperature in northern cities in winter is generally lower than the glass transition temperature of PP, and the ambient temperature is lower than the glass transition temperature, so the activity ability of the molecular chain of PP plastic tray will decrease, and the toughness will decrease. It will easily show a very brittle crack, so in order to improve its brittleness, it is necessary to add more toughening agents in the production of PP blister trays.
