What is the "TG" point of the resin?
The glass transition temperature (glass transition temperature), refers to the amorphous polymers (including non crystalline part of crystalline polymers in the glassy transition temperature) to high elastic state or by the latter on the lowest temperature of amorphous polymer chain segment free movement, usually expressed in Tg. There are no very fixed values that change with the methods and conditions of measurement. For example, the glass transition temperature of PVC is 80 degrees centigrade. But he is not the upper limit of the working temperature of the product.
The TG point of the resin refers to the glass transition temperature of the resin.
Glass transition temperature Tg is an important characteristic parameter of materials. Many properties of materials change sharply near the glass transition temperature. In the glass, the glass transition temperature, due to changes in the structure of the glass, the glass of many physical properties such as density, heat capacity, thermal expansion coefficient and conductivity in the temperature range changed sharply. According to the glass transition temperature, the heat treatment temperature system of glass can be accurately formulated. The polymer, which is from the polymer glass transition temperature for high elastic state, the glass transition temperature of polymer, heat capacity, thermal expansion coefficient, viscosity, refractive index, free volume and elastic modulus have a mutation. From the molecular structure, the glass transition temperature of polymer is amorphous part from the frozen state to a relaxation thawing state, rather than the phase transition as a phase change heat, so it is a kind of two order phase transition (dynamic mechanical polymer known as the main change). Below the glass transition temperature of polymers in the glassy state, the molecular chains or chain segments are not moving just molecules atoms (or groups) for vibration in its equilibrium position; and in the glass transition temperature of the molecular chain is not moving, but the chain segment movement, exhibit high elastic properties, temperature and then rise, makes the whole chain movement and show the properties of viscous flow.
