as the solvents used to dissolve them; as can be observed some of them require high temperature in order to be run by GPC. Most of the rubbers can be dissolved in toluene at 75◦C. Most of the amorphous polymers can be prepared at room temperature, but semicrystalline polymers require high temperatures to be dissolved.
Branching High temperature GPC equipment generally counts with different types of detectors such as refractive index, light scattering, and viscometer, among others; using these detectors it is possible to obtain the absolute MW, and in most cases it is not necessary to construct a calibration curve. A viscometer detector also provides information about the level of branching of a polymer; in fact, using this it is possible to obtain the index of branching (g), which is defined by the following equation [28]: