Characterization of branching and gelation

Below the gel point, the system is self-similar on length scales smaller than the correlation length with a power law distribution of molar masses with Fisher exponent r = 5/2 [Eq. (6.78)]. Each branched molecule is a self-similar fractal with fractal dimension 27 = 4 for ideal branched mole-cules in the mean-field theory. The lower limit of this critical behaviour is the average distance between branch points (= ). There are very few 

Above the gel point there is a macroscopic molecule (the gel). The structure of the gel is also self-similar (fractal) in the same range of length scales between the average distance between crosslinks (the linear chain size) and the correlation length  

The correlation length is the average distance between branch points that are connected to several branches leading to infinity (the boundary of the gel). At/ Ri 2pc (al 1) the gelation regime ends and most of the network 

Refractive index (line) and 15° light scattering (points) detector outputs as functions of elution volume for size exclusion chromatography on a randomly branched polyester sample dissolved in tetrahydrofiiran. Data from 

Knowledge of the concentration c, and weight-average molar mass of each elution volume enables calculation of the weight-average and z-average molar masses  

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