Branched process calibration

As pointed out by Hamielec and Ouano (8), the separation of a branched polymer by size in the SEC process results in molecular species of different molecular weights eluting at the same volume. Thus, the molecular weight of these species is not monodispersed and MCV) must be replaced by the instantaneous number average molecular weight when using the universal calibration procedure for branched polymers. 

M, M, and the MWD. It can also provide complete control of GPC systems so that large numbers of samples can be run unattended and raw data can be automatically processed. Nowadays, the software used in GPC should be capable of providing special calculations for multidetection processing, special calibration routines, polymer branching, and intrinsic viscosity determination, etc. 

Two methods of selecting and introducing the sample were devised. For small samples, 0-10 ml, a calibrated sample loop, located between the motor-operated three-way valves, was used. A branch of the process stream was continually circulated through this loop and at the... 

Most pressure sensors can be tested on-line if they are fitted widi a means of isolation from the process and branch for injecting test pressures for test calibrator. 

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