Thermo Scientific HAAKE CaBER 1 extensional rheometer is able to detect slight differences in the MWD (molecular weight distribution) of blended polystyrene standards.
However, the question remains if these results obtained on a standard system can be transferred to more complex polymers in solution like cellulosic derivatives?
In order to control the adaptability of this method, commercially available, blended methylhydroxy ethyl celluloses (MHEC, e.g. used as thickener agent in construction materials) were characterised by uniaxial elongation in capillary break-up experiments with the CaBER 1 extensional rheometer. The determined break-up and relaxation times t resp. τ were then correlated with the blending composition of the methylhydroxyethyl celluloses and hence with the high molar mass fraction of the sample.
A full copy of the application note is available on request by quoting V-219