Make sure that the instrument covers everything you’re interested in and how much information you want to extract from one analysis. If you want to measure properties like yield stress or creep, then you need to use a rheometer, which is quite expensive. But, if you are cost-conscious (considering you do not have access to any devices), a viscometer is the best option. In the case of glass viscometers, their accuracy is human-dependent causing it to vary considerably, sometimes higher than 20%, but with almost zero maintenance (if you don't break them). They are probably the cheapest, but taking into consideration that results are very subjective, probably it will not be the first option. Good luck!

Dear all, since it is concerned by electrospinning, knowing the MW and the range of viscosity/concentration are essential for the electrospinnability. Capillary viscometers are nowdays fully automated, the operators errors are at least significance. So, I recommand an Ubelhode viscometer. My Regards

Hi;

The choice of the rheological measurement device for the polymer solutions intended to be electrospun depends on the concentration of these solutions. It is possible to make a complete rheological study in steady state by means of a rheometer with cone-plane geometry or with coaxial cylinders in the case of low viscosities.

The kinematic viscosities of solutions can also be measured using a capillary viscometer of the Ubbelohde type. The formula used for the viscosity calculation is:

Ʋ (cSt) = T (s) × C (cSt/s)

With Ʋ: the kinematic viscosity (cST)

T: the flow time of the fluid (s)

C: the constant of the capillary viscometer (cSt/s)

The size of the viscometer is chosen according to the concentration of the solutions. For low concentrations, a viscometer of small size should be used. However, for high concentrations, a viscometer of larger size should be chosen.

With my best regards