The more elevated the temperature, the more readily the material flows, which results in a lower measured viscosity compared to ambient or sub-ambient conditions. With all viscosity techniques, temperature can greatly impact the results of testing. Common test methods for kinematic viscosity include ASTM D4212, ASTM D1200 and ASTM D445. Intrinsic viscosity is normally performed using the Ubbelohde viscometer.ĭepending on the equipment used, kinematic viscosity can be reported in units of meters squared per second, stokes, centistokes or time in seconds. Intrinsic viscosity is an important technique for characterizing polymers in dilute solution, because it provides information related to molecular weight and the conformational shape of a specific polymer in a chosen solvent.
Therefore, the typical applications for capillary viscometers include: dilute polymer solutions, certain types of solvents, dilute solutions, syrups and oils. The capillary geometry is too small for highly viscous samples. The Ubbelohde and Cannon-Fenske viscometers utilize a glass capillary through which the fluid flows under gravity. The cup-type viscometers are typically used for paints, inks, varnishes and highly viscous coatings. Common ASTM test methods for dynamic viscosity include ASTM D4287, ASTM D562 and ASTM D2196.ĮAG Laboratories performs kinematic viscosity measurements using the following viscometers: Depending on the equipment used, viscosity data can be reported in units of centipoise, poise, Pascal-seconds or Krebs units. The instruments contain a calibrated spring that measures the fluid’s resistance to the movement. Rotational viscometers of various torque ranges manufactured by Brookfield Engineering Corp.įor all of these instrument types, a cone, spindle or paddle is placed in contact with the test fluid and is rotated at a programmed shear rate.Krebs spindle viscometer (KU meter) for paints, pigmented coatings, pastes and adhesives.High shear rate viscometer for paints and pigmented coatings, also known as an ICI viscometer.
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