Study on the Test Method of High Viscosity of Hydroxypropyl Methyl Cellulose

With the NDJ-1 type of rotating viscometer and American LVDV-I+ Brookfield viscometer, the test method of viscosity of hydroxypropyl methyl cellulose(HPMC)that viscosity is more than 105 mPa·s was studied, and the test of viscosity was compared. Results showed that 1#, 2#, 3# and 4# rotor of NDJ-1 type of rotating viscometer corresponding to 61#, 62#, 63# and 64# rotor of the Brookfield viscometer. The test results were consistent at the same speed for 2% HPMC solution that viscosity is less than 105 mPa·s. After the conversion coefficient that viscosity of 1% solution divided viscosity of 2% solution obtained, viscosity of 2% solution was gained with NDJ-1 type of rotating viscometer for 2% HPMC that viscosity is more than 105 mPa·s. That was relatively complicated, and could not conform to the actual application. However, the accurate viscosity was obtained with the LVDV-I+ Brookfield viscometer due to the wide test range, conforming to actual operation and application.