ASTM D3236 Standard Test Method for Apparent Viscosity of Hot Melt Adhesives and Coating Materials
6. Apparatus
6.1 Viscometer, Concentric Cylinder Rotational - The essential instrumentation required providing the minimum rational viscometer analytical capabilities include:
6.1.1 Drive motor, to apply a unidirectional rotational displacement to the specimen at a rate of 0.5 r/min to 60 r/min constant to +/- 1 %.
6.1.2 Force sensor, to measure the torque developed by the specimen in response to the rotational displacement.
6.1.3 Coupling shaft, or other means to transmit the rotational displacement from the motor to the specimen.
NOTE 4 - It is helpful to have a mark on the shaft to indicate appropriate test fluid level.
6.1.4 Stainless steel rotational element, spindle, or tool, for the type shown in Fig. 1 to fix the specimen between the draft shaft and a stationary position.
6.1.5 Data collection device, to provide a means of acquiring, storing, and displaying measured or calculated signals, or both. The minimum output signals required for rotational viscometry are torque, rotational speed, temperature, and time.
NOTE 5 - Manual observation and recording of data are acceptable.
6.1.6 Temperature measuring device, to provide an indication of the specimen temperature over their range of 100 °C to 200 °C to within +/- 0.2 °C.
6.1.7 Stand, to support, level, and adjust the height of the drive motor, shaft and rotational element.
6.1.8 Specimen container, fitted with an insulated cover, to contain the test specimen during testing.
6.1.9 Auxiliary instrumentation considered necessary or useful in conducting this method includes:
6.1.9.1 Data analysis capability to provide viscosity, stress, or other useful parameters derived from measured signals.
6.1.9.2 Level to indicate the vertical plumb of the drive motor, shaft, and rotational element.
6.1.9.3 A guard to protect the rotational element from mechanical damage.
6.2 Temperature Bath and precision proportional temperature controller that provides a controlled isothermal temperature environment over the range of 100 °C to 200 °C (212 °F to 392 °F) constant to accuracy of +/- 1.0 °C (1.8 °F).
6.3 Graph paper, semi-logarithmic.
