This standard specifies the test method for shear stability of polymer containing liquid by adopting the ultrasonic shear method.
This standard is applicable to the polymer containing hydraulic fluids and internal combustion engine oil.
2 Normative References
GB/T 265 Petroleum Products-Determination of Kinematic Viscosity and Calculation of Dynamic Viscosity
GB 1992 Solvent Naphthas
3 Method Summary
Adequate amount of polymer containing test specimen shall be placed on the contacting rod of amplitude transformer for ultrasonic shear treatment in fixed time by one time or several times, and the variance in viscosity shall be determined according to GB/T 265, at last, the decrease rate of the sample shall be calculated.
The shear stability shall be assessed according to viscosity decrease rate of the fluid caused by ultrasonic shear action in the amplitude transformer (namely, ultrasonic oscillator).
4 Instruments and Materials
4.1 Instruments
4.1.1 Ultrasonic shear tester: output end of the amplitude transformer for ultrasonic shear test is arranged as a cylindrical rod with a diameter of 20mm, its end surface shall not be punched with center hole and chamfered for angles, the surface roughness shall not be less than , the resonant frequency shall be 20kHz±1kHz, and the output power shall be larger than or equal to 250W.
Note: the ultrasonic shear device of type CSJ-III shall be produced by Kaifeng Second Instrument Factory.
4.1.2 Stopwatch: the scale interval shall be 0.2s.
4.1.3 Measuring cylinder: 50mL.
4.1.4 Beaker: 100mL.
4.1.5 Thermometer: bar thermometer of 0 ~ 100℃.
4.1.6 Viscosity tester: the viscometer and thermostatic waterbath in accordance with the requirements of GB/T 265.
4.2 Materials
Reference fluid: CSJ-Standard No.2 oil, the viscosity decrease rate shall be 16%±1% under standard shear test conditions (namely, the test specimen amount shall be 30mL, the cooling water temperature shall be 38℃ and the shearing duration shall be 10min).
Note: the CSJ-Standard No.2 oil shall be provided by the Research Institute of Petroleum Processing (RIPP).
5 Reagents
Petroleum ether: analytically pure, 60~90℃ (or the solvent naphthas in accordance with the requirements of No.90 in GB 1992).
