1. Name: Pour Point
2. Method summary: After the sample is cooled, check the fluidity of the sample every 3°C, and record the lowest temperature at which the sample can flow as the pour point.
3. Operation method
①Pour the sample into the dry and clean test tube to the ring mark, fix the thermometer in the center of the test tube with a stopper, make the bottom of the thermometer bubble 8 mm～10 mm from the bottom of the test tube, and then inject 1 mL～ into the bottom of the sleeve. 2 mL of absolute ethanol.
Then put the test tube into the sleeve to form the test tube assembly.
②Immerse this test tube assembly in the prepared cooling bath. From the first observation of the fluidity of the sample, the fluidity of the sample should be observed every time the temperature drops by 3°C, paying special attention not to disturb the lumps in the sample. The thermometer should not be moved after the sample is cooled enough to form paraffin crystals. When the temperature is low, the condensed water mist will hinder the observation. You can wipe the test tube with a cleaning cloth moistened with a wiper close to the temperature of the cold bath to remove the outer surface Water mist.
③When the test tube is tilted and the sample does not flow, immediately place the test tube in a horizontal position for 5 seconds (measured with a timer), and carefully observe the surface of the sample. If the sample shows any movement, immediately put the test tube back into the bath Or in the casing, when the temperature is lowered by 3°C, re-observe the fluidity of the sample.
④ Operate in this way until the test tube is placed in a horizontal position for 5 seconds and the sample in the test tube does not move. Record the thermometer readings observed at this time, and add 3°C to the recorded result as the pour point or lower Pour point.
