Below we will introduce the rubber additive initial melting point test, according to the type of instrument and the degree of automation to list different instruments and principles of the difference in the test results. In order to express more directly the influence of different instruments on the test results, we took MBT, a rubber accelerator, as an example. After the sample of the same batch was mixed evenly with the four-part method for several times, 200g of the sample was taken as a unified sample, and the tester fixed and tested its initial melting point with different instruments.
1. B tube instrument method
1.1 Capillary tube was used for sample injection. Capillary tube specifications: inner diameter of 1.2-1.4mm and wall thickness of 0.2-0.3mm.
1.2 Heating method: liquid heat conduction oil can be used, such as liquid paraffin, sulfuric acid, 201 methyl silicone oil, dioctyl phthalate or mixed solution of sulfuric acid and potassium bisulfate.
1.3 Degree of automation: manually detect and visually observe the melting point.
1.4 Factors influencing melting point results: capillary specification, 3-6mm compression height of capillary samples, rate of temperature rise, preset temperature (the temperature at which the sample is placed).