The phenomenon of movement of organic matter (polypropylene) in a temperature field

In the process of studying the oxidative thermal degradation of polypropylene by the method of oxythermography, the phenomenon of movement of matter in a gradient temperature field was discovered. When the sample was introduced into a high-temperature reactor, being in a gradient temperature field, the sample passed into a liquid state, and then in the form of a drop remains on the surface of the quartz tube of the boat holder, where the sample was placed. The drop in space remained in place, and the boat holder to which the drop was attached moved. A drop relative to a quartz tube moves from an area with a high temperature to an area with a lower temperature.