METHOD FOR STUDY OF ORGANIC SUBSTANCES, MOSTLY CHARACTERISTICS OF OXIDATIVE THERMAL DESTRUCTION OF ORGANIC POLYMERS Russian patent published in 2023 - IPC G01N31/12 

FIELD: research of thermal degradation of organic polymers.

SUBSTANCE: method for studying the characteristics of oxidative thermal degradation of polymeric materials, predominantly organic polymers, includes placing the analysed sample in a reactor, constantly passing an air stream through the reactor, conducting thermal degradation with subsequent determination of its characteristics. The analysed sample is moved in the reactor along the furnace with a temperature gradient from room temperature to high temperature while maintaining the sample heating rate, which is from 5°C to 100°C per minute, carried out based on a computer program for moving the sample along the furnace, taking into account the results of continuous monitoring of its temperature. The oxygen concentration in the air stream is determined at the reactor inlet. The magnitude of the change in the concentration of oxygen is determined at the outlet of the reactor. The breakthrough of non-oxidized molecules of organic polymers evaporated from the analysed sample at the outlet of the reactor is prevented by trapping them on the catalyst. According to the data obtained, the dependency of the change in the oxygen content on the temperature of the sample in the air flow is identified. The dependency is processed by approximating the oxygen concentration in the air flow determined at the furnace inlet with a straight line and approximating the leading edge of the oxygen content reduction dependency in the air flow at the reactor outlet with a straight line. The temperature coordinate of the point of intersection of these lines determines the temperature of the onset of thermal degradation of the organic polymer.

EFFECT: simplification of the method and an increase in the accuracy of determining the initial temperature of the oxidative thermal degradation of the organic polymer.

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