Method for quickly measuring viscous flow activation energy of polyolefin

Abstract

The invention relates to a method for quickly measuring the viscous flow activation energy of polyolefin, which is used for measuring the viscous flow activation energy of polyolefin such as polyethylene, polypropylene, and the like. The method comprises the following steps of: carrying out temperature scanning at a temperature above the smelting point of polyolefin and below a decomposition temperature by using a dynamic rheometer to measure a plurality of change curves of the viscosity changed along with the temperature of the polyolefin; converting a measurement result into change curves of the apparent viscosity changed along with the temperature of a sample through a Cox-Merz rule; carrying out linear regression on the converted data by using a formula of lgeta=K / T+b to obtain the values of K and b in the regression formula; and then obtaining the viscous flow activation energy of the measured sample according to a formula of Eeta=19.147*(J / mol). The method has the advantages of fewer required samples, short measurement period, high speed and high efficiency.

Description

technical field [0001] The invention relates to an analysis method of polyolefin, in particular to a method for measuring activation energy of polyolefin viscous flow. Background technique [0002] At present, the domestic plastics industry has formed a relatively complete system from raw material production, product processing and manufacturing to application, but the research on rheological properties of plastic processing is relatively lagging behind, and many small and medium-sized enterprises still rely on experience for production. The precise setting of plastic processing parameters directly affects the appearance quality and internal performance of the product, so the research on the rheological properties of raw materials has a direct guiding effect on the production of plastic products. The activation energy of viscous flow is an important parameter of the rheological properties of materials. It not only reflects the difficulty of material flow, but more importantl...

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Problems solved by technology

[0014] The above calculation process requires special calculation software, such as Rhios V.4.4.4

In addition, to obtain the activation energy of viscous flow, multiple tests at different temperatures are also required, and the efficiency is not high.

[0015] It can be seen that the principles of the two commonly used methods for measuring the activation energy of viscous flow are based on the Arrhenius empirical formula. To obtain the desired results, multiple experiments are required first, and the measurement efficiency is not high.

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