Method for detecting ethylene or ethylene propylene rubber content in ethylene-propylene copolymerization polypropylene

Abstract

The invention discloses a method for detecting the content of ethylene or ethylene propylene rubber in ethylene-propylene polypropylene, comprising the steps of obtaining the raman spectrum of an ethylene-propylene polypropylene sample containing known ethylene or ethylene propylene rubber, preprocessing the raman spectrum, conducting correlation modeling through presetting the content of the known ethylene or ethylene propylene rubber and the intensity of the raman spectrum which corresponds to the raman spectrum characteristic wave number set (RCS) so as to obtain a predicted model, detecting the raman spectrum of the ethylene-propylene polypropylene sample to be detected and preprocessing the raman spectrum, guiding the intensity of the raman spectrum of the ethylene-propylene polypropylene sample to be detected, which corresponds to the RCS into the predicted model so as to detect the content of the ethylene or ethylene propylene rubber in the ethylene-propylene polypropylene sample to be detected, and finally reconstructing the RCS through selecting the characteristic of the raman spectrum in the light of the actual situation. The invention has the advantages of convenience, rapidness, accuracy, environmental protection, and the like and can be used for detecting the content of the ethylene or ethylene propylene rubber in ethylene-propylene polypropylene on line or off line during the manufacturing and the production processes of the ethylene-propylene polypropylene.

Description

technical field [0001] The invention relates to the field of Raman spectrum detection, in particular to a Raman spectrum detection method for the content of ethylene and ethylene-propylene rubber in ethylene-propylene copolymerized polypropylene. Background technique [0002] Polypropylene (PP for short) is a polymer obtained by polymerizing propylene as a monomer, and is an important variety of general-purpose plastics. However, the impact toughness of homopolypropylene is low, especially its brittleness at low temperature greatly limits its use. Therefore, people modify it by adding tough materials to blend or copolymerize it to effectively improve the performance of polypropylene. Make polypropylene more widely used. [0003] In ethylene-propylene copolymerized polypropylene, the addition of ethylene can introduce ethylene-propylene rubber to improve the impact resistance of the product. However, the content of ethylene in the copolymer and the content of ethylene-propy...

AI Technical Summary

Problems solved by technology

Among them, the chemical analysis method, radioisotope method and model compound method are cumbersome, time-consuming and labor-intensive, and cannot be applied to the online detection of polypropylene; the homopolymer blending method is rarely used due to large measurement errors; the chemical extraction method not only consumes It takes a long time, and the organic solvent used in the extraction process may also cause environmental pollution; the equipment required for the nuclear magnetic analysis method is large in size and high in purchase costs. At the same time, the nuclear magnetic equipment requires high operating conditions and complicated equipment maintenance. The personnel bring a lot of inconvenience; the sample detection of the infrared analysis method requires the sample preparation of the mold, and the online detection cannot be realized

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