A kind of controllable degradation recovery method of polyurethane

Abstract

The present invention provides a controllable degradation and recovery method of polyurethane. The method is characterized in that controllable degradation of waste polyurethane is carried out in an eutectic solvent, and the obtained degradation products are separated and purified to obtain a polymer polyol and an amine. The method avoids pollution of burying and burning to soil, water and air, avoids the defect that only chemicals with low added values can be obtained by physical crushing, and also avoids the harms of toxic gases generated by heat treatment. A degradation system used in the method is the eutectic solvent, the controllable degradation can be achieved by selectively breaking bonds of polyurethane without adding other catalysts, the preparation method and the use process ofthe degradation system are green, environmentally friendly, economical and saving, and can be recycled, and the degradation products obtained by the method are easy to separate, and are convenient torecover.

Description

technical field [0001] The invention belongs to the field of recycling organic polymer materials, and in particular relates to a controllable degradation and recycling method of polyurethane. Background technique [0002] As the sixth largest synthetic material, polyurethane is widely used in automobiles, refrigerator manufacturing, transportation, civil engineering, shoes, synthetic leather, fabrics, aviation, medical treatment, petrochemical and other fields. From 2008 to 2014, the global annual output of polyurethane was from From 16.3 million tons to 21 million tons, the global annual output of polyurethane will reach 28.6 million tons in 2018, resulting in a large amount of solid waste pollution. Therefore, there are many researches on the degradation and recycling methods of polyurethane. The recycling methods of polyurethane generally include burial, incineration, physical crushing, heat treatment and chemical treatment: burying will cause soil and water pollution; in...

AI Technical Summary

Problems solved by technology

These polyurethane degradation methods have been studied and applied to a certain extent, but there are also some problems, such as the relatively harsh reaction conditions required by the hydrolysis method and the alcoholysis method, the need to add a catalyst and the catalyst cannot be recycled, and the mixture after the aminolysis method is degraded Monomers are difficult to separate in the degradation system. The acid hydrolysis and alkaline hydrolysis methods have relatively large environmental pollution and high degradation costs. The thermal degradation method has great environmental pollution and can only obtain products with low chemical added value.

When these methods are used for degradation, because the chemical bond breakage of polyurethane is not selective, the degradation products are generally difficult to separate and have low chemical added value.

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