Preparation method of high barrier light-proof, preservative and environment-friendly polyester material

Abstract

The invention relates to a preparation method of high barrier light-proof, preservative and environment-friendly polyester material. The method comprises the following technical processes: 1) performing preliminary modification of montmorillonite to obtain organized montmorillonite loaded with main titanic type catalyst; 2) selecting proper branching agent; 3) performing esterification; 4) performing polycondensation, wherein firstly the expanded montmorillonite loaded with titanium and stable other metal composite catalyst and branching agent are separately dissolved in ethanediol to obtain additives, the additives are injected through an additive nozzle, polyphosphoric acid is injected through another nozzle, the dosage is subject to the content in polyester, a gear pump is used to inject the esterified oligopolymer along with the above additives in the pipeline in a prepolymerizer; the prepolymerizer is an upflow bubble tower; and when reaching the top of the prepolymerizer, the material flows to a final polycondensation autoclave, and the product is filtered by a melt filter and then pulled to a pelleter to prepare polyester slices; and 5) tackifying solid phase. The method of the invention can provide the high barrier light-proof, preservative and environment-friendly polyester material.

Description

(1) Technical field [0001] The invention relates to a preparation method of polyester material. It is mainly used in the packaging of PET beer bottles. It can also be used as a packaging material for other soft drinks, tea drinks, fruit juices, medicines, food and other packaging containers. It belongs to the application technical field of packaging materials and engineering plastics. (2) Background technology [0002] Polyethylene terephthalate (PET) is the most important polyester at present. It has high heat resistance, good chemical resistance and insulation, and is widely used in fibers, biaxially stretched films And polyester bottles and various packaging containers. In today's engineering plastics market, PET has a tendency to replace PBT due to its excellent cost performance. In the field of packaging materials, especially in the field of bottle packaging materials, PET is developing rapidly. In 1973, the industrialization of the patented technology of biaxially...

AI Technical Summary

Problems solved by technology

However, the defect that exists at present is that the existing PET / MMT nanocomposite materials only use conventional organic methods to modify montmorillonite, and the prepared PET / MMT nanocomposite materials are intercalation type, and MMT is not completely peeled off. The dispersion in the matrix is ​​poor, and the PET / MMT nano-bottles made after injection molding and blowing processing have poor barrier properties and transparency, which hinders the application of PET / MMT nanocomposites in the field of high barrier materials

[0012] Analysis of the above main reasons is that the dispersion of montmorillonite in the PET matrix is ​​poor, agglomeration occurs, the sheets cannot be uniformly dispersed and arranged regularly, and the role of labyrinth sealing cannot be achieved, so the barrier property is poor

In addition, due to the secondary agglomeration phenomenon in the process of injection molding and bottle blowing, the barrier and transparency of beer bottles are poor.

In addition, in the process of injection molding preform and bottle blowing of PET / MMT nanocomposites, due to the shear force in the screw extrusion process and the bidirectional tensile force in the blow molding process, montmorillonite and Stress concentration occurs between the PET matrix interface, which causes microcracks, and even material damage and delamination, resulting in a decrease in the transparency and barrier properties of the blown bottle

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