PET resin fast and easy to process and preparing method thereof

Abstract

The invention discloses a preparing method of resin fast and easy to process. The preparing method includes the steps that basic slices obtained through esterification and polycondensation of mixed slurry of glycol and terephthalic acid are crystallized in advance at the temperature of 150-165 DEG C and are crystallized at the temperature of 200-210 DEG C, the crystallization degree reaches 50-52%, the obtained crystallized slices are reacted for 8-10 hours at the temperature of 210 DEG C, viscosity reaches 0.82 dl / g or higher, pentaerythritol is added after the crystallized slices are cooled, fusion and granulation are conducted through a screw extruder, cooling in water is conducted, the obtained fused and granulated PET slices are crystallized in advance at the temperature of 150-165 DEG C and are crystallized at the temperature of 200-210 DEG C, the crystallization degree reaches 50-52 %, the obtained slices are reacted for 6-8 hours at the temperature of 210 DEG C, and viscosity reaches 0.88 dl / g or higher. Compared with other high-viscosity PET resin production methods, the molecular weight of the resin has the advantages of being narrow in distribution and even overall, and the mechanical performance of the resin is superior to that of existing PET resin with the same viscosity.

Description

technical field [0001] The invention belongs to the field of resins, and in particular relates to a fast and easy-to-process PET resin and a preparation method thereof. Background technique [0002] Polyethylene terephthalate is referred to as PET. It has excellent physical and mechanical properties in a wide temperature range. The long-term use temperature can reach 120 ° C. It has excellent electrical insulation and good dimensional stability. It is widely used in synthetic fibers. , food packaging, various films, plastic alloys and other fields. [0003] Due to the different application fields of PET synthesis, the requirements for the intrinsic viscosity index of the resin are also different. In plastic alloys, engineering plastics, and strapping, PET is required to have a higher intrinsic viscosity. [0004] In the prior art, ordinary PET resin is generally used to add a chemical chain extender through a screw extruder during processing to increase the intrinsic viscos...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that the chemical chain extender is unevenly distributed in the resin, which may easily cause low local viscosity, resulting in differences in the mechanical strength of the product, and the addition of the chain extender will bring food safety risks, which limits the method. Applications in some fields