Tackifying spinning process for regeneration of waste polyester

Abstract

The invention relates to the technical field of regenerated polyester preparation processes, in particular to a tackifying spinning process for regeneration of waste polyester. The waste polyester is recycled and regenerated, so that the molecular weight of the polyester melt is increased, devolatilization with large specific surface area can be carried out to achieve polycondensation tackifying, meanwhile, low-molecular-weight impurities are gasified and removed, and therefore the melt viscosity is increased; impurities in the polyester melt can be effectively removed, so that the grade of prepared polyester fibers is improved; the pressure of melt filtering before spinning can be effectively reduced; the technological process is relatively short, and the cost is relatively low; meanwhile, in a melt state, the tackifying amplitude is more uniform than that of a solid-phase tackifying method, the molecular weight distribution is narrow, and the product quality is more stable; moreover, the prepared polyester fibers have excellent antibacterial performance, the service life of the polyester fibers is effectively prolonged, and the quality of the polyester fibers is improved.

Description

technical field [0001] The invention relates to the technical field of preparation technology of recycled polyester, in particular to a viscosity-increasing spinning process for recycling waste polyester. Background technique [0002] Although the physical method has many advantages in the preparation of recycled polyester, there are still many unavoidable shortcomings, the most notable of which is that the physical method regeneration belongs to downgrading regeneration, so for the regeneration of waste polyester textiles with a lot of impurities , it is impossible to prepare qualified recycled polyester fibers only by simple melt extrusion of waste materials, so the improvement of the quality of recycled polyester melt is the core link in the physical regeneration process. Improving the quality of the recycled melt mainly includes the thickening and impurity removal of the melt. There are mainly three ways to achieve polyester viscosity increase: solid-state polycondensat...

AI Technical Summary

Problems solved by technology

In addition, special attention should be paid to the fact that the water content in the raw material before liquid phase thickening must be less than 100ppm is also a very critical factor, because the hydrolysis reaction speed of polyester melt is several times higher than the thermal degradation reaction speed in the high temperature reaction stage, Therefore, if the drying of the raw material does not meet the standard, it will lead to the failure of regeneration and thickening

Another commonly used polyester melt viscosity-increasing technology is the chemical chain extension method, which usually uses a highly active bifunctional small molecule compound that can add or condense with the polyester end group as a chain extender, so that the polyester molecule Linking, the molecular weight doubles, but for the recycled polyester melt with more impurities, the addition-type chain extender is generally used to obtain a better viscosity-increasing effect than the condensation type, because the condensation-type chain extender expands the chain at the same time It will also release small molecular products, if not eliminated in time, it will also cause deterioration of the melt

Furthermore, the antibacterial properties of recycled polyester products are poor, which not only affects their service life, but also affects their quality.

Images