A kind of preparation method of cationic dyeable regenerated cotton-like polyester fiber

Abstract

The invention relates to the field of polyester synthesis, and discloses a method for preparing recycled cotton-like polyester fibers dyeable by cationic dyes, comprising: 1) sodium isophthalate pentasulfonate, dimethyl isophthalate-5 ‑Sodium benzenesulfonate or a mixture of the two is esterified with ethylene glycol, and then polyethylene glycol is added to react to obtain a three-monomer esterified product; 2) Sorting and crushing of recycled polyester; 3) Recycling The polyester is mixed with the reaction auxiliary agent, and then melted and extruded with the esterification of the three monomers to obtain recycled polyester chips; 4) Spinning. The present invention does not need to degrade the recycled polyester, but directly reacts the recycled polyester with the modified three-monomer esterified product and the reaction auxiliary agent to prepare the recycled polyester, which has the advantages of simple process and low cost, and because The polyester molecular chain contains a modified three-monomer ester block, which makes the fiber have excellent moisture regain and cationic dyeing effect, and achieves a cotton-like effect.

Description

technical field [0001] The invention relates to the field of polyester synthesis, in particular to a method for preparing regenerated cotton-like polyester fibers dyeable by cationic dyes. Background technique [0002] Polyethylene terephthalate (PET), as the most widely used synthetic resin in the world, is widely used in beverage bottles, chemical fibers, films, sheets and other fields. In the past ten years, the global demand for polyester has increased sharply, and the scale and number of polyester production enterprises have maintained rapid growth. In 2018, domestic polyester production exceeded 50 million tons. Polyester production not only needs to consume a large amount of precious petroleum resources, but also with the rapid increase in the consumption of polyester products, the impact of various waste polyester products and polyester waste on the environment The problem of pollution has become increasingly prominent. Therefore, recycling polyester products can n...

AI Technical Summary

Problems solved by technology

Chemical method: mainly through hydrolysis, methanolysis, ethylene glycol alcoholysis and other methods, the waste polyester is decomposed into polyester raw materials or intermediates through chemical treatment, so as to achieve the purpose of repeated use, but the chemical method requires high technology , Recycling costs are high, which limits the large-scale application of polyester chemical recycling and regeneration methods

[0004] Invention patent CN 107652422A discloses a method for preparing regenerated cationic dyeable polyester by alcoholysis of waste polyester, the method is through alcoholylysis of waste polyester and then with isophthalic acid-5-sodium sulfonate and polyethylene glycol Alcohol is used to prepare regenerated cationic dyeable polyester fibers. The disadvantage of this method is that the content of diethylene glycol in the prepared cationic dyeable polyester fibers is as high as 5.5±0.3%, and the melting point is low, which is not conducive to spinning and dyeing stability.

Invention patent CN 103132175A discloses a regeneration-based cationic dyeable polyester filament and its preparation method, which uses a composite catalyst to depolymerize waste polyester to obtain high-yield ethylene terephthalate (BHET) by adding treated The isophthalic acid-5-sodium sulfonate slurry is polymerized in situ to prepare dyeable polyester with regenerated cationic dyes. The disadvantages of this scheme are that the process flow is long and complicated, the separation and purification of degradation products (BHET) are difficult, and the modification High monomer usage (0.5%-10%), resulting in higher cost of recycled products