Polyester chip for producing compound filament with ultralow melting point and preparation method thereof

Abstract

The invention discloses a polyester chip for producing a compound filament with ultralow melting point and a preparation method thereof. The preparation method specifically comprises the following steps: 1) compounding a polyester chip substrate with ultralow melting point: utilizing an intermittent polymerization reaction device to finally compound a target polyester chip substrate with intrinsicviscosity of 0.750-0.770dl / g, by introducing an isomeric monomer into primary esterification reaction, introducing a blending modified additive and ingredients into secondary esterification reactionand controlling reaction temperature and vacuum degree in the stage of condensation polymerization; 2) pre-crystalizing the polyester chip: adopting a solid-phase boiling crystalizing technology for treating the product compounded in step 1, thereby finishing the pre-crystalizing of polyester chip; 3) drying the pre-crystalized polyester chip: adopting a temperature-control vacuuming processing technology for treating the pre-crystalized polyester chip acquired in step 2), thereby finishing the drying of polyester chip. After the ending of drying, the water content of polyester chip is not above 0.03% and the intrinsic viscosity is not below 0.730dl / g. The polyester chip for industrially producing the compound filament with ultralow melting point can be prepared through the three steps.

Description

technical field [0001] The invention relates to a polyester chip and a preparation method thereof, in particular to a polyester chip for producing ultra-low melting point composite filaments and a preparation method thereof. Background technique [0002] Polyester sheath-core low-melting point composite spinning is mostly used in the production of non-adhesive composite non-woven fabrics. Because it does not use adhesives, it meets the market's requirements for low-carbon environmental protection. The application range and usage are expanding year by year, and it is becoming more and more popular. Recognition in the domestic market. Although this kind of fabric has been developed abroad for a long time, due to the complicated raw material synthesis process and high production cost in the early stage, few people in China have set foot in raw materials, especially polyester chips for ultra-low melting point fibers. There are few domestic manufacturers that can produce them. A...

AI Technical Summary

Problems solved by technology

[0004] 1. Ordinary low-melting point modified polyester chips have a wide amorphous region, which is not conducive to subsequent drying and crystallization treatment;

[0005] 2. General low-melting point modified polyester chips, the reliability of the bonding treatment after spinning is not high, and the durability of the finished product is poor;

[0006] 3. In general boiled crystallization, the process control is unstable, the crystallinity cannot be guaranteed, and the intrinsic viscosity fluctuates greatly, and the follow-up practicability is poor;

[0007] 4. Low-melting point polyester chips are difficult to dry, easy to agglomerate and agglomerate, and the intrinsic viscosity is easily affected. The traditional low-temperature air-drying method cannot fully dry low-melting point polyester chips, which will cause the extrusion pressure to be unstable during the spinning process. Floating wires, broken wires, etc. are not conducive to continuous production

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