How is polyester fiber made?

How is polyester fiber made? -- Detailed analysis from raw material to finished product

polyester fiber is a widely used synthetic fiber and is favored for its excellent properties. How is polyester fiber made? This article will analyze the production process of polyester fiber in detail from the key links such as raw material preparation, polymerization reaction, spinning and forming.

1. raw material preparation: polyester fiber basic composition

The main raw materials of polyester fiber are terephthalic acid (PTA) and ethylene glycol (MEG). PTA is an important chemical raw material, usually obtained from purified terephthalic acid. Ethylene glycol, on the other hand, is a colorless liquid that is widely used in polyester production and other chemical industries. These two raw materials play a key role in the production of polyester fibers.

In the raw material preparation stage, PTA and MEG need to be strictly purified and proportioned. The purity of PTA directly affects the performance of polyester fiber, so it is necessary to dehydrate and decolorize PTA during the production process to ensure that it meets the standard requirements. MEG also needs to go through distillation and other processes to remove impurities and ensure its purity and quality.

2. polymerization: Polyester fiber core process

The production process of polyester fiber mainly depends on the polycondensation reaction. In the polycondensation reaction, PTA and MEG react under specific conditions to produce polyester chips (PET). This process is usually divided into two steps: esterification and polyesterification.

1. Esterification: Esterification is the first step in the production of polyester fibers. In the esterification reaction, PTA and MEG react under the action of a catalyst to produce an esterified compound. This reaction needs to be carried out at high temperature, high pressure and a certain degree of vacuum to ensure the smooth progress of the reaction. The product of the esterification reaction is a low molecular weight polyester that provides the basis for the subsequent polyesterification reaction.

2. Polyesterification reaction: Polyesterification reaction is a key step in the production of polyester fibers. At this stage, the products of the esterification reaction are further reacted to form high molecular weight polyester chips (PET). The polyesterification reaction is generally carried out at higher temperatures and pressures and for longer reaction times. Through this process, the molecular weight of the polyester gradually increases, and finally a polyester chip with excellent properties is formed.

3. Spinning: Polyester Fiber Final Form

The polyester chips go through a spinning and forming process to eventually become what we know as polyester fibers. The spinning process is to melt the polyester chips and spray them out through the spinning nozzle to form slender fiber filaments. The spinning process requires precise control of temperature, pressure and spinning speed to ensure fiber uniformity and consistency.

After the spinning is completed, the filament needs to go through the steps of cooling, drawing and coiling. The cooling process usually uses air or water cooling to quickly cool and solidify the fiber filaments. Subsequently, the fiber yarn is subjected to a drawing treatment to further improve its strength and toughness. Filaments are coiled into a form, such as a bundle or spool, for subsequent processing and application.

4. polyester fiber application and advantage

Polyester fiber is widely used in clothing, home textiles, industrial materials and other fields because of its excellent performance. It has the advantages of high strength, wear resistance, good wrinkle resistance and easy dyeing, and has become an indispensable material in the modern textile industry.

5. summary: Polyester fiber production process

The production process of polyester fiber can be simply summarized as three main stages: raw material preparation → polymerization reaction → spinning. From the preparation of raw materials for PTA and MEG, to the polymerization process of esterification and polyesterification, to the final form of spinning molding, every link is crucial. Through scientific production technology and strict quality control, polyester fiber not only has excellent performance, but also provides important support for the development of modern textile industry.

The production process of polyester fiber is a complex and precise chemical synthesis process. From the selection of raw materials to the molding of the final product, every step requires precise control and strict management. With the continuous progress of science and technology, the production technology of polyester fiber is also constantly optimized, bringing more convenience and comfort to our lives.