Polyester POY: Structure and performance shaping under high-speed spinning process

Polyester POY, full name polyester pre-oriented yarn, is a semi-finished form of polyester fiber. It is mainly made of polyester chips (PET chips) through a series of complex processing processes, and finally presents a filament with a specific orientation and certain strength. As an important link in the textile industry chain, POY can not only be directly used for subsequent processing, such as adding elasticity to make DTY (polyester stretch deformation yarn), but also can be used as a raw material for other textiles, and is widely used in clothing, home textiles, industrial fabrics and other fields.

In the production process of polyester POY, high-speed spinning is undoubtedly the most critical link. This step not only determines the initial structure of POY, but also has a profound impact on its subsequent performance. The basic principle of high-speed spinning is to extrude the molten polyester melt through a precisely designed spinneret plate, and quickly cool and solidify under the action of high-speed airflow or mechanical stretching, thereby forming a pre-oriented yarn with a certain degree of orientation.
Melt preparation: Before high-speed spinning, the polyester chips need to be pretreated first, including drying, melting and filtering steps to ensure the purity and fluidity of the melt.
Spinning process: The melt is fed into the spinning box and extruded through a precise spinneret. During the extrusion process, the melt is stretched and cooled by the high-speed airflow and quickly solidified into filaments. In this process, the control of parameters such as spinning speed, temperature, and stretch ratio is crucial, and they directly determine the orientation and structure of POY.
Cooling and solidification: The extruded melt filaments are rapidly cooled in the spinning box to form semi-solid fibers. The cooling speed and method directly affect the crystallinity and orientation of the fiber, and thus affect the performance of POY.
Winding and collection: The POY filaments after cooling and solidification are fed into the winding machine, and after stretching, shaping and other treatments, they are finally wound into a certain specification of bobbin yarn for subsequent processing and use.

High-speed spinning technology has a profound impact on the structure and performance of polyester POY. It is mainly reflected in the following aspects:
Improvement of orientation: During high-speed spinning, under the action of high-speed stretching and cooling, the molecular chain of the melt is oriented along the stretching direction, forming a fiber structure with a certain degree of orientation. This oriented structure not only improves the strength and modulus of the fiber, but also gives POY good dimensional stability and thermal stability.
Control of crystallinity: The optimization of cooling speed and method can regulate the crystallinity of POY. Appropriate crystallinity helps to improve the heat resistance and wear resistance of the fiber while maintaining good softness and processability.
Balance of fiber properties: By precisely controlling spinning parameters such as spinning speed, temperature, stretch ratio, etc., balanced optimization of fiber properties can be achieved. For example, increasing the spinning speed can increase the orientation and strength of the fiber, but too high a speed may cause the fiber surface to be rough, affecting subsequent processing. Therefore, it is necessary to adjust the parameters according to specific needs to achieve the best performance balance.
Adaptability to subsequent processing: POY produced by high-speed spinning has good processability and is easy to carry out subsequent stretching, stretching, dyeing and other treatments. This adaptability enables POY to be widely used in the production of various textiles to meet the needs of different fields.
IV. Application and development trend of polyester POY
Polyester POY occupies a pivotal position in the textile industry with its unique properties and wide application fields. It can not only be directly used to make various clothing fabrics and home textile products, such as shirts, skirts, bedding sets, etc., but also be used as raw materials for other textiles, such as industrial fabrics, carpets, filter materials, etc. With the continuous advancement of textile technology and the increasing diversification of consumer demand, the application field of polyester POY is constantly expanding.