0102030405
Polyester film, often referred to as polyethylene terephthalate (PET) film
Polyester film, often referred to as polyethylene terephthalate (PET) film, is a versatile polymer-based material known for its exceptional combination of properties that make it suitable for a wide range of applications across various industries, including chemical, electronic, food packaging, and more .
Key properties of polyester film include:
- Optical Properties: Polyester film is typically transparent and colorless, with a glossy finish. It has a high refractive index of 1.6 and offers excellent transparency, with some grades providing transparency of 85% or more .
- Dimensional Stability: It exhibits low shrinkage, around 2%, when exposed to heat, and has a low coefficient of linear thermal expansion, which contributes to its stability in varying temperatures .
- Physical and Chemical Properties: Polyester film has high strength, rigidity, and toughness. It resists punctures, abrasion, and temperature extremes, both high and low. It is also chemically resistant, impervious to oils, airtight, and capable of retaining aromas .
- Chemical Resistance: Polyester film is resistant to a variety of chemicals, including alcohols, hydrocarbons, and many acids. It is partially resistant to some chlorinated hydrocarbons and not resistant to certain phenol derivatives .
- Permeability: It provides a good barrier to gases and vapors, making it suitable for applications requiring protection from environmental factors .
The manufacturing process of polyester film involves several steps:
1. Raw Material Preparation: The main raw materials are terephthalic acid and ethylene glycol, which are mixed in a certain molar ratio along with catalysts and stabilizers .
2. Polymerization Reaction: Under high temperature and pressure, esterification and condensation reactions occur to form polyester polymers .
3. Melt Extrusion: The polyester polymer melt is extruded through an extruder head to form a sheet material .
4. Biaxial Stretching: The extruded sheet undergoes longitudinal and transverse stretching to increase its strength and toughness .
5. Heat Treatment: This process eliminates internal stress and improves dimensional stability .
6. Winding: The heat-treated sheet is wound to obtain the final polyester film product .
In summary, polyester film is a high-performance material with a balance of optical, physical, mechanical, thermal, and chemical properties. Its manufacturing process ensures its utility in applications such as packaging, insulation, and industrial films, where its strength, clarity, and resistance to environmental factors are critical .
Leave Your Message
description2