polyethylene terephthalate: The Complete Guide to Types, Properties, Uses & Price

Plastics have become an essential part of modern life due to their versatility, durability, and cost-effectiveness. Among the wide range of polymers used across different industries, polyethylene terephthalate(PET) stands out as one of the most widely used thermoplastic polymers. It is extensively used in beverage bottles, food packaging, polyester fibers, films, and a variety of industrial applications due to its excellent mechanical strength, chemical resistance, transparency, and recyclability.

What Is PET?

Polyethylene Terephthalate(PET) is a type of plastic polymer that is widely used in everyday products and industrial applications. It is strong, lightweight, transparent, and resistant to many chemicals, which makes it particularly useful for packaging, bottles, food containers, films, and synthetic fibers. In simple terms, PET is a plastic material that can be processed into different forms depending on the application.

PET in the World of Polymers

Interestingly, in the fascinating world of polymers, PET belongs to the polyester family of polymers. More specifically, it is a thermoplastic polyester, meaning it can be heated, melted, shaped, and processed again. Its combination of strength, clarity, dimensional stability, and relatively good chemical resistance has made it one of the most widely used polymers in the packaging, textile, and industrial sectors. The PET structure is based on repeating units containing aromatic rings and ester groups, which contribute to many of its characteristic properties.

What Is the Difference Between PET and Polyester?

At this point, you may wonder: If PET is a type of polyester, what is the difference between PET and the broader term “polyester”? The simplest answer is that polyester is a broad family of polymers, while PET is one specific type of polyester. Polyester refers to polymers that contain ester groups in their molecular backbone, while PET specifically refers to polyethylene terephthalate, a polyester produced mainly from ethylene glycol and terephthalic acid. Therefore, all PET is polyester, but not all polyester is PET.

How Is PET Made?

Polyethylene Terephthalate is produced through a controlled chemical process in which specific raw materials are converted into long polymer chains with the required molecular weight and properties. The process mainly uses PTA(Purified Terephthalic Acid) and MEG (Monoethylene Glycol), while DMT(Dimethyl Terephthalate) can also be used as an alternative raw material. Through esterification or transesterification followed by polycondensation, the resulting PET polymer is eventually processed into forms such as chips or pellets for different applications.

PET Polymerization Process

The PET production process involves several main stages that ultimately lead to the formation of polymer chains with the appropriate molecular weight.

1. Esterification or Transesterification:

In the PTA route, PTA reacts with MEG through an esterification reaction. In the DMT route, a transesterification reaction first takes place between DMT and MEG. At this stage, intermediate compounds and initial oligomers are formed.

2. Polycondensation:

The resulting oligomers then undergo polycondensation under controlled temperature and vacuum conditions. During this stage, the polymer chains gradually grow and the molecular weight of PET increases.

3. Formation of PET Polymer:

At the end of the process, PET polymer with the desired properties is produced. After leaving the reactor in its molten state, PET can be converted into different forms, such as pellets or chips, and then used to manufacture a wide range of products.

PET Grades and Forms

PET is available in different grades and forms depending on its end-use and processing requirements:

• Bottle Grade: Mainly used for beverage bottles, food containers, and other packaging applications.
• Film Grade: Used to manufacture PET films for packaging, electrical insulation, and industrial applications.
• Fiber Grade: Used in the production of polyester fibers for textiles, clothing, carpets, and industrial fabrics.
• Engineering/Industrial Grade: Designed for applications requiring higher mechanical, thermal, or dimensional performance, including electrical and industrial components.

Types of Polyethylene Terephthalate

PET can be classified into seven common grades and forms based on its properties, processing requirements, and end-use applications. These include PET Resin, PET Bottle Grade Resin, PET Film Grade, PET Fiber Grade, Sheet Grade PET, Engineering Grade PET, and Recycled PET (rPET).

1- PET Resin

PET Resin is a broad term used for polyethylene terephthalate in its resin form before it is processed into finished products. Depending on its molecular weight, intrinsic viscosity (IV), and other characteristics, PET resin can be manufactured for different applications such as bottles, films, fibers, sheets, and industrial products. The appropriate PET resin grade is selected based on the required processing method and the performance requirements of the final product.

2- PET Bottle Grade Resin

PET Bottle Grade Resin is specifically designed for the production of bottles and rigid packaging. It offers a combination of strength, clarity, chemical resistance, and good barrier properties, making it suitable for beverage bottles, food containers, and other packaging applications.

This grade is commonly processed through injection molding followed by stretch blow molding to produce lightweight and durable containers.

3- PET Film Grade

PET Film Grade is used to manufacture thin, flexible, and durable PET films. These films offer good mechanical strength, dimensional stability, transparency, and barrier properties. PET films are widely used in flexible packaging, electrical insulation, labels, printing, and various industrial applications where durability and dimensional stability are important.

4- PET Fiber Grade

PET Fiber Grade is designed primarily for the production of polyester fibers. It is widely used in the textile industry to manufacture clothing, home textiles, carpets, and industrial fabrics. PET-based fibers can be produced as staple fibers or continuous filaments and are valued for their strength, durability, dimensional stability, and resistance to wrinkling.

5- Recycled PET (rPET)

Recycled PET, commonly known as rPET, is produced by collecting, sorting, cleaning, and reprocessing PET products that have already been used. It can be manufactured from post-consumer or post-industrial PET waste. rPET is widely used in packaging, fibers, sheets, and other applications, helping reduce the demand for virgin PET and supporting a more circular approach to plastic production.

Virgin PET vs. Recycled PET

We have just talked about recycled PET, but you may be wondering: what is the difference between Virgin PET and Recycled PET?

Virgin PET is produced directly from its primary raw materials, such as PTA and MEG, without having been previously used or recycled. Recycled PET(rPET), on the other hand, is made by collecting and reprocessing PET products or waste that have already been used. While both materials can be used in applications such as packaging, fibers, and films, they may differ in properties, processing performance, appearance, and suitability for specific applications depending on the quality and recycling process.

In simple terms, Virgin PET is newly produced material, while Recycled PET is PET that has been recovered and processed for reuse.

6- Sheet Grade PET

Sheet Grade PET is produced for applications where PET is required in the form of rigid or semi-rigid sheets. It provides good clarity, strength, impact resistance, and dimensional stability.

PET sheets are commonly used in packaging, food trays, thermoformed products, protective covers, and other applications where transparency and rigidity are required.

7- Engineering Grade PET

Engineering Grade PET is developed for applications that require higher mechanical, thermal, and dimensional performance than conventional PET grades. It can be used in technical and industrial components where strength, stiffness, electrical properties, and dimensional stability are important. Depending on the formulation and application, engineering PET may be modified or reinforced to achieve specific performance requirements.

PET Glycol

Although PET Glycol is related to the PET family and is commonly associated with PET-based materials, it is important to understand that it is considered a separate chemical product rather than simply another PET grade. PET itself is a polymer, while glycol-based materials are used as chemical components or intermediates in the production and modification of polyester materials. Therefore, when discussing PET products in the chemical and petrochemical market, PET Glycol should be treated as a distinct product with its own properties, specifications, applications, and market considerations.

How to Choose the Right PET Resin Grade

Choosing the right PET resin grade depends primarily on the final application and processing method. Different grades are designed to meet specific requirements, such as bottle production, film manufacturing, fiber spinning, or industrial applications. Factors such as intrinsic viscosity (IV), mechanical strength, clarity, thermal performance, barrier properties, and processing conditions should be considered when selecting a grade.

It is also important to consider the required product specifications, production equipment, and end-use standards. For example, a PET resin intended for beverage bottles may require different properties from one used for fibers or films. Selecting the appropriate grade can help ensure consistent processing, product quality, and cost efficiency.

Major Polyethylene Terephthalate Producers Worldwide

Polyethylene Terephthalate is produced globally, with major production hubs in China, Southeast Asia, India, and the Americas. Leading producers include Indorama Ventures, Alpek, Far Eastern New Century (FENC), Zhejiang Hengyi Group, Reliance Industries, and major Chinese petrochemical companies, supplying PET grades for bottles, packaging, films, fibers, and industrial applications.

PET Manufacturing and Processing Methods

PET is manufactured and processed through several controlled stages, from polymer production to the formation of the final product. The main steps are:

1. Raw Material Preparation: The main raw materials, PTA(Purified Terephthalic Acid) and MEG(Monoethylene Glycol), are prepared and mixed in the required proportions. DMT may also be used as an alternative feedstock.
2. Polymerization: The raw materials undergo esterification or transesterification, followed by polycondensation. During polycondensation, the polymer chains grow and the PET reaches the required molecular weight and intrinsic viscosity.
3. Pellet or Chip Formation: The molten PET is cooled and cut into small pellets or chips. These PET resin forms are then supplied to manufacturers for further processing.
4. Drying: Before processing, PET resin must be properly dried because it is sensitive to moisture. Insufficient drying can cause hydrolysis and reduce the quality and mechanical properties of the final product.
5. Melting and Processing: The dried PET pellets are heated until they melt and are then processed using the appropriate manufacturing method, depending on the intended application.
6. Injection Molding: Molten PET is injected into a mold to create preforms, sheets, containers, and other shapes. Injection molding is particularly important in the production of PET bottle preforms.
7. Blow Molding: In bottle production, PET preforms are reheated and stretched inside a mold using air pressure to form the final bottle. Injection Stretch Blow Molding (ISBM) is widely used for beverage bottles.
8. Extrusion: Molten PET is forced through a die to produce continuous products such as films, sheets, and some industrial profiles.
9. Fiber Spinning: For textile applications, molten PET is extruded through small openings and drawn into continuous filaments or fibers. These fibers are then processed into textile and industrial materials.
10. Finishing and Quality Control: The final PET products undergo cooling, cutting, finishing, and quality-control checks to ensure they meet the required dimensions, strength, clarity, and application-specific specifications.

pet vs other polymer

The table below compares PET(Polyethylene Terephthalat) with several similar and widely used polymers, including PE(Polyethylene), PP(Polypropylene), PS(Polystyrene), and PVA(Polyvinyl Alcohol), based on their key properties, performance, and common applications.

disadvantages of PET

So far, we have mainly discussed the advantages of PET, but it also has some limitations. Polyethylene Terephthalate can be sensitive to high temperatures and moisture during processing, and it requires proper drying before molding to maintain its quality. It can also have lower resistance to certain chemicals and solvents compared with polymers such as PE and PP. In addition, although PET is highly recyclable, the recycling process requires proper collection, sorting, and processing infrastructure. These limitations should be considered when selecting PET for a specific application.

pet uses (pet application)

PET is a versatile polymer used across a wide range of industries. Its combination of strength, transparency, lightweight properties, chemical resistance, and recyclability makes it suitable for many applications:

• Beverage Bottles: Widely used for water, soft drinks, juices, and other beverages due to its lightweight, strength, and good barrier properties.
• Food Packaging: Used for food containers, trays, and packaging films because of its clarity, durability, and suitability for various packaging processes.
• Textile Fibers: PET is one of the most important raw materials for polyester fibers used in clothing, carpets, home textiles, and industrial fabrics.
• Packaging Films: PET films are used in flexible packaging, labels, printing, and other applications requiring high strength and dimensional stability.
• Industrial Films: Used in electrical insulation, protective films, and technical applications where mechanical and thermal performance are important.
• Sheets and Thermoformed Products: PET sheets are used to manufacture food trays, containers, protective covers, and other rigid packaging products.
• Automotive Applications: Certain PET grades are used in automotive components where strength, dimensional stability, and resistance to heat and chemicals are required.
• Electrical and Electronic Components: Engineering-grade PET can be used in electrical insulation, connectors, and other technical components due to its electrical and dimensional properties.
• Medical and Pharmaceutical Packaging: PET is used for certain bottles, containers, and packaging components where clarity, strength, and chemical resistance are important.

PET Price

The price of PET is influenced by both global raw material costs and market conditions. Since PET production depends mainly on feedstocks such as PTA and MEG, changes in their prices can directly affect PET resin costs. Regional supply and demand, production capacity, energy costs, freight rates, currency fluctuations, and changes in the packaging and textile industries can also influence market prices. As a result, PET prices may vary between grades, origins, quantities, and destinations.

What Affects PET Price?

• PTA and MEG Prices: Changes in the cost of PET’s primary raw materials directly influence production costs.
• Supply and Demand: Market demand from the beverage, packaging, textile, and industrial sectors can affect PET prices.
• Production Capacity: Plant shutdowns, maintenance, new capacity, or supply disruptions can impact availability and pricing.
• Energy Costs: Electricity, natural gas, and other energy costs contribute to overall PET manufacturing expenses.
• Freight and Logistics: Shipping costs, transportation distances, and destination can significantly affect the final delivered price.
• PET Grade: Bottle grade, film grade, fiber grade, and other PET grades may have different market prices.
• Order Quantity: Larger commercial volumes may receive different pricing compared with smaller quantities.
• Market Conditions: Currency movements, regional economic conditions, and changes in global petrochemical markets can influence PET prices.

Looking for a reliable PET supplier? Nowfel supplies PET grades to customers in more than 60 countries. Contact our sales team with your required grade, quantity, and destination to receive a current quotation.

Why Choose Us as Your PET Supplier?

Choosing a PET supplier involves more than comparing prices. Product grade, technical specifications, quality, documentation, and international logistics all play an important role in a successful purchase. Nowfel FZC supports customers throughout the sourcing and export process, helping them select the appropriate PET grade and coordinate the requirements of international shipments.

1. Wide Range of PET Grades: Supply of different PET grades for bottles, films, fibers, sheets, and other applications.
2. Technical Specifications: Assistance with product specifications and selecting the appropriate grade based on the intended application.
3. Quality Control: Products supplied according to agreed technical specifications and quality requirements.
4. Export Documentation: Support with the documentation required for international PET shipments.
5. International Logistics: Coordination of shipping and delivery requirements for different countries and destinations.
6. B2B Support: Assistance with quotations, orders, documentation, and shipment coordination throughout the purchasing process.
7. Reliable Communication: Clear and consistent communication from initial inquiry through order fulfillment and delivery.

For more information or to purchase PET, feel free to contact us by email. Our sales and support team will get back to you as soon as possible and assist you with your requirements.