As two popular non-crystalline copolyester materials, PETG and PCTG are often compared in terms of their chemical composition and physical properties. Although they share some similarities, there are also significant differences between the two. In this blog post, we will dive deeper into the characteristics of PETG and PCTG, and discuss their respective applications.
Chemical Composition
PETG, or polyethylene terephthalate glycol, is composed of terephthalic acid (PTA), ethylene glycol (EG) and 1,4-cyclohexanedimethanol (CHDM). The proportion of CHDM in PETG does not exceed 50%. On the other hand, PCTG, or glycol-modified PET, has a higher CHDM content, making up more than 50% of its composition. The use of CHDM in both materials results in a reduction of crystallinity, making them more transparent and resistant to stress cracking.
Physical Properties
Both PETG and PCTG are highly transparent and provide a glossy surface finish. However, due to the higher CHDM content in PCTG, there is a possibility that the final product may not exhibit the same level of gloss as PETG. In terms of chemical resistance, both materials offer a wide range of chemical resistance, with PCTG exhibiting better performance in high-temperature applications.
Applications
PETG is often used in the production of high-end cosmetics and transparent packaging containers due to its excellent formability and processing properties. It can be easily molded into various shapes and sizes, making it a versatile material for packaging and display purposes. PCTG, on the other hand, is primarily used in food containers, refrigerator storage compartments, and other products that require exposure to low-temperature environments. PCTG offers superior toughness and durability, making it an ideal material for applications that require long-term performance in harsh conditions.
Copolyester PETG/PCTG products are primarily produced by American companies like Eastman and South Korean company SK Chemical. They are high-performance polymer materials situated at the top of the polymer material pyramid. Dawn Helf's proprietary patent technology for copolyester materials has filled a technological gap in China. Dawn Helf's copolyester PETG/PCTG materials have received certifications such as FDA and food contact safety. As a new type of resin material, they have unique properties and price advantages in application areas where they replace materials like PC and PMMA. Understanding their chemical composition and physical properties is important in choosing the right material for the intended use. Whether you need a material that is highly transparent, resistant to chemicals, or can withstand low temperatures, there is a copolyester material that can meet your specific requirements.
If you have interest on PETG or PCTG, please contact us or inquire online!