PET to PETG Conversion

Basics

• Pet (Plastic) is a common plastic, mainly found in disposable water bottles
• HOWEVER it is very moisture sensitive, and doesn't lend itself to fdm 3d printing
• PETG however is reletively in between PLA and ABS and is a great fdm plastic
• As of now this page is for research on how to convert pet to petg, and see if it can be done economically
• Calling all chemists!

Methods

• Technically speaking PETG is a Copolymer of PET and Cyclohexanedimethanol(CHDM)
• From the Filaments article:
  • The first step in PETG synthesis is esterification of TPA, EG and CHDM at around 230 in a nitrogen atmosphere, this is when the first polycondensation reaction occurs in the presence of a metal catalyst, usually cobalt. The second polycondensation step is carried out at high temperature (usually around 280) under high vacuum conditions
• Seems like it will be makerspace and up level due to the need for nitrogen gas, and a vacuum

Internal Links

• Pet (Plastic)
• PETG

External Links

• The Wikipedia Page on PET Plastic
• The Wikipedia Page on PETG
• A Hackaday Article on How this is done Industrially
• An Webpage from the site "Filaments.Directory" on PETG
• A Patent on a Process for This depolerizes PET in chamber with catalyst, then uses the same chamber to re-polymerize into PETG?