Bio-Polyesters
When You Hear "Polyester," Do You Think "Synthetic & Non-Biodegradable"? Think Again.
When we hear the word "polyester," the first thought that usually comes to mind is "synthetic plastic." That’s not wrong but does that mean all polyesters are non-biodegradable?
Let’s explore this in more detail.
The Conventional Polyester Story
Traditionally, polyester is made from fossil fuel–based chemicals, with crude oil as the primary raw material. Commercial polyester (mainly PET or polyethylene terephthalate) is derived from:
Ethylene and ethylene glycol
Para-xylene, which is oxidized to produce terephthalic acid (TPA)
These components together form PET, a non-biodegradable plastic that often ends up in landfills or oceans, eventually breaking down into harmful microplastics.
But Not All Polyesters Are the Same
Few people realize that not all polyesters are non-biodegradable. There are biodegradable polyesters that offer environmentally friendly alternatives to conventional plastics. Here are two notable examples:
1. Polybutylene Succinate (PBS)
PBS is a biodegradable aliphatic polyester with mechanical properties similar to polypropylene. It is derived from succinic acid and 1,4-butanediol, both of which can be bio-based.
Biodegradable into water and CO₂ by natural microbial action
Heat-resistant and suitable for film, packaging, and molded products
A strong candidate for replacing fossil-based plastics in rigid and flexible applications
2. Polybutylene Adipate Terephthalate (PBAT)
PBAT is a biodegradable co-polyester made from adipic acid, 1,4-butanediol, and terephthalic acid. Despite containing aromatic components, it still breaks down in composting environments.
Compostable and flexible, making it ideal for films and bags
Has mechanical properties similar to LDPE (low-density polyethylene)
Often used in blends with PLA or starch to improve processability and biodegradability
What About PLA?
PLA (Polylactic Acid) has become a buzzword in sustainable packaging. It's bio-based and biodegradable, but it comes with technical limitations:
Brittle nature
Lower thermal resistance
Limited flexibility
In applications where PLA cannot perform, PBS and PBAT can be excellent alternatives.
Conclusion: Rethink “Polyester”
So, the next time you hear the word "polyester," remember:
Not all polyesters are the same. Some are designed to protect the planet, not pollute it.
If you’re working toward sustainable materials in packaging, textiles, or consumer products, PBS and PBAT are worth considering just as much as PLA.
Let’s drive awareness and innovation by embracing the full spectrum of biodegradable polyesters.