PLA and PBAT are the two names you'll see most often on compostable packaging. They're not rivals. They're teammates with different strengths, and the best compostable films often use both. Here's how they compare, and what it means when you're choosing a product.
The quick comparison
| PLA | PBAT | |
|---|---|---|
| Full name | Polylactic acid | Poly(butylene adipate-co-terephthalate) |
| Made from | Plant sugars (e.g. sugarcane, corn) | Fossil-based ingredients |
| Feel | Stiff, strong, clear | Soft, stretchy, tear-resistant |
| Typical uses | Cups, trays, films (often blended) | Flexible bags and films (often blended) |
| End of life | Breaks down to CO2, water and biomass in compost | Breaks down to CO2, water and biomass in compost |
| Home compostable? | Depends on the finished product's certification | Depends on the finished product's certification |
What is PLA?
PLA is a bioplastic made by fermenting plant sugars into lactic acid, then linking that acid into long chains. Because it comes from plants, it's renewable. It's strong and clear, but on its own it's fairly stiff and can snap rather than stretch. Read more in What is PLA?
What is PBAT?
PBAT is a compostable copolyester made from fossil-based ingredients. Its strength is flexibility: it stretches, seals and resists tearing. It doesn't have PLA's renewable origin, but it's designed to biodegrade in compost, unlike conventional plastic. More in What is PBAT?
Why blend them?
Put the two together and you get the best of both: PLA's strength and plant-based origin, plus PBAT's stretch and toughness. Blend ratios vary depending on the job. More PLA gives you a crisper, stiffer film. More PBAT gives you a softer, stretchier one.
Here's how that plays out across the ZERO range:
- ZERO Cling Wrap is mainly PLA made from sugarcane (bagasse), with about 20% PBAT for stretch. Mostly plant-based, with just enough flexibility to cling.
- ZERO Resealable Food Storage Bags are made from PBAT, corn starch and calcium carbonate, with no PLA. A bag needs to flex, seal and survive a packed lunchbox, so PBAT does the heavy lifting here.
Both are certified home compostable.
Do PLA and PBAT need industrial composting?
Not necessarily. This is one of the most common misunderstandings in the category.
Both materials break down the same basic way. Water breaks their chains into shorter pieces, then microbes digest those pieces into carbon dioxide, water and biomass. How fast that happens depends on temperature, moisture and microbes, and also on the product itself: its thickness, its formulation and what it's blended with.
That's why certification tests the finished product. In Australia:
- AS 4736 certifies a product as industrially compostable.
- AS 5810 certifies a product as home compostable, tested at the lower temperatures of a backyard bin.
Some PLA and PBAT products, like thick rigid items, are only certified for industrial composting. Others are thin and formulated to pass home composting tests. ZERO Cling Wrap is certified home compostable (DIN CERTCO; TÜV Austria OK compost HOME), and ZERO's resealable bags are certified home compostable (TÜV Austria OK compost HOME). For more, read home compostable vs industrial.
What about microplastics?
Like many materials, PLA and PBAT can break into smaller fragments as they start to degrade. The difference from conventional plastic is what happens next. In compost, those fragments keep breaking down until they're carbon dioxide, water and biomass, so they don't persist the way conventional polymers do. We go deeper on this in Does PLA create microplastics?
The practical takeaway: get certified compostable products into compost, not litter or the ocean.
Which should you choose?
As a shopper, you don't really need to choose between PLA and PBAT. Choose by job, and check the label.
- Need a wrap that clings? A PLA-based film with a little PBAT, like ZERO Cling Wrap (from $6.99).
- Need a bag that seals and flexes? A PBAT-based bag, like ZERO Resealable Food Storage Bags (from $4.99).
- Either way: look for a home compostable certification if you want to put it in your own compost.
Four label checks before you buy
- Is there a certification mark? A named scheme beats a vague "eco" claim.
- Does it say home or industrial? They're not the same thing.
- Is it tested for food contact if it's going near your food?
- Are the disposal instructions clear? You shouldn't have to guess.
FAQ
Is PLA better than PBAT?
Neither is "better". PLA is plant-based and strong; PBAT is flexible and tough. Blends use both.
Can I put PLA or PBAT products in my home compost?
If the product is certified home compostable, yes. All of ZERO's cling wrap and bags are.
Can I recycle PLA or PBAT?
Not in kerbside recycling or soft plastics collection. Compost certified products according to their label.
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